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1
Chaudhry, Abdul Shakoor. "Nutritional improvements of cereal straws". Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279301.
Testo completo
2
Clarke, Emily Jane. "Nutritional value of soya beans for broiler chicks". Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366471.
Testo completo
3
Rehman, Salim-Ur. "Factors influencing quality and nutritional value in chapaties". Thesis, University of Strathclyde, 1994. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=23309.
Testo completoAbstract (sommario):
Chapati, an unleavened flat bread, is a staple in the diet in Pakistan. Wheat in the form of chapati can contribute as much as 90% of the total dietary energy intake to the rural population and generally provides more than half dietary energy and protein. Such a heavy dependence on this cereal food has led to protein malnutrition due to wheat proteins being deficient in lysine, an essential amino acid. The aim of this study was to produce savoury chapati with enhanced nutritional value. Attitudes to a variety of savoury flavours were determined in consumers of Pakistan and in immigrants to Glasgow. Chicken and meaty were most and cheesy least preferred. Amongst chapati quality characters, nutritional value was rated highest followed by flavour. These studies suggested that consumers favoured a product with appropriate flavour, a soft texture and of high nutritional value. Typically chapaties are prepared with wholemeal flours with medium rheological optima. Doughs of British wheat varieties Fresco and Galahad (33+67) and Mercia and Galahad (50+50) had moderate stickiness, high sheeting ability, and were low in shrinkage after sheeting. Such suitable mixtures yielded flours suitable for chapati production. Wheat protein profiles were determined by electrophoresis and relationships between proteins and rheological properties determined with partial least squares regression (PLS2). Dough development time was positively correlated with aggregated values of high molecular weight (HMW) and low molecular weight (LMW) glutenins, ratio of polymeric to monomeric and LMW glutenins, and negatively correlated with the total of gliadin, globulin and albumin fractions. Dough stability showed negative and tolerance index positive correlations with gliadin. Resistance to extension was associated with dough stability and inversely with gliadin content. Such studies reveal that glutenin contributes strength and gliadin imparts weakness to flour. Response surface methodology, used to optimise chapa ties , revealed that a successful savoury product could be produced by incorporating 1.5 to 2.0 % yeast extract without any deleterious effect on dough physical characteristics. Yeast extract enhanced the concentrations of protein from 13.1 % to 14.4 % in chapati. In addition to enhanced nutritional value, yeast extract imparted a desirable savoury flavour to chapati.
4
Matos, Bárbara Cartagena da Silva. "Do sea otters according to prey's nutritional value?" Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17176.
Testo completoAbstract (sommario):
Mestrado em Ecologia AplicadaA Teoria do Forrageio Ótimo propõe que o estímulo nutricional na escolha de presas e busca de alimento em carnívoros é o ganho energético. Em contraste, pesquisas recentes sugerem que os carnívoros selecionam presas que fornecem uma dieta com um equilíbrio específico de macronutrientes (gordura, proteína, hidratos de carbono), ao invés do maior conteúdo energético. Para este efeito, as escolhas de presas de lontras-marinhas (Enhydra lutris) que habitam Sitka Sound no sudeste do Alasca, foram estudadas durante os meses de maio a agosto de 2016. Os objetivos desta pesquisa foram: 1) descrever a dieta das lontras-marinhas em Sitka Sound; 2) descrever o valor nutricional das suas presas; 3) comparar diferenças na escolha de presas de acordo com o sexo; e 4) avaliar e comparar o valor nutricional das presas com as escolhas das lontras-marinhas. Os dados de observação foram coletados oportunisticamente, através de uma plataforma de oportunidade. As presas de lontras-marinhas foram capturadas em áreas arbitrárias de Sitka Sound, e analisadas quanto à sua percentagem em lípidos (teor de gordura) e calorias (densidade de energia). O consumo de presas foi significativamente diferente: as amêijoas foram as presas mais consumidas (68,6%), seguidos pelos ouriços-do-mar (14,3%), vieiras (5,7%), pepinos-do-mar (5,7%), caranguejos (2,9%) e estrelas-do-mar (2,9%). Além disso, os resultados revelaram uma significativa diversidade no conteúdo de gordura e densidade energética entre presas de lontra-marinha. O abalone registou maior teor de densidade energética, seguido pelas vieiras, enquanto que os ouriços-do-mar registaram maior teor em lípidos. A escolha de presas e a ingestão de nutrientes não diferiram significativamente entre machos e fêmeas, no entanto, os machos de lontras-marinhas consumiram mais moluscos do que as fêmeas, enquanto que as fêmeas consumiram mais ouriços-do-mar do que os machos. O trabalho sobre nutrição em carnívoros é preliminar, e estes resultados fornecem um ponto de partida para futuras pesquisas. As respostas a estas questões não só terão implicações significativas na gestão das populações de predadores e das comunidades ecológicas de que fazem parte, mas também acrescentarão informações importantes sobre a biologia de predadores que até agora foram negligenciadas. Além disso, os conflitos nas comunidades sobre os impactos que as lontras-marinhas têm na pesca comercial no sudeste do Alasca, não podem ser ignorados. Compreender as escolhas de presas de lontras-marinhas pode fornecer previsões de como a pesca pode ser afetada, de acordo com o crescimento da população de lontras nesta área, a fim de ajudar políticos, membros da comunidade e pescadores comerciais, a responder em conformidade.
Foraging theory proposes that the nutritional driver of prey choice and foraging in carnivores is energy gain. In contrast, recent research suggests that carnivores select prey that provides a diet with a specific balance of macronutrients (fat, protein, carbohydrates), rather than the highest energy content. To this effect, the prey choices of sea otters (Enhydra lutris) inhabiting Sitka Sound, in southeast Alaska, were studied during the months of May-August of 2016. The goals of this research were to 1) describe sea otter’s diet in Sitka Sound; 2) describe the nutritional value of sea otters’ prey items; 3) compare differences in prey choice according to sex; and 4) evaluate and compare prey’s nutritional value with sea otter’s prey choices. Foraging observational data were collected opportunistically on a boat-based platform of opportunity. Sea otter’s main prey were captured in arbitrary areas of Sitka Sound, and analyzed for percentage in lipids (fat content), and calories (energy density). Prey consumption was significantly different: clams were the most frequently consumed prey (68,6%), followed by sea urchins (14,3%), scallops (5,7%), sea cucumbers (5,7%), crabs (2,9%) and sea stars (2,9%). Also, the results revealed a significant diversity in content of fat and energy density between sea otter prey specimens. Abalone ranked first on content of energy density, followed by scallops, while sea urchins recorded the highest lipid content. Prey choice and nutrient intake were not significant different between male and female sea otters, nevertheless, males consumed more clams than females, while females consumed more sea urchins than males. The work on carnivore nutrition is preliminary, and these results provide a starting point for future work. Answers to such questions not only will have significant implications for managing predator populations and the ecological communities of which they are a part, but will also add important information on predator biology that has been neglected so far. Moreover, communities’ conflicts over the impacts sea otters are having on commercial shellfisheries in southeast Alaska cannot be overlooked. Understanding sea otter’s prey choices may provide information and predictions of how fisheries may be affected as the sea otter population grows in this area, in order to help decision makers, policy makers, community members, and commercial fishermen respond accordingly.
5
Abdel-Muttalab, Salah Ahmed. "Nutritional value of rapeseed and faba bean for poultry". Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283076.
Testo completo
6
D'Souza, Frances M. L. "The nutritional value of microalgae to penaeid prawn larvae". Thesis, Queensland University of Technology, 1997. https://eprints.qut.edu.au/36935/1/36935_Digitised%20Thesis.pdf.
Testo completoAbstract (sommario):
This is the first study to investigate the nutritional requirements of the penaeid prawn protozoeal phase (the first feeding stage of the prawn life cycle) using micro algae to provide different nutritional conditions.
The work was a simultaneous examination of the biochemical
composition of the larvae and their microalgal diets. In addition, the influence of naupliar composition on later larval stages was studied. The biochemical parameters measured were total protein, lipid and carbohydrate (i.e. gross biochemical composition) and total lipid was further resolved into individual fatty acids.
The nutritional requirements of penaeid prawn larvae were assessed by measuring the survival, development (metamorphosis) and growth (in terms of dry weight) of larvae in response to various algal diets. In
this way differences in survival, development and growth could be related to biochemical differences in the algal diets and associated larval body composition.
The changes in biochemical composition of *Penaeus japonicus* and *P. monodon* larvae during metamorphosis from nauplii to protozoea 1 (PZl) and the time course of these changes during starvation and feeding for the ~42 h period that the PZl stage lasts, were examined. The larvae utilised lipid as a major energy source during metamorphosis. The fatty acid fraction of the lipid in nauplii was high
(60 to 80%) compared with protozoeae (30 to 60%) and provided a large proportion of the energy required for metamorphosis. Of the total fatty acids, the monounsaturated (MUFAs) and saturated fatty
acids contributed most of this energy. During starvation the MUFAs and polyunsaturated fatty acids (PUPAs) were metabolised while the highly unsaturated fatty acids (HUFAs) were conserved, presumably because of their role as structural components in cell membranes. The
PUFA linoleic acid (18:2n-6) appeared to have a role as a component of cell membranes when in short supply, but it accumulated as an energy reserve when in excess in the diet. Linolenic acid (18:3n-3) was actively metabolised to other membrane fatty acids or used for energy.
The effect of altering the biochemical composition of the microalga
*Tetraselmis suecica* on *P. semisulcatus* larvae was studied by reducing the nitrate concentration from -1760 μ*M* to 176 μ*M* in the culture media. Carbohydrate increased three fold in the low nitrate algae, and protein and lipid were reduced slightly compared to the control. The
low protein:energy ratio (0.1 to 0.2) of the low nitrate diets resulted in a delay in the development of the larvae compared to that of the animals fed the control diet (ratio 0.3 to 0.4). Survival was not affected by the algal diets.
Four species of algae (*Tetraselmis suecica*, *Chaetoceros muelleri*, Tahitian *Isochrysis* sp. (T-iso) and *Dunaliella tertiolecta*) differing predominantly in their fatty acid composition were fed to *P. japonicas* larvae as single species diets. The two best diets (in terms of growth
and survival of the prawn larvae) were subsequently fed in combination to *P. semisulcatus* and *P. monodon* larvae to assess their nutritional value as part of a mixed diet. The survival and development to mysis 1 (M1), i.e. performance, of the larvae was affected by the algal diets
such that the diets could be ranked: *C. muelleri* > *T. suecica* > *Isochrysis* sp. (T-iso) > *D. tertiolecta*. The fatty acid profiles of the algae, particularly those of arachidonic acid (20:4n-6) and eicosapentaenoic acid (20:5n-6), were related to those of the larvae and
their performance. The presence of both of these fatty acids in the algal diet was necessary to produce high performance whereas docosahexaenoic acid (22:6n-3) was not. The low requirements for the PUPAs 18:2n-6 and 18:3n-3 were modulated by the presence of HUFAs such as 20:4n-6, 20:5n-6 and 22:6n-3. Therefore when these HUFAs were present in the diet, less 18:2n-6 and 18:3n-3 were required. However high proportions of 18:2n-6 and 18:3n-3 alone, did not
replace the requirements for 20:4n-6, 20:5n-6 and 22:6n-3.
Understanding the nutritional requirements of penaeid prawn larvae will lead to the production of a cost effective and optimum diet for use in hatcheries. In addition, this research will contribute to the production of a purified artificial diet for penaeid prawn larvae which can be used to examine the requirements for other nutrients.
7
Lewu, Muinat Nike. "Studies on the nutritional value of seven accessions of cocoyam growing in South Africa". Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/d1001054.
Testo completoAbstract (sommario):
Cocoyam [Colocasia esculenta (L.) Schott] is widely cultivated as a staple food in the tropical and subtropical regions of the world. The crop, however, remains unpopular and not well known outside KwaZulu-Natal Province of South Africa where it is cultivated mainly for subsistence. The aims of the study were to collect local landraces (accessions) of the crop from where it is found growing within the country for various studies and also to document its nutritional values as well as the safety/toxicity of the crop. The study was carried out using various methods. These included a comparative assessment of the proximate, mineral and antinutrient compositions of cooked and uncooked tubers of a typical commercially available cocoyam and potato found in South African markets. These investigations were repeated for the tubers and leaves of available landraces (seven accessions) of C. esculenta found growing in the farmers’ fields in KwaZulu-Natal Province. Also, an in vivo toxicological study on cooked accessions of the local landraces was conducted to determine possible toxicity effects after consumption using albino rats as a model. The results revealed that commercially available cocoyam and potato tubers have very close nutritional components. Analysis of the proximate composition of seven accessions (UFCe1- UFCe7) of cooked and uncooked tubers of cocoyam indicated that UFCe7 was better in ash, crude protein, crude fibre and crude lipid contents but with higher moisture which could make it more vulnerable to microbial attack. No tubers of the seven accessions appeared to be ii outstandingly better than the others based on their mineral compositions. However, in terms of antinutritional factors, UFCe1, UFCe3 and UFCe7 had the least amounts of oxalate, tannins and phytate in their cooked states. It was discovered however, that the leaves of the accessions of this vegetable contain substantial amount of minerals, and therefore, can contribute significantly to the nutrient requirements of humans and could be recommended as a cheap source of nutrients in South Africa. None of the accessions was outstandingly better than the others in terms of their mineral contents and anti-nutritional factors. Moreover, the current study has shown that boiling the leaves of cocoyam prior to consumption is an effective way of reducing the antinutrient contents of the leaves of the plant thereby making it safe for consumption. The findings also revealed that cooking C. esculenta leaves may increase the levels of protein, fibre and lipid contents while cooking may also decrease the mineral, carbohydrate and caloric contents of the leaves of the accessions. The leafy vegetable may, therefore, be recommended as a cheap source of plant protein. Cooking improved the nutritive value as a result of the reduction in antinutrient levels, thereby improving the food quality in all the tuber and leaf samples used for this study. At the same time, cooked samples also suffered loss of some nutrients with respect to the proximate and mineral compositions. However, supplementation from other food sources that are rich in these nutrients is necessary when these crops are cooked for consumption. Any of the cocoyam accessions may be recommended for consumption for improved protein and mineral nutrients while tubers of accession UFCe7 have also shown good promise in terms of protein and fibre content availability. The results of the in vivo study, using the liver and kidney functional endpoints of weanling albino rats (Rattus norvegicus) maintained on different accessions of cooked cocoyam-based iii diets (UFCe1-UFCe7) for 28 days, revealed that all the accessions produced selective alterations on the hepatorenal indices of weanling rats. The highest alterations were produced by UFCe4 while the least was from UFCe2. These alterations may have consequential effects on the normal functioning of the liver and kidney of the animals. The UFCe2 exhibited the least toxicity risk among the accessions of C. esculenta growing in KwaZulu-Natal Province of South Africa.
8
Qiao, Yanrui. "Routine techniques for monitoring the nutritional value of animal meals". NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20011030-112347.
Testo completoAbstract (sommario):
Feed mills demand routine techniques to analyze digestible amino acids in highly variable animal meals. As routine tools, infrared spectroscopic predictions of digestible amino acids require reference samples assayed in vivo. Lack of reference samples resulting from costly and time-consuming in vivo assays has limited infrared spectroscopic applications. To remove this limitation, an in vitro assay mimicking in vivo digestion in swine was sought as a replacement to build the reference database.
Pepsin and pancreatic proteases used in the in vitro assays produce autolysates that are assayed as digestible amino acids. To correct this contamination and define incubation time for efficient use of the proteases, the autolysis of these proteases was studied. Correction of enzyme contamination with enzyme blank incubations and incubation time of 24 hours for pepsin and 96 hours for pancreatic proteases were proposed (Chapter III and IV).
In vitro digestion focused on maximal hydrolysis of peptide bonds with minimal enzyme usages for restriction of enzyme contamination. The minimal enzyme usage was determined to be 6.5% (enzyme to substrate ratio) (Chapter V).
Study on absorption of peptides in swine revealed that all soluble in vitro peptides could be estimated as digestible in vivo. Average in vitro digestibility coefficients were comparable to in vivo for a number of amino acids but mismatch occurred for individual samples. In vivo digestible amino acids, though, could be predicted with in vitro digestible amino acids. For example, lysine was predicted with an error of 0.27% (Chapter VI).
Total and digestible amino acids were predicted with near infrared reflectance spectroscopy (NIRS) and mid infrared Fourier transform infrared spectroscopy (FTIR) but not with Raman spectroscopy. Infrared spectroscopic prediction errors for digestible lysine were 0.27% for near infrared spectroscopy and 0.26% for mid infrared spectroscopy. Total amino acids seemed better predicted than digestible amino acids by infrared spectroscopy (Chapter VII).
The study showed that as routine techniques, infrared spectroscopy could potentially replace both in vivo and wet chemical analyses of amino acids.
9
Ряшко, Галина Михайлівна, e Вікторія Миколаївна Шелудько. "DESIGNING OF BAKING AREA SPECIALIZING ON HIGH NUTRITIONAL VALUE PRODUCTS". Thesis, Прага, 2021. http://dspace.puet.edu.ua/handle/123456789/10725.
Testo completo
10
Ряшко, Галина Михайлівна, e Вікторія Миколаївна Шелудько. "Designing of baking area specializing on high nutritional value products". Thesis, Oktan Print, 2021. http://dspace.puet.edu.ua/handle/123456789/11027.
Testo completo
11
Mundie, Benjamin Scott. "Nutritional Value of Warm- and Cool-Season Grasses for Ruminants". Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/42804.
Testo completoAbstract (sommario):
A metabolism trial was conducted to compare the nutritional value of: 1)â Quickstandâ bermudagrass [Cynodon dactylon (L.) Pers.], 2)caucasian bluestem [Bothriochloa caucasia (Trin.) C.E. Hubb], 3)tall fescue (Festuca arundinacea Schreb.), and 4)orchardgrass (Dactylis glomerata L.). The warm-season grasses (bermudagrass and bluestem) were higher (P < .01) in fiber components than the cool-season grasses (tall fescue and orchardgrass). Bluestem was lower (P < .001) in CP, hemicellulose, and ash, and higher in NDF (P < .001), ADF (P < .001), cellulose (P < .001), and lignin (P < .01) than bermudagrass. The warm-season grasses were lower in the apparent digestibility of DM (P < .001), NDF (P < .01), ADF (P < .05), cellulose (P < .05), and hemicellulose (P < .01) than cool-season grasses. Apparent digestibility of NDF (P < .001), ADF (P < .001), cellulose (P < .01), and hemicellulose (P < .01) was higher for bluestem than bermudagrass. Fescue was higher (P < .001) in apparent digestibility of DM and CP and lower (P < .01) in apparent digestibility of NDF, ADF, cellulose, and hemicellulose than orchardgrass. Lambs fed bluestem had lower (P < .05) N retention than those fed bermudagrass, when expressed as g/d. Lambs fed fescue had higher (P < .001) N retention, than those fed orchardgrass. When expressed as a percent of intake or absorption, N retention values were similar among treatments. The results of this study suggest that cool-season grasses are of higher nutritional value than warm-season grasses.Master of Science
12
Issa, Salissou. "Nutritional value of sorghum for poultry feed in West Africa". Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/2322.
Testo completo
13
Adebiyi, Adekunle Olalekan. "The nutritional value for poultry and pigs of biofuel co-products". Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5432/.
Testo completoAbstract (sommario):
A total of five studies were conducted to determine the nutritional value of co-products of bioethanol production for poultry and pigs. The objective in the first study was to evaluate the relationship between the chemical components of maize- and wheat distillers dried grains with solubles (DDGS) as well as develop prediction equations for indispensable amino acids (IAA), total indispensable amino acid (TIAA) and total amino acid (TAA) contents using nutrient composition data available in literature. The relationship between the chemical constituents of maize- and wheat-DDGS and associated probability values were determined by correlation analysis. Prediction models for determining the IAA, TIAA and TAA contents of maize- and wheat-DDGS from their crude protein (CP) and amino acids (AA) contents were developed using step-wise multiple regression analyses. Maximum improvement in adjusted r2 (adj r2) and reduction in Mallows Cp were the model selection criteria. The chemical composition of maize- and wheat-DDGS varied among sources with coefficient of variation (CV) ranging from 8.5% to 53.5% for total P and Ca respectively in maize-DDGS and 10.5% to 36.1% for CP and acid detergent fibre (ADF) in wheat-DDGS respectively. Of the IAA, Lys, Met and Trp were most variable in maize-DDGS with CV of 13.1%, 12.0%, 10.3%, respectively, whereas Lys, Phe and Met were the most variable IAA in wheat-DDGS with CV of 20.2%, 17.3%, and 16.9%, respectively. For maize-DDGS, there were positive correlations (P < 0.05) between CP and CF, NDF, Ca, ash (r ranged from 0.45 and 0.61). Adjusted r2 ranged from 0.57 to 0.99 in the best models for predicting the IAA in maize- and wheat-DDGS from CP and AA. Except for Trp and Lys, the IAA contents of maize- and wheat-DDGS can be predicted from their CP content alone. The best models for predicting TIAA and TAA in maize-DDGS included Arg, His and Leu (adj r2= 0.98) and His, Leu and Trp (adj r2= 0.90) respectively, the regression equations being TIAA (% DM) = 0.77 + 1.36 (Arg) + 3.87 (His) + 1.99 (Val) and TAA = -3.03 + 14.1 (His) + 3.79 (Leu) + 23.4 (Trp) respectively. For wheat-DDGS, the best three variables for predicting TIAA were Arg, Leu and Val (adj r2=0.99), the regression equation being TIAA (% DM) = -0.07 + 1.11 (Arg) + 0.99 (Leu) + 5.02 (Val). Predicted values were close to actual values in the prediction models for IAA, TIAA and TAA. It was concluded that the IAA, TIAA and TAA contents of both maize- and wheat-DDGS can be predicted from their CP contents with high accuracy. In the second study, the nutritional value of wheat-DDGS without- or with exogenous enzymes for broiler was determined using three experiments. The N-corrected- and apparent metabolisable energy contents (AMEn and AME, respectively) without- or with added admixture of xylanase, amylase and protease (XAP) was determined in experiment 1, true P digestibility without- or with supplemental phytase was determined in experiment 2, whereas the apparent- or standardised ileal digestibility (AID and SID, respectively) of AA without- or with added protease was determined in experiment 3. Birds were fed a nutrient adequate pre-experimental diet from d 1 to 14 post-hatch followed by the dietary treatments from d 14 to 21 in experiment 1 and 2, or from d 25 to 28 in experiment 3, respectively. Each of the 3 experiments was arranged as a randomised complete block design consisting of 7 replicate pens and 3 birds per pen. Six dietary treatments consisting of 3 levels of wheat-DDGS (0, 300 or 600 g/kg of diet) and 2 levels of XAP (0 or 0.25 g/kg) were used in experiment 1. Six diets consisting of 3 levels of wheat-DDGS (200, 400 or 600 g/kg of diet) and 2 levels of phytase (0 or 1000 FTU/kg) were used in experiment 2, whereas four treatments consisting of a nitrogen-free diet (NFD) and an assay diet, both diets without- or with supplemental protease were used in experiment 3. In experiment 1, increasing the level of wheat-DDGS in the basal diet decreased linearly (P < 0.001) dry matter (DM) and energy retention, AME and AMEn. Supplemental XAP tended to improve both the dietary AME (P = 0.059) and AMEn (P = 0.085) values of the diet. The AME value of wheat-DDGS without- or with supplemental XAP was determined to be 15.0 or 15.5 MJ/kg, respectively. Corresponding values for AMEn were 14.0 and 14.5 MJ/kg, respectively. Supplemental XAP did not improve the energy value of wheat-DDGS for broilers. In experiment 2, increasing the level of wheat-DDGS in the diet decreased linearly (P < 0.05) ileal DM digestibility, DM retention and apparent P retention but there was no difference in apparent ileal P digestibility. Except for Fe and Zn at the ileal, and Mn and Zn at the total tract level, increasing the level of wheat-DDGS in the diet increased linearly (P < 0.05) the flow of all other minerals. Flow of minerals at the ileal and total tract level were not different with phytase supplementation. True ileal P digestibility in the wheat-DDGS for broilers was 93.6 or 96% without- or with added phytase, respectively. Corresponding values at the total tract level were 92.4 and 93.5%, respectively. Phytase addition did not improve P utilisation at the ileal or total tract level. In experiment 3, AID ranged from 33% (Asp) to 75% (Pro) without added protease whereas the range was 31% (Asp) to 82% (Pro) with protease supplementation. The AID of Lys was nil regardless of protease supplementation. Supplemental protease improved (P < 0.05) the AID of Arg and Pro and tended to improve (P < 0.10) the AID of Met. Without protease supplementation, SID ranged from 43% (Asp) to 84% (Pro) whereas the range was from 54% (Asp) to 93% (Pro) with added protease. Supplemental protease improved (P < 0.05) the SID of Arg, Leu, Phe, Met, Val and Pro by 21, 14, 13, 26, 13 and 10 percentage points, respectively. It was concluded that wheat-DDGS is a good dietary source of metabolisable energy and P for broilers. The ileal AA digestibility of wheat-DDGS for broilers is quite variable and generally low. Further, the ileal digestibility of some AA in the wheat-DDGS improved with protease supplementation. Using three experiments the third study determined the metabolisable energy content, true P digestibility and retention and AIAAD and SIAAD of wheat-DDGS for turkey. The AMEn and AME content of wheat-DDGS without- or with XAP was determined in experiment 1, the true P digestibility and retention without- or with supplemental phytase was determined in experiment 2, whereas the AIAAD and SIAAD of wheat-DDGS without- or with a protease were determined in experiment 3. Experiment 1 and 2 lasted for 21 days whereas experiment 3 lasted for 28 days. Experimental diets were fed for 7, 5 or 3 d in experiment 1, 2 or 3, respectively. Each of the 3 experiments was arranged as a randomised complete block design consisting of 7 replicate pens and 3 birds per pen. Six dietary treatments consisting of 3 levels of wheat-DDGS (0, 300 or 600 g/kg of diet) and 2 levels of XAP (0 or 0.25 g/kg) were used in experiment 1. Six diets consisting of 3 levels of wheat-DDGS (200, 400 or 600 g/kg of diet) and 2 levels of phytase (0 or 1000 FTU/kg) were used in experiment 2, whereas four diets consisting of a NFD and an assay diet, both diets without- or with supplemental protease were used in experiment 3. In experiment 1, increasing the dietary inclusion of wheat-DDGS from 0 to 600 g/kg decreased linearly (P < 0.05) DM and energy retention. There was wheat-DDGS × XAP interaction (P < 0.05) for dietary AME and AMEn. Dietary AME and AMEn values decreased linearly (P < 0.001) as the level of wheat-DDGS increased in the diets without XAP, whereas there was no effect of increasing wheat-DDGS level on dietary AME or AMEn for the XAP-supplemented diets.
14
Chaudhry, Saeed Mukhtar. "Processing and nutritional value of poultry litter and slaughter house by-product". Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-09162005-115004/.
Testo completo
15
Vinall, Sarah A. J. "A critical look at nutritional value of commercials on the Nickelodeon Network". Scholarly Commons, 2008. https://scholarlycommons.pacific.edu/uop_etds/689.
Testo completoAbstract (sommario):
Food advertising aimed at children in America has been proven to directly impact food preferences, eating behavior and brand loyalty of youth (Story & French, 2004). The purpose of this study was to evaluate the content of television commercials that occurred during children's programming on the popular children's network Nickelodeon. This study examined the frequency, nutritional content and overall advertising techniques associated with food, beverage and restaurant commercials. It also assessed the degree to which children are being exposed to the promotion of unhealthy food, beverage restaurant commercials.
This study examined commercials that aired on the Nickelodeon Network between Monday, August 11 through Friday, August 15, 2008 between 3 p.m. and 5 p.m. on the Comcast Cable System in Stockton, California. The programming was recorded on a VHS tape and then later reviewed and analyzed. Each commercial was examined in the following areas: nutritional content; slogan; branded characters; premium; link to a movie and healthy message.
This study demonstrated that 40.65% of the commercials airing between 3 p.m. and 5 p.m. on the Nickelodeon television network are for food, beverage and/or restaurants. Twenty-six percent of food, beverage and restaurant commercials met or exceeded the daily recommended levels of fat, added sugars, and sodium, and fell short of providing essential nutrients as outlined by the United States Department of Agriculture (USDA) (United States Department of Agriculture, 2008).
The results of this study indicate that a considerable amount of food commercials targeting children as consumers. Government regulation seems unlikely due to the First Amendment, rights to free speech. This study points to several suggestions for advertisers, advocates, Children's Advertising Review Unit (CARU) teachers and parents to address the issue of advertising to children. Some of the suggestions include stricter self-regulation, education and parental responsibility.
16
Forster, Lance Allen. "Nutritional value of flat pea hay fed to sheep at different levels". Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43855.
Testo completoAbstract (sommario):
Two experiments were conducted with sheep to determine the nutritional value of 'Lathco' flatpea (Lathyrus sylvestris) hay. In experiment 1, a finishing trial was conducted with 50 group fed crossbred lambs (25 ewes and 25 wethers) fed diets consisting of 70% chopped forage and 30% ground corn grain for 70 d. Five pens of five wethers and five pens of five ewes were selffed diets in which the forage consisted of 100:0, 75:25, 50:50, 25:75, and 0:100 proportions of alfalfa (Medicago sativa L.) and flatpea hay. Feed efficiencies decreased linearly (P<.05) as flatpea increased in the diet. Linear decreases (P<.05) were obtained in kidney and pelvic fat, backfat, leg conformation, and yield grade with increased flatpea in the diet. Blood urea-N (BUN), ruminal pH and NH3-N increased (P<.005) as proportion of flatpea increased. Total volatile fatty acid (VFA) and acetate concentration decreased linearly (P<.005) and propionate, isovalerate, and valerate levels increased linearly (P<.01) with increased proportions of flatpea hay. In experiment 2, 30 wether lambs were fed diets consisting of 100:0, 75:25, 50:50, 25:75 and 0:100 proportions of chopped alfalfa and flatpea hays in a digestion trial. Neutral detergent fiber (NOE), acid detergent fiber (ADE), cellulose, hemicellulose and energy digestibilities decreased linearly (P<.Ol) with increased levels of flatpea hay. Nitrogen retention was not different between sheep fed the different diets. Apparent absorbtion and retention of Ca decreased linearly (P<.05) with increased level of flatpea hay Ruminal pH and NHa-N, and BUN increased linearly (P<.OOl) as flatpea was increased in the diet. Ruminal total VEA, acetate and acetate to propionate ratio decreased linearly (P<.001) and propionate, isobutyrate, isovalerate, and valerate levels increased linearly (P<.001) as level of flatpea increased.
Master of Science
17
Wakeham, Andres I. "Preservation and nutritional value of caged layer waste treated with different preservatives". Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/64568.
Testo completoAbstract (sommario):
Two experiments were conducted with caged layer waste. In the first experiment fresh waste was treated with: no additive, 2% formaldehyde, 3% sodium metabisulfite, 1% formaldehyde and 2% propionic acid, 3% formic and 2% propionic acids and stored in polyethylene lined 208 liter metal drums. In experiment II waste treated with 2% formaldehyde, 1 % formaldehyde and 2% prop ionic, 3 % formic and 2% propionic (w/w), stored for at least 42 d, used in a metabolism trial as N supplements to a basal diet fed to sheep.
The formaldehyde, formaldehyde/propionic and formic/propionic treatments eliminated the bacterial decomposition of the waste and no undesirable fermentation was observed on the stored material. Waste treated with no additive or sodium metabisulfite underwent putrefaction.
Nitrogen supplementation of a basal diet with treated caged layer wastes improved apparent digestibility of crude protein and N retention in sheep fed these diets.
Supplementation of a basal diet with chemically treated caged layer waste improves the nutritional value of the diet which suggests that caged layer waste is efficiently utilized as a N source by ruminants when used as a protein supplement.Master of Science
18
Jerónimo, Eliana Alexandra Sousa. "Dietary manipulation to inprove the nutritional value of lipids from lamb meat". Doctoral thesis, Universidade de Évora, 2011. http://hdl.handle.net/10174/15306.
Testo completoAbstract (sommario):
A carne de borrego é caracterizada por altos teores em ácidos gordos (AG) saturados e baixos níveis de ácidos gordos polinsaturados (AGPI), propriedades que são consideradas prejudicais para a saúde humana. Para atender às recomendações nutricionais é necessário melhorar a sua composição em AG. A principal motivação desta tese foi explorar algumas estratégias nutricionais que permitam melhorar o valor nutricional da fracção lipídica da carne de borrego. Os resultados obtidos mostram que a suplementação das dietas com óleos vegetais ricos em AGPI é uma abordagem eficaz para reduzir a saturação da carne de borrego e aumentar o seu conteúdo em AGPI. Além disso, a suplementação com mistura de óleos de girassol e de linho permitiu aumentar simultaneamente o conteúdo em isómeros conjugados do ácido linoleico e em AGPI n-3 de cadeia longa. A inclusão de bentonite sódica e de Cistus ladanifer em dietas suplementadas com óleo também mostrou ser uma boa abordagem para melhorar a composição em AG da carne de borrego; ABSTRACT:
Dietary manipulation to improve the nutritional value of lipids from lamb meat
Lamb meat is characterized by high contents of saturated fatty acids and low levels of polyunsaturated fatty acids (PUFA), properties that are regarded as being negative to human health. To meet the nutritional recommendations is necessary improving the fatty acid (FA) composition of lamb meat. The main motivation of this thesis was explored some nutritional strategies that allows improve the nutritional value of lipid fraction from lamb meat. Data presented here show that supplementation of diets with vegetable oils rich in PUFA is an effective approach to decrease the saturation of lamb meat and increase its content in PUFA. Moreover, supplementation with blend of sunflower and linseed oils allowed increase simultaneously meat content in conjugated isomers of linoleic acid and n-3 long chain PUFA. Inclusion of sodium bentonite and Cistus ladanifer in oil supplemented diets also showed to be a good approach to improve the FA composition of lamb meat.
19
Fellah, Abdulmunam Mohamed. "The nutritional value and toxic properties of buffalo gourd (Cucurbita foetidissima) plant". Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185245.
Testo completoAbstract (sommario):
Buffalo gourd (BG), Cucurbita foetidissima, vine contains a material that was toxic to mice. Extracting the vine with either water or ethanol greatly improves the performance of the mice. However, water treatment of the vine had removed the bitter substances and gave a better response than ethanol extraction which partially reduced these materials. Chicks received up to 10% of BG seeds in a soybean meal diet had no significant change in their growth as compared to those fed control diet. However, as the concentration of the seeds increased to 20% or above, a significant reduction in chicks performance were found in comparison to the soybean meal. Signs of toxicities which caused high mortality rate were also observed in those chicks. Cleaning and washing of BG seeds did not improve chicks performance as compared to those on uncleaned-unwashed seeds. Birds fed BG hulls were not significantly different than the control diet and showed no signs of neuromuscular abnormalities or death. Feeding defatted seeds and defatted embryo diets depressed the growth. The addition of 24% of BG seeds to the regular soybean meal diet showed no difference in growth as compared to the control birds. The neuromuscular abnormalities were observed only in birds fed defatted seeds, defatted embryo and whole seed diets but not hulls or whole seed uncleaned diets. This raises a serious issue of just what is causing these neuromuscular problems in some diets and not all of them. These abnormalities disappeared after the chicks were shifted back to the regular starter diet. Incorporation of 10% of the whole BG roots in practical chick ration significantly depressed growth. Toxicity problems were also observed in these chicks. Water extraction of the roots improved performance and appeared to reduce the bitter material in the diet and the incidence of mortality when compared to those fed the dried roots. A preliminary study using silage as prepared from BG forage has shown no palatability problems when fed to young heifers. Incorporation of milo with BG forage did not improve the palatability of the silage. This was a great improvement in feed intake values when compared to the feeding of fresh cut forage to calves or cows.
20
Al-Mamary, M. A. "Glucosinolate in rapeseed : toxic effects upon the liver and thyroid gland". Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.255853.
Testo completo
21
Capper, Brian Stephen. "Factors influencing the nutritive value of barley straw for ruminants". Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238166.
Testo completo
22
Widyaratne, Gemunu Prasanna. "Characterization and improvement of the nutritional value of ethanol by-products for swine". University of Saskatchewan, 2005. http://library2.usask.ca/theses/available/etd-12142005-151836/.
Testo completoAbstract (sommario):
The nutritional value of distillers dried grains with solubles (DDGS) has not been assessed in swine. The nutritional value of corn and wheat DDGS, and possibilities to improve the nutritional value of wheat DDGS were for swine were investigated in two studies. In study 1, two experiments were conducted to determine digestibility and digestible contents of energy, amino acids (AA) and P in corn and wheat DDGS and wheat grain, together with N and P excretion and growth performance in grower-finisher pigs. In experiment 1, 12 barrows (64.6 ± 6.4 kg) were fitted with ileal T-cannulae and had restricted access (2.6 x maintenance) to a wheat control diet or one of three diets with 40% corn, wheat+corn (4:1) or wheat DDGS. For energy, apparent total tract digestibility was highest for wheat (85%; P < 0.05) and did not differ among DDGS (77 to 79%; P > 0.10). Total tract digestible energy (DE) was highest for corn DDGS (4292 kcal kg-1 DM; P < 0.05) and tended to differ among wheat+corn and wheat DDGS and wheat (4038, 4019, and 3807, respectively; P = 0.06). For lysine, apparent ileal digestibility (AID) was highest for wheat (71%; P < 0.05) and did not differ among DDGS (59 to 63%; P > 0.10). The apparent ileal digestible lysine content was highest for corn DDGS (0.51% DM; P < 0.05), intermediate for wheat+corn and wheat DDGS (0.45 and 0.42), and lowest for wheat (0.37%). For P, total tract digestibility was lowest for wheat (15%; P < 0.05) and did not differ among DDGS samples (53 to 56%; P > 0.10). Total N excretion was highest for wheat+corn and wheat DDGS (55 and 58 g d-1; P < 0.05), intermediate for corn DDGS (44) and lowest for wheat (36). Total P excretion did not differ among DDGS (11 g d-1) and was lowest for wheat (8; P < 0.05). In experiment 2, 100 pigs (52.0 ± 3.3 kg) were fed a wheat-pea control diet or one of three 25%-DDGS (corn, wheat+corn or wheat) diets (3.375 Mcal DE kg-1; 2.50 g AID lysine Mcal-1 DE) for 5 wk. Overall, average daily feed intake (ADFI) and daily gain (ADG) were higher for wheat than DDGS (P < 0.05) but feed efficiency did not differ (P > 0.10). In summary, the nutritional value of wheat DDGS for swine is higher than wheat and lower than corn DDGS and feeding DDGS reduced growth performance, partly via a reduced ADFI, indicating that anti-nutritional factors in DDGS require further investigation.
In study 2, the effect of xylanase supplementation of wheat DDGS on nutrient digestibility and nutrient excretion was evaluated in grower-finisher pigs. Wheat-based diets with or without 40% wheat DDGS were tested with or without supplementary xylanase (4,000 U kg-1 feed) as a 2 x 2 factorial arrangement in a repeated Latin square design using eight barrows (29.4 ± 2.0 kg) fitted with ileal T-cannulae. Following a 6-day acclimation, faeces and urine were collected for 3 d, and ileal digesta for 2 d. The apparent ileal energy digestibility and DE content were not affected either by ingredient or xylanase (P > 0.05). The total tract energy digestibility and DE content were affected by ingredient (P > 0.05), but not by xylanase (P > 0.05). The total-tract energy digestibility was higher for wheat, but DE content was higher for wheat DDGS. The AID of arginine, isoleucine, leucine, phenylalanine, threonine, tryptophan and total AA were higher (P < 0.05), and of cysteine, histidine and lysine were similar (P > 0.05), and SID of phenylalanine was higher (P < 0.05), and of the other AA was similar (P > 0.10) for wheat DDGS compared to wheat. Supplementary xylanase improved AID and SID of most of the indispensable AA in wheat (P < 0.05), but not in wheat DDGS (P > 0.05). The apparent and standardized ileal AA contents were affected by ingredients (P < 0.05), but not by xylanase (P > 0.05). Digestible AA contents were higher for wheat DDGS than for wheat. The digestibility and digestible content of P were affected by ingredient and xylanse (P < 0.05). The P digestibility and digestible P contents were higher for wheat DDGS compared to wheat. Neither ingredient nor supplementary xylanase affected DM intake (P > 0.05). The DM excretion on daily basis and as a percentage of intake were affected by ingredient (P < 0.05), but not by xylanase (P > 0.05). Ingredients affected all N and P variables (P < 0.05), except percentage retained for both nutrients (P > 0.05). None of N variables (P > 0.05), but P intake and, retention on daily basis and as a percentage of intake were affected by xylanase (P < 0.05). The DM excretion and N and P intake, excretion and daily retention were higher for wheat DDGS compared to wheat. Lack of beneficial response to supplementary xylanase might be due to inappropriate enzyme level or insufficient substrate level of wheat DDGS. In addition, unidentified factors associated with fermentation and drying processes might constrain the nutritional value of wheat DDGS. Further studies are required to determine the proper xylanase inclusion level and/or to identify the factors associated with reduced nutrient digestibility of wheat DDGS.
23
Nanton, Dominic André. "Nutritional value of marine harpacticoid copepods as live food for marine fish larvae". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq24887.pdf.
Testo completo
24
Masey, O'Neill Helen Victoria. "Influence of storage and temperature treatment on nutritional value of wheat for poultry". Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/14130/.
Testo completoAbstract (sommario):
Worldwide production of wheat in 2007 was 787 million (IGC 2008). Due to its importance in the world commodity market, there has been much research into the potential problems of weather damage to wheat, particularly with reference to bread making. The current project aimed to address three major research areas. Firstly, the effects of heat treatment in relation to the nutritional value of weather damaged wheat were investigated. It appears that drying at 100°C may increase Coefficient of Apparent Digestibility of starch (CAD). Some flour samples that were heated to 100°C failed to demonstrate expected hydration properties that would normally be associated with increased digestibility. They also appear to maintain their crystalline order. Therefore, an increase in CAD is not necessarily related to changes in starch structure and is probably more likely due to modification of non-starch components such as protein. A hypothesis is discussed, that proteins may form a film that protects the starch until the protein is digested by endogenous chick proteases. The precise drying temperature is critical, as at 85°C, digestibility may be decreased, possibly due to crystalline perfection. Apparent Metabolisable Energy (AME) did not follow starch digestibility. Secondly, it was hypothesised that the Rapid Visco Analyser (RVA) may be able to quantify amylase activity and predict nutritional value of wheat samples. Interestingly, unexpectedly high levels of amylase were observed in some wheat samples. This activity remained despite two years in ambient storage and temperature treatment of up to 100°C. These high levels of amylase activity did not appear to affect CAD, presumably due to deactivation in the acidic conditions of the proventriculus. There were some highly significant relationships between in vivo parameters and in vitro RVA parameters, particularly between Peak Viscosity (with an amylase inhibitor) and Coefficient of Duodenal Digestibility or AME (P
25
Obamehinti, Johnson Muftau. "Effect of treating corn stover with aqueous ammonia and urea on nutritional value". Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45904.
Testo completoAbstract (sommario):
Experiments were conducted to study the effect of treatment of rectangular bales of corn stover with aqueous ammonia and urea solutions. The stacks were covered with polyethylene sheets for 129 d, after which they were uncovered, aerated and sampled for laboratory analyses.
Master of Science
26
Diamanti, Jacopo. "Quality, nutritional quality and nutraceutical value as a new task for strawberry breeding". Doctoral thesis, Università Politecnica delle Marche, 2011. http://hdl.handle.net/11566/241922.
Testo completoAbstract (sommario):
Negli ultimi anni i consumatori hanno aumentato l’attenzione rivolta agli aspetti nutrizionali e salutistici (vitamine, sali minerali, antiossidanti, ecc.) legati ai prodotti ortofrutticoli. Il consumo di frutta è stato ampiamente considerata possedere importanti caratteristiche salutari, legate in particolar modo al contenuto di composti antiossidanti, i quali svolgono, all’interno del corpo umano, un’azione protettiva contro le reazioni di ossidazione cellulare. Frutta e verdure contengono composti antiossidanti, oltre alle vitamina C, vitamina E e ai carotenoidi, i quali contribuiscono alla loro capacità antiossidante totale, come i composti fenolici (flavonoidi, antociani, tannini, ellagitannini, ecc). I frutti rossi sono fra i frutti più ricchi in composti fitochimici a carattere antiossidante, tra i frutti rossi la fragola è uno dei più attrattivi, grazie al suo aspetto e alle sue caratteristiche aromatiche, ma ultimamente i consumatori hanno concentrato le loro attenzioni sulle caratteristiche nutrizionali del frutto di fragola. Di conseguenza i ricercatori hanno concentrato il loro interesse verso le caratteristiche nutrizionali del frutto di fragola, allo scopo di caratterizzare i composti bioattivi del frutto per capire come tali composti vengono sintetizzati all’interno della matrice del frutto.
È in costante aumento l’interesse rivolto verso i multipli fattori genetici e ambientali che interagiscono sulla produzione e accumulo dei composti nutrizionali del frutto di fragola, anche se tali fattori non sono tenuti in considerazione durante la fase di commercializzazione. Il presupposto di “frutto funzionale” sottolinea che i composti bioattivi presenti nel frutto siano efficaci per la salute del consumatore. La valutazione rigorosa delle prove scientifiche richiede la definizione di un set di criteri e metodi per la valutazione delle caratteristiche nutrizionale del frutto di fragola. Le metodologie per la determinazione dei composti bioattivi dei frutti possono essere considerate strumenti veloci e affidabili per lo screening di larghe popolazioni ottenute da programmi di miglioramento genetico al fine di ottenere genotipi di fragole ad elevato valore nutrizionale.
La ricerca sviluppata durante il corso di dottorato è stata incentrata nello 1) sviluppo di metodologie standardizzate di analisi nutrizionale sul frutto di fragola valutata su tre campi di collezione germoplasma fragola; 2)valutazione della qualità nutrizionale di nuovi genotipi di fragola generati da programma di miglioramento genetico utilizzando re-incroci interspecifici di F. virginiana spp. glauca e incroci intra-specifici di F. x ananassa, al fine di produrre nuovo materiale genetico con elevate caratteristiche nutrizionali; 3) validazione della capacità antiossidante del frutto di fragola valutata in vivo su ratti sottoposti ad elevato stress ossidativo.
I risultati ottenuti tramite questo approccio multidisciplinare conferma l’importanza dello sviluppo di metodologie di analisi rapide ed efficaci per la valutazione delle componenti nutrizionali del frutto di fragola, grazie al maggior interesse che le caratteristiche nutrizionali stanno acquistando. La valutazione delle caratteristiche nutrizionali nelle collezioni germoplasma fragola europee conferma l’importanza del genotipo riguardo alla composizione dei composti bioattivi nel frutto, ma anche il ruolo importante svolto dalle condizioni ambientali e dalla regionalità. Inoltre è confermata l’importanza delle specie selvatiche come nuovo strumento nello sviluppo di programmi di miglioramento genetico al fine di incrementare la qualità nutrizionale del frutto. In fine è provata l’efficacia del potere antiossidante del frutto di fragola contro il danno provocato dallo stress ossidativo in vivo, ance se efficacia dell’effetto antiossidante è strettamente legato con i composti bioattivi presenti nel frutto e conseguentemente con il genotipo.
Questo tipo di approccio multidisciplinare permetterà il licenziamento di nuove varietà capaci di offrire frutti di alta qualità e sicuri per il consumatore.In recent times increasing attention has been paid by consumers to the health and nutritional aspects (vitamins contents, mineral elements, antioxidants, etc.) of horticultural products. Fruits and vegetables contain antioxidant compounds, in addition to vitamin C or E and carotenoids, that significantly contribute to their total antioxidant capacity, such as phenolic acids (flavonoids, anthocyanins, tannins ellagitannins ecc.). Berry fruits are one of the richest sources of antioxidant phytochemicals encountered. Among berries strawberry fruit is one of the more attractive, due to its aspects and taste, but lately consumers have also focused their attention on strawberry fruit health-related compounds. For such reason researchers have focus their attention on strawberry fruit nutritional attributes, characterizing fruit bioactive compounds and understanding the physiological development of such compounds. Increasing awareness on multiple genetic and environmental factors affecting production and accumulation of bioactive compounds is observed among agronomic investigators, but these factors are rarely taken in account when fruit is marketed. The assumption underlying the ‘functional fruit’ is that the bioactive compounds in fruit are efficacious for the improvement of health. Rigorous and unprejudiced evaluation of the scientific evidence requires a defined set of criteria and methods of evaluation. The methods available for detecting fruit bioactive compounds can be suggested as fast and reliable tools for screening large breeding populations for high berry nutritional quality. The research carried on in these three years was focused on 1) the development of standardized methods for the evaluation of fruit bioactive compounds of European strawberry fruit germplasm collections, to identify genotypes able to provide new gene sources for increasing fruit nutritional value; 2) the evaluation of fruit nutritional quality of new strawberry genotypes generated by a breeding program based on the comparison of offspring populations originated by inter-specific backcross of F. virginiana spp.glauca and F. x ananassa intra-specific cross, with the aim to produce new genetic material with improved fruit nutritional quality; 3) validation of strawberry fruits antioxidant capacity against oxidative stress in vivo by a strawberry fruit supplementation in a sixteen week long term diet in rats. The results obtained by this multidisciplinary approach state the importance of developing methodologies of fruit nutritional evaluation fast and reliable, because of the main role that nutritional quality is acquiring. The nutritional evaluation of European strawberry collections confirm the importance of genotype in regards to bioactive compounds composition, but also the main role played by environmental conditions and location. Furthermore, the importance of wild genetic resources as new implement in strawberry breeding program aimed to improve fruit nutritional quality, is confirmed. Finally, the efficacy of strawberry antioxidant capacity against oxidative damage in vivo, is stated, even if the effect is strictly linked with the fruit bioactive composition and consequently strawberry genotype. This multidisciplinary approach will allow the release of new varieties able to offer better quality and consumer safety.
27
Shahnaseri, Mahnaz, of Western Sydney Hawkesbury University, of Science Technology and Environment Faculty e School of Food Science. "The effect of cooking method upon iron and zinc bioavailability in rice". THESIS_FST_SFH_Shahnaseri_M.xml, 2001. http://handle.uws.edu.au:8081/1959.7/695.
Testo completoAbstract (sommario):
Prevention of iron deficiency rather than treatment is preferred by most nutritionists. The presence of a maximal iron supply is not advised because an excessive or unnecessary iron supplement may have biologically adverse effects, such as impaired immune resistance or negative interaction with other trace elements. All cereals and most vegetables contain phytate (inositol hexaphosphate) which can bind iron and zinc and reduce their biological availability. The amount of iron available for absorption in any given diet depends to a large extent on the composition of the diet, e.g., the presence of vitamin C and haem iron, and the absence of phytate. Rice is one of the most important staples in the Iranian diet and, in fact, rice, for most Iranians, is not a side dish but a main dish to which other foods or ingredients are added. An awareness of the effects of cooking method on nutrient content is important because cooking techniques influence the overall quality of a group's diet. The goal of this study is to determine the bioavailability of iron and zinc in traditional Iranian rice dishes and to assess the effect of traditional methods of cooking rice upon iron and zinc bioavailability. Iranian migrants residing in Sydney were surveyed in order to determine their food habits and traditional cooking methods, for the assessment of their effects upon the bioavailability of iron and zinc in Iranian rice dishes. Rice contains phytate, which is a potent inhibitor of iron absorption. The amount of phytate in rice depends on whether the rice is polished or not. The pre-cooking treatment such as soaking can also influence the phytate content of the rice. Soaking prior to cooking also reduced the amount of ion and zinc. The inhibitory effect of phytate is also overcome by adding different herbs, vegetables and legumes used traditionally in rice dishes cooked by Iranians. Herbs or vegetables such as coriander, parsley and cauliflower, used in Iranian rice dishes, increased the bioavailability iron and zinc. Results obtained from this research show that method of cooking, as well as the food mixture, is very important for the absorption of iron and zinc from the dietDoctor of Philosophy (PhD)
28
Koyama(Ito), Ayana. "Analysis of Nutritional Components of Spinach Under Root Chilling Stress". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/264639.
Testo completo
29
Bosch, Adina Cornelia. "Investigation of the chemical composition and nutritional value of smoothhound shark (Mustelus mustelus) meat". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20261.
Testo completoAbstract (sommario):
Thesis (MSc Food Sc)--Stellenbosch University, 2012.ENGLISH ABSTRACT: The aim of this study was to determine the proximate composition of five individual body sites of the Mustelus mustelus shark in order to evaluate the cross carcass variation of the individual proximate components (moisture, protein, lipid, ash) of the meat. This variation was determined in order to find a representative sample of the edible part of the shark (fillet and body flap). Secondly, this sample representing the entire shark fillet was used to investigate the endogenous factors (gender, size and life cycle stage) and their effects on the individual proximate components and other meat components (amino acids, fatty acids, minerals, histamine and mercury contents). Finally, all this data was combined to describe the average chemical composition and nutritional value of M. mustelus meat. None of the proximate components showed any variation between the different fillet positions. This indicated that the fillet is homogenous and samples for chemical analyses can be taken anywhere on the fillet as representative of the entire fillet. It was found that all three main effects (gender, size and life cycle stage) did not have major influences on most of the components of the chemical composition of M. mustelus meat analysed. Higher fatty acid levels (SFA, MUFA and PUFA) were observed in large females than in large males as well as in non-pregnant large females compared to pregnant large females. According to statistical analysis, large males had higher total mercury levels than large females. The only component affected by size variation was the fatty acids, showing a trend to decrease in quantity before maturity was reached. Variation due to life cycle stages was mostly evident in the fatty acid component with some small effects on two mineral components, aluminium and copper, which had slightly higher levels in pregnant large females than in non-pregnant large females. M. mustelus meat has an average proximate composition of 75% moisture, 23% protein, 1.6% lipids and 1.4% ash (weight per wet weight). The protein is, however, an over-estimation of the true protein value as the meat contains significant amounts of non-protein nitrogen (NPN) in the form of urea which contributes to the N concentration. M. mustelus meat is a good source of some essential amino acids, especially lysine and threonine (78% of the daily requirements for an adult in a 100g portion), but low in minerals. The meat has a healthy lipid content with a good ratio (>0.45) of PUFA:SFA (0.83) as well as a healthy (<4) n-6:n-3 fatty acid ratio of 0.39. The histamine content was very low or not detectable but some samples contained total mercury values above the maximum safe limit. Although further research is needed for some meat components, these results are a valuable contribution to the new South African Food Composition Tables being compiled.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die proksimale samestelling van die vleis vanaf vyf afsonderlike posisies op die liggaam van die Mustelus mustelus haai te bepaal. Sodoende is die variasie, met betrekking tot die verskillende proksimale komponente (vog, proteïen, lipiede en as), in terme van die totale karkas, bepaal. Die proksimale variasie is bepaal om vas te stel hoe ʼn verteenwoordigende monster van die totale karkas geneem kan word. Gevolglik is hierdie verteenwoordigende monster gebruik om die effek van geslag, grootte en die verskillende fases van die lewens-siklus op die afsonderlike proksimale komponente asook ander vleis komponente (aminosure, vetsure, minerale, histamien en kwik inhoud) te ondersoek. Laastens is al hierdie inligting gebruik om die algemene samestelling en voedingswaarde van M. mustelus vleis te bespreek. Geen van die proksimale komponente het enige variasie getoon tussen afsonderlike liggaamsposisies nie. Hierdie resultaat dui daarop dat die vleis van ʼn M. mustelus haai homogeen is regoor die karkas en dat ʼn vleis monster vanaf enige posisie op die karkas geneem kan word as ʼn verteenwoordigende monster. Daar is gevind dat geslag, grootte en fase van die lewens-siklus geen merkwaardige invloed het op die vleis se samestelling nie. Hoër vetsuur konsentrasies (versadigde, monoonversadigde en poli-onversadigde vetsure) is gevind in groot vroulike haaie en nie-dragtige vroulike haaie as in groot manlike haaie en dragtige vroulike haaie onderskeidelik. Statisties, het groot manlike haaie hoër vlakke van totale kwik as groot vroulike haaie. Die enigste vleis komponent wat beïnvloed is deur die grootte van die haai, is die vetsure, wat verminder het voor volwassenheid bereik is en dan weer vermeerder soos die haai groter word. Variasie as gevolg van die verskillende fases van die lewens-siklus is meestal gevind in die vetsuursamestelling, en die minimale het ook gevarieer ten opsigte van die elemente aluminium en boor wat effense hoër vlakke getoon het in dragtige haaie as in nie-dragtige haaie. M. mustelus vleis het ʼn gemiddelde proksimale samestelling van 75% vog, 23% proteïen, 1.6% lipiede en 1.4% as (nat massa). Die proteïen waarde is ʼn oorskatting van die ware proteïen waarde as gevolg van hoë nie-proteïen stikstof in die vorm van ureum wat bydra tot die totale stikstof inhoud. M. mustelus vleis blyk ʼn goeie bron van sommige essensiële aminosure soos lisien en treonien (78% van die daaglikse aanbevole dosis), maar laag in mineraal inhoud. Die vleis het ʼn gesonde vet inhoud met ʼn goeie (>0.045) poli-onversadigde:versadigde vetsuur verhouding (0.83) asook ʼn gesonde (<4) omega 6 tot omega 3 vetsuur verhouding van 0.39. Die histamien inhoud van die vleis was baie laag of onder die meetbare limiet, maar sekere monsters het ʼn totale kwik inhoud getoon wat bo die maksimum veilige limiet is. Hoewel verdere navorsing ten opsigte van sekere van die vleis komponente vereis word, lewer hierdie resultate ʼn waardevolle bydrae tot die nuwe Suid-Afrikaanse voedsel samestellings tabelle wat tans opgestel word.
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Mahmood, Sultan. "Chemical treatment of salseed meal : effects on nutritional value and physiological effects in the fowl". Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239024.
Testo completo
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Moulay, Leila. "Physiological studies in rats of the nutritional value of a cocoa powder derived bulking agent". Thesis, University of Salford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357121.
Testo completo
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Monteiro, Ana Cristina Saragoça Melgado Gonçalves. "Relationship between Portuguese consumer preferences and textural properties, chemical composition and nutritional value of beef". Doctoral thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/4857.
Testo completoAbstract (sommario):
Tese de Doutoramento em Ciências Veterinárias. Especialidade de Produção AnimalBeef is a nutritionally rich product with a high economic value. However in the last decades beef has been target of negative publicity by the media, mainly due to the high content of cholesterol as well as saturated and trans fatty acids (FA). The increasing number of food scares across the Europe over the last years has increased even more consumers’ concerns about beef quality and safety. Despite the health concerns beef sensory properties still remain the main purchasing and repeat purchasing criteria for the consumers. Tenderness has been considered the major palatability characteristic of beef and defines its commercial value. However, tenderness variability has been considered a major problem to the beef industry. In this context, the aim of this proposal was to ascertain the organoleptic properties and lipid nutritional value of beef and to relate them with the Portuguese consumer` preferences. The experimental work was divided in two trials. In the first trial, the meat quality and lipid nutritional value from “Vitela Tradicional do Montado”-PGI veal, Mertolenga-PDO veal and Mertolenga-PDO beef were studied. The results suggested that the three products are not very different, but the two veal types are more alike, which means that age had a more powerful effect than the crossbred or gender. Nevertheless, despite the similarity in FA profile and of the production systems of the animals sampled, it was possible to discriminate the meat types. Moreover, the PGI veal seems to have higher variability than the other two meat types studied. In the second trial, three beef types from the Portuguese market place, Carnalentejana-PDO, imported from Brazil and national undifferentiated beef, were studied and compared to characterise nutritional value and variability of beef lipids as well as the organoleptic properties and their variability. We also intended to relate the sensory attributes with instrumental measurements in order to realise if it is possible to predict sensory evaluation through instrumental measurements. Brazilian beef had the highest lipid nutritional value and lipid stability as this beef presented higher contents of α-tocopherol, β-carotene, CLA and PUFA. The data indicated that all beef types seem to have α-tocopherol values high enough to inhibit lipid oxidation and discoloration. Energy intake was calculated for the main FA and compared with the recommended daily intake. All beef types seem to have low cholesterol and SFA contents. Concerning the relation between the sensory attributes and the instrumental measurement, sensory tenderness was correlated with WBSF but not with TPA hardness. Nevertheless, TPA chewiness was well correlated with sensory tenderness indicating TPA usefulness to give addicional information of beef texture. Off-flavour was the ix main determinant of overall acceptability and Brazilian beef presented the highest and lowest values, respectively. Brazilian beef also had the lowest juiciness score, indicating that this beef type despite having the best lipid nutritional value can be rejected due to it sensory attributes. All beef types were considered slightly to moderately tender regarding WBSF and sensory tenderness mean values. National undifferentiated beef seem to have higher variability in the colour measurements, whilst Carnalentejana-PDO seems to depicted higher tenderness variability. Despite having mean values in the aforementioned attributes that indicates a consumer high acceptability, the high variability in both cases can be detrimental in the moment of sale.
RESUMO - Relação entre as preferências do consumidor português e a textura, composição química e valor nutricional da carne de bovino - A carne bovina é um produto nutricionalmente rico e de elevado valor económico. No entanto, nos últimos anos tem sido alvo de publicidade negativa por parte da comunicação social devido ao seu conteúdo em colesterol e em ácidos gordos saturados e trans. O crescente número de surtos alimentares na Europa aumentou a preocupação dos consumidores quanto à segurança e qualidade alimentar. No entanto, apesar das referidas preocupações, os atributos sensoriais ainda permanecem a principal razão que leva os consumidores a comprar e a repetir a compra de carne de bovino. A tenrura tem sido considerada o atributo mais importante da carne bovina e define o seu valor comercial, mas a sua variabilidade tem representado um problema para a indústria. Neste contexto, o objectivo deste trabalho foi determinar as propriedades organolépticas e o valor nutricional da fracção lipídica da carne bovina e relacioná-las com as preferências dos consumidores. O trabalho experimental consistiu em dois ensaios. No primeiro ensaio foram estudados a qualidade organoléptica e o valor nutricional da fracção lipídica da carne de vitela “Vitela Tradicional do Montado”-IGP e Mertolenga-DOP e do novilho Mertolenga-DOP. Os resultados sugerem que as duas vitelas têm composições similares, o que pode significar que o efeito da idade foi maior do que o efeito da raça ou género. Apesar das semelhanças do sistema de produção e no perfil lipídico as três carnes foram bem discriminadas. No segundo ensaio foram estudados a qualidade organoléptica e o valor nutricional dos lípidos das carnes de bovino Carnalentejana-DOP, importada do Brasil e nacional indiferenciada. Também aqui se pretendeu prever a qualidade sensorial das carnes com base nas medições instrumentais. Todos os tipos de carne apresentaram baixo teor em colesterol, e teor em α-tocoferol suficiente para inibir a oxidação lipídica e a descoloração. A carne Brasileira apresentou o melhor valor nutricional do perfil lipídico e potencial anti-oxidante, visto ter apresentado conteúdos superiores em α-tocoferol, β-caroteno, CLA e ácidos gordos poliinsaturados. A ingestão de energia foi calculada para os ácidos gordos mais importantes e comparada com as recomendações de ingestão diárias. Todos os tipos de carne apresentaram baixo conteúdo em colesterol e ácidos gordos saturados. Os atributos sensoriais apresentaram correlações baixas com os parâmetros instrumentais, e apenas a força de corte se correlacionou com a tenrura sensorial. No entanto, a tenrura sensorial correlacionou-se com a mastigabilidade indicando que o TPA pode ser útil, dando informação adicional sobre a textura da carne. O off-flavour foi o principal determinante da xi aceitabilidade da carne, apresentando a carne Brasileira os valores mais e menos elevados, respectivamente. A carne Brasileira foi também a menos suculenta, indicando que apesar de apresentar o melhor valor lipídico pode, no entanto, ser rejeitada pelas suas características sensoriais. Todas as carnes foram consideradas ligeira a moderadamente tenras, tendo em conta os seus valores de força de corte e de tenrura sensorial avaliada pelo painel de provadores. As carnes nacionais apresentaram heterogeneidade da sua composição química, a Carnalentejana-DOP na tenrura e a nacional indiferenciada na cor, o que é indesejável e pode condicionar a sua comercialização, pelo que este aspecto deve ser melhorado.
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Sherfy, Mark Huffman. "Nutritional Value and Management of Waterfowl and Shorebird Foods in Atlantic Coastal Moist-Soil Impoundments". Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/26575.
Testo completoAbstract (sommario):
The mid-Atlantic coast region, an area of continental significance to migratory and wintering waterfowl and shorebirds, contains numerous moist-soil impoundments that are managed for waterbirds. Positive relationships between nonbreeding body condition and subsequent survival and reproduction have been documented for waterfowl, yet few evaluations of habitat management consider nutritional value of foods. I assessed 2 types of impoundment manipulation, using nutritional data as a basis for evaluation.Invertebrate and plant seed production were measured in disced and control plots in impoundments at Back Bay National Wildlife Refuge. Seed production was higher (P = 0.0614) in disced (1052 ± 468 kg / ha) than in control (529 ± 226 kg / ha) plots. Discing produced higher Chironomid larva abundance during spring, and higher abundance of Amphipods and non-Chironomid Diptera during fall. Waterbird predation reduced abundance of Chironomid larvae, non-Chironomid Diptera, and Amphipods. The predation effect on Total Invertebrate dry mass was 2x higher in disced than in control areas.Invertebrate production also was measured in habitats denuded by foraging greater snow geese (Anser caerulescens atlantica) at Prime Hook National Wildlife Refuge. Chironomid larvae were 2 -6x more abundant in vegetated habitats than in areas where geese had foraged intensively, but exclosure data showed little effect of shorebird predation on invertebrate abundance. These results suggest that high goose populations can reduce waterbird food availability, and that shorebird use of invertebrates in denuded habitats is low.Mean true metabolizable energy (TME) of moist-soil seeds and invertebrates in blue-winged teal (Anas discors) ranged from -0.18 - 3.47 kcal / g. Correction of means for fiber concentration eliminated negative values, thereby enhancing their practical value.Potential duck use-days predicted using TME and seed production data were about 2x higher for disced than for control areas at Back Bay. Magnitude of the discing effect on duck use-days was largely insensitive to different estimates of seed nutritional value, although substantial variation in absolute measures of potential carrying capacity occurred. Discing positively influenced invertebrate abundance, and quantity and quality of moist-soil seeds produced, and should be considered a viable habitat management approach for both shorebirds and waterfowl.Ph. D.
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Magar, Shirish M. "Fermentation characteristics and nutritional value of ensiled deep pit caged layer waste and corn forage". Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80059.
Testo completoAbstract (sommario):
Deep-pit caged layer waste which had accumulated for about 2-yr was collected from beneath hens housed on wire mesh cages, was mixed with chopped corn forage and ensiled in 2 kg cardboard containers double lined with polyethylene bags and sealed to study fermentation characteristics and microbial analyses. Proportions of corn forage and caged layer waste, wet basis, were 100:0, 80:20, 70:30, 60:40, 50:50 and 40:60. Corn forage and caged layer waste in ratios of 100:0, 70:30, 60:40 and 50:50 mixtures, were ensiled in 210 liter metal drums doubled lined with polyethylene bags, to study fermentation characteristics, microbial analyses, chemical composition and to conduct a metabolism trial. For both types of silos the pH of the ensiled mixtures increased (P<.01) as level of waste increased. Lactic acid was higher (P<.01) for waste containing silages, compared to corn silage. Total coliforms, fecal coliforms, salmonella, shigella and proteus were decreased or eliminated by ensiling. Dry matter, crude protein, and ash increased (P<.01) with waste levels.
In a sheep metabolism trial, 30 wethers were fed diets consisting of the five silages in large silos, also, corn silage with sufficient soybean meal added to increase the crude protein content to that of 70:30 silage was used as a fifth diet.
Digestibility of dry matter and organic matter was higher (P<.01) for the corn silage diet, compared to the corn forage-waste silage diets, but the differences were small for organic matter. Within corn forage-waste silages a linear decrease (P<.05) was recorded in dry matter digestibility as caged layer waste increased. Apparent digestibility of dry matter, crude protein, organic matter, neutral detergent fiber (NDF), and acid detergent fiber (ADF) was higher (P<.01) for corn silage supplemented with soybean meal, compared with 70:30 corn forage-waste silage diet. Higher (P<.01) N utilization was obtained for sheep fed the corn silage diet, compared with those fed the waste treated silages. No difference (P<.05) in N retention was recorded when sheep were fed 70:30 corn forage-waste silage diet or corn silage supplemented with soybean meal.Master of Science
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Udomkun, Patchimaporn [Verfasser]. "Increasing nutritional value of papaya (Carica papaya L.) by optimizing pretreatment and drying parameters / Patchimaporn Udomkun". Aachen : Shaker, 2015. http://d-nb.info/1075437016/34.
Testo completo
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Ribeiro, J. E. M. M. (Jeronimo Ernesto Meneses Machado). "Growth, development and nutritional value of Amaranthus tricolor L. as affected by salinity and harvesting procedure". Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53746.
Testo completoAbstract (sommario):
Thesis (MScAgric)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Low crop productivity in arid and semi-arid regions is a problem caused by water stress as well as associated high levels of soil and water salinity. An increased demand for salt tolerant crops is experienced in these regions. Amaranth is a glycophyte and C4 dicotyledonous crop, well adapted to arid and semi-arid regions. Previous studies on the physiological response of salt-stressed amaranths have indicated that this crop is salt tolerant. As vegetable, amaranths can be harvested by uprooting and by topping. The most common harvesting method is by topping, allowing repeated harvesting. When harvested by topping, the cutting height is an important parameter that may be manipulated to optimise growth rates. In this study, plants were exposed to different salt stress levels and harvesting procedures while yield and quality of Amaranthus tricolor were investigated. Nutrient solutions at four different electrical conducti vi ty (EC) levels were used to fertigate the plants. At high EC levels (4 mS cm-l and 8 mS cm-lj, the length and diameter of main stems, internode lengths, stem weights as well as root weights were reduced, especially with a longer growth period. However, the shoot: root ratio and leaf protein yields increased and flowering was delayed. The best leaf yield was obtained where plants were fertigated at an EC of 4 mS cm-l for 45 days. The cutting height did not affect leaf yield, growth rates and leaf protein yield in plants fertigated at EC levels of 1, 2 and 4 mS cm-l. At an EC of 8 mS cm-l, the growth rate recovered to a value similar to that of plants fertigated with an EC of 2 mS cmonly where plants were topped at 25%. With this less destructive cutting height (topped at 25%), leaf yields, growth rates and ·leaf calcium and protein yields at an EC of 8 mS cm" were superior to that of plants topped at 50%. In plants topped at 25%, the recovered growth rates at EC 8 mS cm-l was probably due to more photosynthetic active tissue left after cuttings, resulting in the accumulation of compatible solutes for osmotic adjustment.
AFRIKAANSE OPSOMMING: Die invloed van soutstremmings en oesprosedures op die groei, ontwikkeling en blaarkwaliteit van Amaranthus trico~or L. Lae produksie van gewasse in ariede en semi-ariede gebiede is 'n probleem wat veroorsaak word deur watertekorte asook geassosieerde hoë peile van grondverbrakking en soute in water. 'n Verhoogde vraag na soutverdraagsame gewasse word in hierdie gebiede ervaar. Amaranthus is 'n glikofiet en dikotiele C4 gewas wat goed in ariede en semi-ariede streke aangepas is. Vorige ondersoeke oor die fisiologiese reaksie van Amaranthus op soutstremmings het daarop gedui dat die gewas soutverdraagsaam is. As groentegewas word dit ge-oes deur dit uit te trek of deur dit gereeld te top. Waar dit getop word is die oes-tophoogte 'n belangrike parameter wat gemanipuleer kan word om die groeitempo te optimaliseer. In hierdie ondersoek is plante aan verskillende peile van soutstremmings en oesprosedures blootgestel terwyl die opbrengs en kwaliteit van Amaranthus tricolor ondersoek is. Voedingsoplossings is teen vier elektriese geleidingspeile (EC) gebruik om plante te voedsproei. Teen hoë EC peile (4 mS cm-l en 8 mS cm-l ), het lengtes en die deursnit van hoofstamme, internode lengtes, stam massas en wortelmassas afgeneem, veral met lang groeiperiodes. Die opbrengs het egter bogroei:wortel verhouding en toegeneem terwyl blomvorming blaarproteien vertraag is. Die beste blaar opbrengs is na 45 dae verkry waar plante teen 'n EC van 4 mS cm-l gevoedsproei is. Oes-tophoogte het nie blaar opbrengs, groeitempo of blaar protei en opbrengs beïnvloed met EC waardes in voedingsoplossings van 1, 2 en 4 mS cm-l nie. Met' n EC van 8 mS cm-l het die groeitempo herstel tot 'n vlak, gelykwaardig aan wat by 'n EC van 2 mS cm-l verkry is, slegs waar teen 25% tophoogtes ge-oes is. Met hierdie minder destruktiewe oesmetode (oes-tophoogte 25%), was blaar opbrengs, groei tempo en blaar kalsium en -proteien opbrengste by 'n EC van 8 mS cm-l betekenisvol beter as waar die oes-topdiepte 50% was. Plante wat met 25% topdieptes ge-oes is se herstel in groetempo teen EC 8 mS cm-1 was waarskynlik te danke aan meer fotosinteties aktiewe materiaal wat na oes op plante gelaat is. Dit kon tot die akkumulasie van oplosbare stowwe en osmotiese aanpassings aanleiding gegee het.
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Alfaia, Cristina Maria Riscado Pereira Mateus. "Contribution to the study of lipid composition and nutritional value of intramuscular fat in ruminant meats". Doctoral thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2009. http://hdl.handle.net/10400.5/1157.
Testo completoAbstract (sommario):
Tese de Doutoramento em Ciência e Tecnologia AnimalContribuição para o estudo da composição lipídica e do valor nutricional da gordura intramuscular na carne de ruminantes - A composição em ácidos gordos e o ácido linoleico conjugado (CLA) são temas actuais de grande interesse, com particular relevância para a qualidade da carne e saúde humana. As carnes de ruminantes têm sido consideradas alimentos pouco saudáveis, principalmente devido à sua fracção lipídica com elevada concentração em ácidos gordos saturados. Contudo, as gorduras edíveis dos ruminantes são a principal fonte natural de isómeros CLA, sendo os isómeros bioactivos (c9,t11 e t10,c12) associados a propriedades potencialmente benéficas para a saúde humana. Em Portugal, a informação científica disponível para apoiar a qualidade e a reputação da carne bovina de raças autóctones criadas segundo as especificações de Denominação de Origem Protegida (DOP) continua restrita. Para além disso, os dados disponíveis não permitem ter uma percepção global de como distintos factores influenciam a composição da carne, desde a sua produção até ao consumo. Neste contexto, a nossa investigação foi desenvolvida estudando o efeito dos regimes alimentares dos animais (pastagem×concentrado), processamento tecnológico da carne após o abate (irradiação) e tratamentos térmicos (fervura, microondas e grelhagem), no perfil lipídico, especialmente nos isómeros do CLA, e no valor nutricional de carne de ruminantes. Foram seleccionadas e caracterizadas 4 carnes tradicionais DOP (Carnalentejana, Mertolenga, Barrosã e Arouquesa). Os resultados sugerem que a gordura intramuscular das carnes de novilho relativamente às de vitela, apresentam menor valor nutricional ao longo do ano, devido ao sistema de produção semi-extensivo utilizado nos novilhos. Por sua vez, a Carnalentejana-DOP apresenta uma qualidade nutricional superior comparativamente à carne de vaca de produção intensiva. No sentido de avaliar em detalhe o efeito de diferentes regimes alimentares no valor nutricional dos lípidos da carne, bem como a sua utilidade como discriminantes químicos da origem da carne, realizou-se um ensaio controlado. Os dados obtidos reforçam os resultados anteriores que sugeriam que a carne de animais de pastoreio apresenta melhor qualidade nutricional (teores mais elevados de n-3 PUFA e CLA) do que a carne de animais alimentados a concentrado. Este facto traduz os efeitos benéficos da pastagem no perfil de ácidos gordos da carne. Relativamente às alterações na composição da gordura intramuscular, resultantes do efeito de processamentos seguintes ao abate, a irradiação, uma tecnologia prospectiva para a conservação das carnes, não promoveu modificações significativas. Os tratamentos térmicos, frequentemente utilizados em culinária, induziram um impacto moderado no perfil dos ácidos gordos, como consequência das perdas de humidade e concentração da gordura. Em resumo, a composição lipídica da gordura intramuscular das carnes de bovino DOP estudadas apresenta um valor nutricional acrescentado para os consumidores, considerando os valores de n-3 PUFA, CLA (total e do isómero c9,t11) e da razão n-6/n-3, contribuindo para a sua diferenciação no mercado.
RESUMO - Contribuição para o estudo da composição lipídica e do valor nutricional da gordura intramuscular na carne de ruminantes - A composição em ácidos gordos e o ácido linoleico conjugado (CLA) são temas actuais de grande interesse, com particular relevância para a qualidade da carne e saúde humana. As carnes de ruminantes têm sido consideradas alimentos pouco saudáveis, principalmente devido à sua fracção lipídica com elevada concentração em ácidos gordos saturados. Contudo, as gorduras edíveis dos ruminantes são a principal fonte natural de isómeros CLA, sendo os isómeros bioactivos (c9,t11 e t10,c12) associados a propriedades potencialmente benéficas para a saúde humana. Em Portugal, a informação científica disponível para apoiar a qualidade e a reputação da carne bovina de raças autóctones criadas segundo as especificações de Denominação de Origem Protegida (DOP) continua restrita. Para além disso, os dados disponíveis não permitem ter uma percepção global de como distintos factores influenciam a composição da carne, desde a sua produção até ao consumo. Neste contexto, a nossa investigação foi desenvolvida estudando o efeito dos regimes alimentares dos animais (pastagem×concentrado), processamento tecnológico da carne após o abate (irradiação) e tratamentos térmicos (fervura, microondas e grelhagem), no perfil lipídico, especialmente nos isómeros do CLA, e no valor nutricional de carne de ruminantes. Foram seleccionadas e caracterizadas 4 carnes tradicionais DOP (Carnalentejana, Mertolenga, Barrosã e Arouquesa). Os resultados sugerem que a gordura intramuscular das carnes de novilho relativamente às de vitela, apresentam menor valor nutricional ao longo do ano, devido ao sistema de produção semi-extensivo utilizado nos novilhos. Por sua vez, a Carnalentejana-DOP apresenta uma qualidade nutricional superior comparativamente à carne de vaca de produção intensiva. No sentido de avaliar em detalhe o efeito de diferentes regimes alimentares no valor nutricional dos lípidos da carne, bem como a sua utilidade como discriminantes químicos da origem da carne, realizou-se um ensaio controlado. Os dados obtidos reforçam os resultados anteriores que sugeriam que a carne de animais de pastoreio apresenta melhor qualidade nutricional (teores mais elevados de n-3 PUFA e CLA) do que a carne de animais alimentados a concentrado. Este facto traduz os efeitos benéficos da pastagem no perfil de ácidos gordos da carne. Relativamente às alterações na composição da gordura intramuscular, resultantes do efeito de processamentos seguintes ao abate, a irradiação, uma tecnologia prospectiva para a conservação das carnes, não promoveu modificações significativas. Os tratamentos térmicos, frequentemente utilizados em culinária, induziram um impacto moderado no perfil dos ácidos gordos, como consequência das perdas de humidade e concentração da gordura. Em resumo, a composição lipídica da gordura intramuscular das carnes de bovino DOP estudadas apresenta um valor nutricional acrescentado para os consumidores, considerando os valores de n-3 PUFA, CLA (total e do isómero c9,t11) e da razão n-6/n-3, contribuindo para a sua diferenciação no mercado.
This work was co-financed by Centro de Investigação Interdisciplinar em Sanidade Animal (Project CIISA/52.Carne-Bioactivos) da Faculdade de Medicina Veterinária da Universidade Técnica de Lisboa and Fundação para a Ciência e a Tecnologia (POCTI/CVT/2002/44750) and Ministério da Agricultura (AGRO/2003/512).
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Rojo, Poveda Olga. "Valorisation of Compounds with High Nutritional Value from Cocoa By-Products as Food Ingredients and Additives". Doctoral thesis, Universite Libre de Bruxelles, 2021. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/322988.
Testo completoAbstract (sommario):
This doctoral thesis was conducted in the framework of a co-supervised PhD between the Department of Agriculture, Forestry and Food Sciences of the University of Turin and the Unit of Pharmacognosy, Bioanalysis and Drug Discovery of the Faculty of Pharmacy at the Université libre de Bruxelles. The present manuscript was conceived as a thesis of articles and is composed of 9 different scientific publications. The general introduction of the work was issued from a published narrative review, while the result and discussion part is composed by eight chapters based on different scientific articles issued from the PhD project. The cocoa bean shell (CBS) is the external tegument that covers the cocoa bean, and is one of the major by-products in cocoa industry. It is normally discarded or underutilized, which could result in economical and environmental issues. However, CBS represents a notable source of polyphenols and methylxanthines (theobromine and caffeine) which can give it different biofunctionalities such as antioxidant and antidiabetic properties, among others. It also contains high amounts of dietary fiber (about 50% w/w), minerals, vitamins, and proteins. CBS has low-fat content, and interesting cocoa-aroma compounds. All this could make CBS useful as a food ingredient, and source of biofunctional compounds. The first part of the experimental work of this thesis is devoted to the chemical characterization of CBS and the establishment of its polyphenolic and volatile organic compound (aroma) profiles. The utilization of such profiles, determined by both complete characterization methods and screening methods, was also proposed for authentication purposes of CBS depending on its geographical origin and variety. In a second step, the utilization of CBS as a low-cost food ingredient for functional food production was envisaged. CBS-based beverages and biscuits were proposed as model foods. The influence of the CBS addition to the model foods was evaluated from both technological and nutritional points of view. Changes on the physicochemical characteristics of the model foods were assessed as well as their content in compounds of interest and potential biofunctionalities. Moreover, these studies served also to evaluate the effect of the different food matrices on the bioaccessibility and intestinal permeability of the bioactive compounds contained in CBS. In the third and last part of this work, a different utility was given to the study of the cocoa by-product. The antimicrobial potential of CBS was assessed against different bacterial and fungal strains and a metabolomic strategy was applied in order to individualize the putative active compounds against the Streptococcus mutans proliferation. This work was a contribution for the valorization of a high add-value product such as the CBS, and a step towards a zero-waste cocoa industry within the frame of sustainable circular economy.Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie)
info:eu-repo/semantics/nonPublished
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Lane, Hillary Anne. "Variation in the nutritional value of Atlantic herring (Clupea harengus) from the Bay of Fundy, Canada". View electronic thesis (PDF), 2009. http://dl.uncw.edu/etd/2009-1/laneh/hillarylane.pdf.
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Alhadhrami, Ghaleb Ali. "Effect of preservatives and maturity on the nutritional value of alfalfa hay for lactating dairy cows". Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185343.
Testo completoAbstract (sommario):
Urea was applied uniformly inside alfalfa hay bales at baling or on top of bales subjected to rain and weather damage. Hay temperature, color, mold retardation and chemical composition were measured. Also, 24 lactating cows were used to test acceptability of the urea-treated hays. Cows were blocked for 14 d pre-treatment milk production and randomly assigned to one of six treated hays for 3 wk (4 cows/group). Cows were then reassigned at random to another hay for an additional 3 wk. Addition of 1% or more urea to high moisture alfalfa hay resulted in higher nutritional quality through reducing bale temperatures, non-enzymatic browning, and moldiness, compared to high moisture untreated hay. Urea treatment of high moisture hay decreased ADF and NDF content, while increasing digestibility of their fiber components. Urea treated hays were readily eaten by cows with no significant differences (P>.05) between treatments in DM intake, milk production, milk composition, or DM, ADF, and NDF digestion coefficients. Five types of alfalfa hay varying in % ADF were fed to 40 lactating cows. Cows were divided into 10 groups of 4 each based on 14-d pre-treatment milk. Each hay was mixed in TMR diets with 50 or 65% concentrate. In vivo and in situ trials were conducted to determine DM, ADF and NDF digestion. Results indicated that DMI, 3.5% FCM, cows body weight, body score, rectal temperature, and milk composition except milk fat were not affected by type of hay or level of concentrate. Milk fat was affected by level of concentrate (P<.16) while milk production was affected by type of hay (P<.01). Dry matter digestion coefficients for the complete rations showed no change with increased ADF in hay. Large decreases were noted in in situ DM, ADF, and NDF digestion as hay ADF increased. In another experiment, 32 mid to late lactation cows were used in a 41 d production trial. Cows were fed 2 levels of concentrate (25 vs. 50%) with alfalfa hay. Data indicated that DMI, milk yield, 3.5% FCM, milk composition, and other parameters did not differ between treatments. This might be due to the lack of response to higher concentrate level.
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Šottníková-Zajacová, Ivana. "Dietary strategies to improve the nutritional value of pork while maintaining a high sensory and technological quality /". Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17819.
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Zingbagba, Mark. "Three essays on Upstream and Downstream Disruptions along Nutritional High-value Food Supply Chains in Emerging Countries". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSES029/document.
Testo completoAbstract (sommario):
Cette thèse propose trois essais sur les perturbations tout au long de la chaîne de distribution des produits alimentaires à haute valeur nutritionnelle. Elle contribue à notre compréhension des menaces liées à la réalisation des objectifs de sécurité alimentaire dans les pays émergents. Contribuant à l'analyse économique de la chaîne de distribution et des questions agricoles, la thèse est fondée sur différents éléments théoriques relatifs à la chaîne de valeur, la croissance du marché, la transmission des prix et met en œuvre des techniques d'économétrie appliquée (économétrie des données de panel, économétrie des séries temporelles) à partir de base de données originales. L'objectif est d'analyser les sources et l'ampleur des perturbations dans la chaîne de distribution des produits à haute valeur nutritionnelle.La première partie de la thèse analyse les perturbations sur les marchés des produits alimentaires à haute valeur non-transformés et moins transformés. Le Chapitre 2 examine les perturbations en amont et en aval de la chaîne de distribution de ces produits. Le Chapitre 3 étend l’analyse du Chapitre 2 en prenant en compte les perturbations relatives aux produits ayant subi un niveau de transformation élevé. Dans les deux chapitres, les perturbations sont analysées en termes de changement de prix et de quantité, à la fois en amont et en aval. Le changement de quantité est considéré comme une perturbation préliminaire alors que celui de prix est secondaire. Utilisant le marché de São Paulo comme sujet d'étude, le Chapitre 4 analyse les effets du prix du diesel sur les différents segments de la chaîne de distribution des produits alimentaires à haute valeur nutritionnelle. Un modèle à correction d’erreur (MCE) qui prend en considération les effets des prix entre les différents produits est estimé pour vérifier si les chocs provenant du prix du diesel sont plus élevés en amont qu'en aval. Ce chapitre est analytiquement fondé sur la théorie de la transmission des prix.Les résultats des Chapitres 2 et 3 montrent que les désastres climatiques sont des sources dominantes de perturbation de la chaîne de distribution des produits alimentaires à haute valeur nutritionnelle. Leur effet est négatif pour tous les produits analysés, bien que l'ampleur de perturbation varie d’un produit à l’autre. Les résultats du modèle à correction d’erreur (MCE) du Chapitre 4 montrent que les effets du prix du diesel sur les prix des produits alimentaires à haute valeur nutritionnelle sont positifs et significatifs, alors que les effets en aval sont plus élevés que ceux en amont. Les résultats de la thèse ont des implications importantes pour le développement et la mise en œuvre des politiques d’alimentation dans les pays émergents. Le Chapitre 1, introduction générale, justifie l'étude des différences entre l'ampleur de perturbation en amont et celle en aval, et situe la thèse dans les littératures existantes. Une conclusion générale est proposée en Chapitre 5 avec des propositions pour de futurs travaux de rechercheThis dissertation presents three essays on disruptions along nutritional high-value food supply chains in emerging countries. It extends our understanding of threats to the attainment of food security in emerging countries. With a contribution to agricultural economics, the dissertation relies on value chain, market growth and price transmission theories and applies both panel data and time series econometric techniques to analyse the sources and magnitudes of the disruption of nutritional high-value food chains.The first part of the dissertation examines disruptions in unprocessed and minimally processed nutritional high-value food markets. Chapter 2 examines upstream and downstream disruptions along these food chains. Chapter 3 extends the analysis in Chapter 2 by assessing how disruptions change when nutritional high-value foods are highly processed. For each of the two chapters, disruptions are studied in terms of changes in upstream and downstream quantities and prices, with the disruption of quantity considered primary while that of prices is secondary.Using the São Paulo food market as a case study, Chapter 4 analyses the effect of diesel price shocks on different segments of the nutritional high-value food supply chain. A Vector Error Correction Model (VECM) that takes into account upstream and downstream cross-price effects is estimated to ascertain if diesel price shocks are higher downstream based on price transmission theory.The results of Chapters 2 and 3 show that climatological disasters are the most dominant source of disruption of nutritional high-value food supply chains and the direction of impact is negative for all foods under study. The magnitude of disruption, however, varies by food. From the VECM results in Chapter 4, we see that the price of diesel has a positive and significant effect on food prices, while the effects downstream are lower than those upstream. These results have significant implications for the design and implementation of food policies in emerging countries.As a general introduction, Chapter 1 justifies the need to study upstream and downstream differences in the magnitude of supply chain disruption, by situating the dissertation in the existing supply chain and food price transmission literature. Chapter 5 concludes the study and offers suggestions for future research
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Guerreiro, Olinda Rosa Fragoso das Neves. "Inclusion of Cistus ladanifer in ruminant diets : an approach to improve the nutritional value of edible fats". Doctoral thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/15786.
Testo completoAbstract (sommario):
Tese de Doutoramento em Ciências Veterinárias, na especialidade de Produção AnimalCistus ladanifer is a shrub quite abundant in Mediterranean countries, that when fed to lambs has been associated with changes in rumen biohydrogenation (BH), increasing t11-18:1 concentration in abomasal digesta and meat. The thesis main motivation was to further knowledge regarding C. ladanifer plant and to explore its utilization in nutritional strategies to ruminal BH modulation. In the first two experiments, seasonal variation of C. ladanifer aerial parts, with two ages, was characterized for chemical composition, including proximate composition and total phenols and condensed tannins (CT) contents, for in vitro digestibility, antioxidant activity and fatty acid (FA) profile. Cistus ladanifer was considered a nutritionally unbalanced feed, however, it may be used in ruminant nutrition, but only associated with other feeding resources to complement its nutritional imbalances. In third experiment, C. ladanifer fractions effects were tested on in vitro ruminal BH. Condensed tannins fraction was the most active on ruminal BH modulation, leading to a higher t11-18:1 accumulation and higher disappearance of substrate polyunsaturated FA. Therefore, we intended to determine which CT amount can optimize t11-18:1 ruminal synthesis. However, all CT fraction levels led to a depression of microbial growth without effects on ruminal BH. Last experiment was designed to explore effect of two levels of C. ladanifer CT (1.25% and 2.5%) and two ways of CT supply (C. ladanifer aerial parts and C. ladanifer CT extract) on lamb growth performance, carcass composition, meat quality and FA composition of lamb fat. The highest amount of C. ladanifer aerial part (2.5% of CT) had detrimental effects on growth performance, whereas, C. ladanifer CT extract inclusion in diet (1.25% of CT) led to the highest t11-18:1 increase in fat. So, we can conclude that C. ladanifer CT extract may be a good approach to improve the nutritional value of the ruminant edible fats.
RESUMO - Inclusão de Cistus ladanifer na dieta de ruminantes: uma abordagem para melhorar o valor nutricional das gorduras edíveis - As gorduras edíveis dos ruminantes têm sido associadas ao aumento do risco de doenças cardiovasculares, devido ao seu elevado conteúdo em ácidos gordos saturados, quantidades variáveis de ácidos gordos trans e baixo conteúdo de ácidos gordos polinsaturados. Este perfil de ácidos gordos (AG) resulta da bioidrogenação (BH) que os ácidos gordos polinsaturados da dieta sofrem no rúmen. Contudo, as gorduras edíveis dos ruminantes são naturalmente ricas em isómeros conjugados do ácido linoleico (CLA – conjugated linoleic acid), particularmente no isómero c9,t11-18:2, também designado por ácido ruménico. Diversos estudos in vitro e com modelos animais demonstraram que o c9,t11-18:2 possui atividades biológicas, como anti-inflamatória e anticarcinogénica. A manipulação da BH ruminal tem mostrado ser uma via para melhorar o valor nutricional das gorduras dos ruminantes, através do aumento da quantidade de ácidos gordos polinsaturados da dieta que escapam do rúmen sem sofrer alterações e do aumento da acumulação nos tecidos, e dos produtos dos intermediários da BH com efeitos benéficos, como CLA e do t11-18:1 (ácido vacénico), que é o principal precursor do c9,t11-18:2 nos tecidos. A inclusão de Cistus ladanifer L., um arbusto muito abundante na região Mediterrânea, em dietas à base de luzerna desidratada suplementada com 6% de óleos vegetais aumentou o t11-18:1 na digesta abomasal e na gordura intramuscular. Cistus ladanifer é rica em metabolitos secundários, que são compostos que não estão diretamente envolvidos nos processos de crescimentos, desenvolvimento e reprodução da planta, mas que contribuem para a adaptação e sobrevivência da planta. Contudo, a informação sobre a composição química da C. ladanifer é muito escassa, e não é claro qual a fração de C. ladanifer que possa ser responsável pela modulação da BH. A principal motivação desta tese foi aprofundar o conhecimento acerca da planta de C. ladanifer, e explorar a sua utilização em estratégias nutricionais para modular a BH ruminal. Nos dois primeiros ensaios, a variação sazonal das partes aéreas de C. ladanifer, com duas idades, foi caraterizada para a composição química, incluindo a composição proximal e o conteúdo em fenóis totais e taninos condensados (TC), para a digestibilidade in vitro, atividade antioxidante e perfil de AG. A parte aérea de C. ladanifer apresentou baixos teores de proteína, moderado conteúdo de constituintes parietais e baixa digestibilidade in vitro. Também foram encontrados na parte aérea da planta elevados teores em fenóis totais e TC, tendo estes aumentado durante o verão. A Cistus ladanifer é rica em AG saturados (73-82% do total de AG), e foram detetados pela primeira vez em arbustos dois AG de cadeia ramificada (iso-19:0 e iso-21:0), cujo conteúdo aumentou no verão e outono. Cistus ladanifer foi considerada como um alimento nutricionalmente desequilibrado, com teores elevados de fenóis totais e de TC. Contudo, pode ser utilizado na nutrição de ruminantes, mas apenas associado com outros recursos alimentares que complementem os seus desequilíbrios nutricionais. No terceiro ensaio, o efeito de cinco frações de C. ladanifer, ricas em metabolitos secundários, foi testado sobre a BH ruminal in vitro. Apesar de várias frações de C. ladanifer terem induzido alterações no perfil de AG, a fração de TC foi a fração mais ativa na modulação da BH ruminal, levando a uma maior acumulação de t11-18:1 e maior desaparecimento dos ácidos gordos polinsaturados do substrato. Após estes resultados pretendeu-se determinar a quantidade de TC de C. ladanifer que pode otimizar a síntese ruminal de t11-18:1. Contudo, quando testámos níveis crescentes de TC (entre 1,5 e 6% de TC, correspondendo ao valor máximo a mesma dose usada no ensaio anterior), todos os níveis de TC levaram a uma diminuição dos AG ramificados e dos dimetil acetais o que sugere uma redução do crescimento microbiano, sendo o efeito sobre a BH limitado. A BH do c9,c12,c15-18:3 sofreu uma ligeira redução com o aumento dos níveis de TC, sem efeito na produção de t11-18:1. Face aos resultados obtidos nos ensaios anteriores, o último ensaio foi delineado para explorar o efeito de dois níveis de TC de C. ladanifer (1.25% e 2.5%) e duas formas de fornecimento (parte aérea de C. ladanifer e extrato de TC de C. ladanifer) no desempenho produtivo, composição da carcaça, qualidade da carne e composição de AG da gordura de borregos. A incorporação dos níveis mais elevados de TC (2.5%) levou a efeitos prejudiciais no desempenho produtivo dos animais, especialmente com a inclusão da parte aérea de C. ladanifer, sem efeitos benéficos na composição de AG da gordura intramuscular e subcutânea. A inclusão de extrato de TC de C. ladanifer (1.25% de TC) na dieta levou ao aumento de t11-18:1 na gordura intramuscular e subcutânea, contudo, não afetou a concentração de c9,t11-18:2. Com esta tese podemos concluir que o extrato de TC de C. ladanifer pode ser uma boa abordagem para melhorar o valor nutricional das gorduras edíveis dos ruminantes.
N/A
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Mavimbela, David Thele. "The nutritional value of broiler litter as a feed source for sheep during periods of feed shortage". Thesis, Pretoria : [s.n.], 1999. http://upetd.up.ac.za/thesis/available/etd-12152006-153846.
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Jasson, Timothy Ivan. "Effects of compost tea extract on growth, nutritional value, soil quality of Hypoxis hemerocallidea and Siphonochilus aethiopicus". Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2791.
Testo completoAbstract (sommario):
Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2017.The exact responses to the concentration of compost tea extract and methods of irrigation application were not previously measured on Hypoxis hemerocallidea and Siphonochilus aethiopicus. Commercial exploitation, habitat loss and degradation, overharvesting, and enhancement of their medicinal properties, have led to this investigation and the need to replenish both these valuable plant species. This is crucial for plant survival, especially in the wild and for use of the traditional medicinal plants. Hypoxis hemerocallidea and Siphonochilus aethiopicus, known as star flower and wild ginger respectively continue to decline, due to overharvesting from their natural habitat. Both these species have tremendous traditional medicinal value among localized African people. To enhance their commercial cultivation, compost tea extracts, in the following ratios (no catalyst added (control1); T 1000:1, T750:1, T500:1, and T250:1L) were applied in equal dosages to determine an optimal compost tea extract ratio. The experiment was conducted in a temperature controlled greenhouse. Mushroom compost (500 g, per brew) was used for all extracts. Brewing was done with no catalyst added (Control 1), and 24 hours later another brew was done with catalyst added, weekly for 20 weeks. The Control treatment received water only. Both species were slow growing and comparatively, the Hypoxis plants responded faster than the Siphonochilus plants. In this investigation, plant growth parameters such as plant height, number of leaves, leaf width, leaf length and leaf colour, were measured and evaluated. Despite the plants positive response to the mushroom compost tea extracts, across all the above plant growth parameters, no significant differences were noted between the treatments during the twenty-week application period. Leaf chlorophyll content peaked in week 11 of the hypoxis plants and was the highest in week 14 of the Siphonochilus plants with no significant interaction between weeks vs. treatment over the twenty-week experiment. The chlorophyll readings indicate that both species increased their chlorophyll production over time. Although the total wet leaf length, root length, corm diameter, leaf weight, corm weight and root weight of Hypoxis were non-significant between treatments, T500:1 total wet weight was significantly higher when compared to the rest of the treatments. The total dry weight analysis of hypoxis was non-significant. Control Calcium level was significantly lower between the control and the treatments of the Hypoxis total dry leaf nutrient analysis. The Hypoxis dried roots nutrient analysis was non-significant across treatments.
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Guadagnin, Matteo. "Nutritional value of canola expellers produced "on farm" by cold extraction of oil used as bio fuel". Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3422576.
Testo completoAbstract (sommario):
General aim of this thesis was to study canola expellers (CE) extracted by cold pressing in a small plant (on farm) and to evaluate the validity to use this by-product in ruminant feeding. The thesis includes the results of four experimental contributes: the first one aimed to evaluate the stability of CE at different times and temperatures of storage in order to determine if the conditions usually found in the farms, especially during the hot season, can result in changes in fatty acids profile and in some oxidative parameters. Results found that under different temperatures (12, 24, and 36°C) and times of storage (10, 20, and 30 d), CE maintained a good oxidative stability, as evidenced by low peroxide values (< 10 mEq/kg fat) in all samples collected, by negative response for Kreis test and by low changes in fatty acids profile. From these results it could be hypothesized that the storage of these by-products did not change the characteristics of the lipid fraction. In the second contribute in vitro gas production (GP) values obtained from the incubation of CE, whole soybean seed (WSS) and soybean meal (SBM) were compared, incubating feed samples with two media containing N-rich buffer or N-free buffer, in order to compare the effect of the availability of feed as unique protein source. Results of the experiment showed that CE is an easily degradable protein source. In the first hours of incubation with limiting N availability, higher gas production was recorded compared to the two soybeans. On this basis, CE could be interesting in diets at low protein content, currently suggested in order to reduce nitrogen excretion. No toxic effects on the microbial yield were observed during the fermentation of the three different feeds. The third contribute compared four diets formulated for beef cattle, based on corn silage and containing WSS or CE as protein sources at two different inclusion levels, in order to obtain 15 and 11 % CP of DM in the diets. Diets were tested using Rusitec fermenter. Compared to WSS, CE provided greater NDF degradability (P < 0.01), produced less acetate and propionate (P < 0.001) but more butyrate and branched-chain VFA. The total VFA production was similar for the two protein sources. With regard to nitrogen balance, CE showed greater 15N enrichment in the non-ammonia N (P < 0.01) and nominally lower values of microbial N derived from ammonia compared to WSS (P = 0.06). At high inclusion level, the 15N enrichments for ammonia N, non-ammonia N and total bacteria N were also greater than observed at low inclusion levels (P < 0.001). In conclusion, the two feeds showed different fermentation patterns. The manipulation of dietary protein level seemed to lead primarily to a variation of bypass protein, without effects on the synthesis of microbial N.
In the fourth contribute the same diets tested in Rusitec fermenter (third contribute) were evaluated using RF system (Ankom Technology, Macedon, NY, USA) in order to evaluate their gas production kinetics. Results showed that both NDFd and TDMd values were greater (P<0.05) for CE diets compared to WSS, confirming the results obtained with Rusitec and as expected were lower (P=0.04) for L compared to H diets. Compared to WSS, CE inclusion in the diets increased the rate of GP (P<0.05;) but did not affect the total amount of GP. The reduction of CP level in the diets from 15 to 11% decreased the rate of GP without effects on total GP. Ammonia content increased (P<0.01), as expected, with the level of dietary CP. In conclusion, when diets with low CE levels are used, the inclusion of rapeseed cake in replacement to soybean seeds could improve the rate of degradation during the first hours of fermentation. In general CE obtained by cold extraction on farm could be an interesting feed in ruminant feeding with economical and environmental benefits.Obiettivo generale di questa tesi è stato quello di studiare e valutare il panello di colza (CE) estratto a freddo in impianti aziendali di piccole dimensioni per un potenziale utilizzo nell'alimentazione dei ruminanti. Nella tesi sono riportati i risultati di quattro prove sperimentali: nel primo contributo è stata valutata la stabilità della frazione lipidica del CE a temperature diverse e per diversi periodi di tempo al fine di valutare se la conservazione in condizioni anche particolari (durante la stagione estiva) in azienda, possa modificare il profilo degli acidi grassi e alcuni parametri di ossidazione lipidica. I risultati hanno evidenziato che a diverse temperature (12, 24, e 36°C) e tempi di stoccaggio (10, 20, e 30 d), CE ha mantenuto una buona stabilità ossidativa, come evidenziato dai bassi valori del numero di perossidi (<10 mEqO2/kg grasso), dal test di Kreis sempre negativo, e dalle scarse variazioni del contenuto di acidi grassi. Da questi risultati preliminari si può ipotizzare che lo stoccaggio aziendale per i panelli sottoprodotti ottenuti dal colza in azienda, non determina grosse variazioni della componente lipidica. Nel secondo contributo sono state valutate, in vitro, le produzioni di gas prodotti da campioni di CE e da semi di soia integrale incubando i questi alimenti con due differenti media: uno ricco in a N e uno senza N in modo da confrontare lâandamento delle fermentazioni quando lâunica fonte di N risulta lâalimento. I risultati hanno evidenziato che CE è una fonte proteica rapidamente degradabile; in caso di diete ipoproteiche come quelle suggerite per ridurre lâescrezione azotata, la sua inclusione potrebbe favorire l'attività microbica ruminale. Non sono sati rilevati effetti tossici sulla microflora ruminale durante la fermentazione dei due alimenti. Nel terzo contributo sono state confrontate in vitro quattro diete per bovini da carne a base di silomais con 2 livelli di inclusione di CE e WSS, in modo da ottenere un livello di proteina grezza paria al 15% e allâ11% PG sulla sostanza secca. In questa prova è stato utilizzato il sistema semicontinuo di fermentazione Rusitec. Le diete contenenti CE hanno mostrato una maggior (P <0.01) degradabilità dell'NDF, e prodotto meno (P <0.01) acetato e propionato ma più butirrato e acidi grassi ramificati. La produzione totale di AGV non è risultato diversa tra le due fonti proteiche. Il bilancio dellâN ha mostrato un maggior quantità (P <0.01) di arricchimento in15N nellâazoto non ammoniacale e valori tendenzialmente (P = 0.06) inferiori di N microbico derivato dall'uso di ammoniaca rispetto alle diete con inclusione di WSS. Nelle diete ad alto livello di inclusione i valori di arricchimento in 15N delle varie frazioni azotate sono risultati, come atteso, più alti (P <0.01) rispetto a quelle a basso livello di inclusione. In conclusione i due supplementi hanno mostrato andamenti fermentativi molto diversi. I due diversi livelli di inclusione hanno influito principalmente sulla disponibilità di proteina by pass senza effetti sulla sintesi microbica. Nel quarto contributo sono state testate, con la tecnica della gas production, le stesse quattro diete usate nel precedente esperimento. Eâ stato utilizzato il sistema RF Ankom® per testare la cinetica della produzione di gas nel corso della fermentazione. I risultati hanno mostrato che sia i valori di degradabilità dell'NDF che della SS sono stati maggiori (P < 0.05) per le diete contenenti CE rispetto a quelle con WSS e, come atteso, sono risultati inferiori nella diete a basso livello di inclusione delle due fonti proteiche. Le diete CE sono state caratterizzate da una produzione oraria di gas superiore (P < 0.05) in, ma non è variata la quantità totale di gas prodotto. La riduzione del livello di CP da 15 all'11% SS ha diminuito il tasso di produzione di gas ma non la quantità totale. Il contenuto di ammoniaca nel liquido ruminale al termine dellâincubazione è risultato più alto (P < 0.001) nelle diete ad alto livello di inclusione. Concludendo possiamo affermare che con diete a basso livello di proteina, l'uso di CE in sostituzione alla soia, può migliorare la velocità di degradazione durante le prime ore di fermentazione. In generale, il panello di colza ottenuto per estrazione a freddo in azienda potrebbe essere un alimento interessante nell'alimentazione dei ruminanti con effetti favorevoli sia dal punto di vista economico che ambientale
47
Bvenura, Callistus. "Wild vegetables of the Eastern Cape of South Africa: the nutritional value and domestication of solanum nigrum l". Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1015514.
Testo completoAbstract (sommario):
An ethnobotanical survey was conducted in Alice and Willowvale in the Nkonkobe and Mbashe municipalities of the Eastern Cape Province, South Africa to identify and document wild vegetables growing in the areas. The survey documented 22 vegetable species belonging to 12 different families. The Amaryllidaceae, Amaranthaceae, Apiaceae, Asteraceae, Caryophyllaceae, Chenopodiaceae, Convolvulaceae, Cruciferae, Cucurbitaceaea, Euphorbiaceae, Tiliaceae, Solanaceae, Polygonaceae and Urticaceae were the families that were recorded. The species were Tulbaghia violacea Harv., Amaranthus blitoides S., Amaranthus blitum L., Amaranthus hybridus L., Centella coriacea Nannfd., Bidens pilosa L, Cotula heterocarpa DC., Sonchus oleraceus L., Galinsoga parviflora Cav., Taraxacum officinale Weber, Hypochaeris radicata L., Stellaria media L., Chenopodium album L., Chenopodium murale L., Ipomoea batatas L., Sisymbrium thellungii O. Schulz, Cucurbita pepo L., Rumex crispus L., Acalypha virginica L., Nicandra physalodes L., Physalis peruviana L., Solanum nigrum L., Urtica urens L. and Corchorus olitorius L. About 27 % of the wild vegetables were native to South Africa and about 45 % were also used as medicinal plants in the areas. Sun drying was the most common method of preserving the wild vegetables for the off season months. This study also revealed that, men and the younger generation knew less about wild vegetables than the women. The study also revealed a loss of knowledge of wild vegetables and their use by the rural dwellers who are more in favour of the exotic types such as spinach and cabbage.
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Walker, Keitirele Patricia. "Productivity of four fodder tree species, their nutritional value and potential role in ruminant production in Eastern Botswana". Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1421.
Testo completoAbstract (sommario):
Thesis (PhD (Forest and Wood Science))—University of Stellenbosch, 2007.Sustainable livestock production in semi-arid Botswana could be improved through tree planting on-farm to provide much needed protein and shade. Such action can be encouraged if the growth, productivity, nutritional value of trees and their contribution to mass gain of livestock are known.. A study at Malotwana investigated two indigenous species, Acacia galpinii and Faidherbia albida, and two exotic species, Leucaena diversifolia and L. leucocephala, at three spacings in a randomised complete block design replicated five times. The three spacings represented 400, 317 and 241 trees per hectare. The study was conducted over 6.5 years. Indigenous trees were sampled biennially and exotics annually to evaluate crown width, height, stem diameter, stem number and stem volume index. Complete plant harvesting of exotic trees at 2.5, 4.5 and 6.5 years evaluated agroforestry production. Leaves from all four species and pods of exotic species were analysed for chemical composition. Two groups of eight lambs were balanced for mass at selection for an on-farm feeding trial. Browse from exotic trees, comprising a 2:1 ratio of pods to leaves, was fed at 30% as supplement to hay to one group whose mean mass was contrasted with that of the control group fed sorghum bran at 30%. A. galpinii was a promising species, adaptable to planting away from its origin. Its crown width ranged from 5.86 m in high density plots to 6.08 m at low density and was significantly different among stands (p = 0.0406) at 6.5 years. Diameter at breast height (dbh) was significantly different among stands aged 6.5 years (p = 0.0003) and ranged between 10.38 cm at high density to 12.48 cm in low density plots, demonstrating a capacity to provide both shade and poles on-farm. At 4.5 years, F. albida attained a mean height of 4.5 m and 4.5 cm in dbh but suffered 67% mortality during a severe drought. Annual fodder production of 0.647 and 0.996 metric tonnes ha-1 for leaves and pods of L. diversifolia and 1.237 and 1.431 for L. leucocephala was recorded in years of average rainfall. Yields of 0.3 and 0.59 metric tonnes ha-1 were recorded for both species in the driest year. Equally good agroforestry production was obtained from both low and high density stands suggesting that low density plantings, which foster higher plant survival and reduce disease incidence, are best suited to the semi-arid conditions of Botswana. The crude protein of leaves ranged between 16.26 (L. diversifolia) and 25.25% (F. albida). They were highly digestible with more than twice the calcium content livestock require. Crude protein and digestibility measures were significantly different among leaves and varied significantly at different spacings (p<0.0001). Pods of the exotic species contained significantly more protein than the leaves (p<0.0001). Lambs supplemented with browse gained 102.33 g per animal per day while the control group gained 83.95 g. There were significant differences between groups during growth (p<0.05). Growing of A. galpinii, complemented with L. diversifolia and L. leucocephala, can supply short and long term feed, and greatly enhance livestock production while diversifying farm feed sources
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Abazinge, Michael D. A. "Studies of methods of preserving and enhancing fermentation, nutritional value and palatability of seafood waste for feeding ruminants". Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49972.
Testo completo
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Hamilton, Jeffrey Muir. "Arugula Crop Production in Arid and Semi-Arid Regions: Nutritional Value, Postharvest Quality, and Sustainability in Controlled Environments". Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/195968.
Testo completoAbstract (sommario):
Plant responses to abiotic stress are neither singular nor linear. The research represented within this dissertation was intended to evaluate selected biochemical and physiological responses in two Arugulas (Images 1-5), to agronomic interventions designed to mitigate extreme environmental abiotic factors, characteristic of arid agricultural production regions. Plant stress responses were investigated under field conditions and within controlled environments (CE), during the course of a preliminary trial and three independent studies, all four directly related. The preliminary trial evaluated harvest and postharvest nutritional content (i.e., antioxidants) of two Arugulas, Eruca sativa (L.) Cav. ssp. sativa (P. Mill.) and Diplotaxis tenuifolia (L.) DC cv. Sylvetta; grown under field conditions in the semi-arid upper Sonoran Desert. In this trial, we defined baseline harvest and postharvest antioxidant values for the Arugulas, cultivated in a semi-arid environment. The initial study, conducted within a CE utilizing a water recycling system, evaluated changes in the nutritional value of three specialty leafy cruciferous vegetables: D. tenuifolia, E. sativa and Lepidium sativum; when subjected to increasing salinity levels in the nutrient solution. It was concluded that, when specific Crucifers are irrigated with moderately high levels of salinity, neither harvest nor postharvest nutritional values are compromised. The second study, investigated the response of a suite of plant physiological parameters (e.g., yield and photosynthetic rate) in the three Crucifers to salinity, within the CE. This research provided guideline salinity values where yields did not decline, and encourages growers to consider water resources compromised by salinity and nutrient solution recycling. During the third study, the influence of environmental conditions on the nutritional content in leafy vegetables, prevalent immediately before harvest, was investigated; by subjecting plants to reduced sunlight treatments and early irrigation termination. We observed that, modulating light intensity late in the season, and early irrigation termination strategies, modify the nutritional content of leafy vegetables; and potentially the subsequent postharvest shelf life. Collectively evaluated, this research suggests that simple agronomic interventions are valuable, yet practicable, tools that can enhance the nutritional content of specialty vegetables, in arid regions: be that intervention an imposed controlled-stress, utilizing nutrient recycling systems within a CE, or basic light-reduction and irrigation termination strategies within conventional fields systems.