Dissertations / Theses on the topic 'Cowpea – Nutrition'

Thesis (MScAgric) -- University of Stellenbosch, 2003.
ENGLISH ABSTRACT: Cowpeas are produced under low and irregular rainfall in most of arid and semi-arid areas of sub-Saharan Africa. Growth and yield are therefore reduced due to the occurrence of water stress during the growing season. Knowledge of the responses and adaptive mechanisms of cowpeas to water stress may help to improve the management practices for these areas. Therefore, three glasshouse experiments were conducted at Welgevallen Experimental Farm of the University of Stellenbosch to test the responses of two cowpea cultivars to water stress. In the first experiment, physiological responses were used to identify those physiological parameters, which can be used to distinguish between drought tolerant and susceptible cowpea cultivars. In the second experiment, some of the identified physiological parameters together with some morphological growth responses, yield and grain protein content of the same two cowpea cultivars were used to identify which is the more tolerant cultivar. Tn the third experiment, the hypothesis that increased phosphorus supply may improve the tolerance of cowpea plants to water stress and their ability of recover from the stress was tested. The results showed that water stress affected water relations, morphological growth parameters, yield and grain protein content, but increasing P supply reduced the effect of water stress and promoted more rapid recovery after re-watering. Water relations were affected by water stress because it reduced relative water content, which resulted in reduced water potential and increased leaf diffusive resistance and proline accumulation. Morphological growth responses and yields were affected because water stress reduced the leaf area, which resulted in reduced biomass production and seed yield. Lower leaf area under water stress was the result of the reduced number of leaves and leaf expansion rate, but the number of leaves was the most important parameter. Reduced seed yield was due to reduced number of pods. The responses of the two cultivars tested were different. AB Wit, which performed better under well-watered conditions was more affected by water stress due to its larger leaf area that resulted in excessive water loss by transpiration. ACH14 was more drought tolerant than AB Wit due to a combination of a more rapid stomatal closure and proline accumulation, which induced osmotic adjustment, and which in tum helped to maintain higher water potentials. The increased P supply reduced the effect of the water stress. High-P level plants showed higher root growth, which resulted in more water uptake and larger leaf area during the water stress period, and after re-watering these plants recovered more rapidly. The more rapid recovery from stress was the result of enhanced root growth and leaf expansion rate and most probably due to increased water uptake. High-P level plants also showed more rapid leaf appearance and plant growth at earlier stages compared to the low-P level plants.
AFRIKAANSE OPSOMMING: Akkerbone word onder toestande van lae en wisselvallige reenval in baie ariede en semi-ariede gebiede van Afrika verbou. In hierdie gebiede word groei en produksie dikwels beperk deur water tekorte gedurende die groei seisoen. Kennis van reaksies en aanpassingsmeganismes van akkerbone teenoor water tekorte mag dus help om produksietegnieke in bogenoemde gebiede te verbeter. Om hierdie rede is drie glashuiseksperimente onder gekontroleerde toestande op die Welgevallen Proefplaas van die Universiteit van Stellenbosch uitgevoer. In die eerste eksperiment is fisiologiese reaksies van twee cultivars gebruik om eienskappe te identifiseer wat gebruik kan word om tussen droogteweerstandbiedende en droogte gevoelige cultivars te onderskei. In die tweede eksperiment is sommige van die geidentifiseerde eienskappe asook morfologiese groei, opbrengs en kwaliteitsreaksies van dieselfde twee cultivars gebruik om die meer droogte weerstandbiedende cultivar te identifiseer. In die derde eksperiment is die hipotese dat P-bemesting die droogteweerstandbiedendheid teen en herstelvermoe na droogte kan verbeter, getoets. Die resultate toon dat water tekorte beide plantwaterverhoudings, morfologiese eienskappe asook opbrengs en proteieninhoud beinvloed, maar dat hoe P-peile die invloed van water tekorte verminder en herstelverrnoe na die droogte verbeter. Plant-waterverhoudings is bemvloed omdat water tekorte relatiewe waterinhoud van plante verlaag wat aanleiding gee tot verlaagde plantwaterpotensiale, verhoogde huidmondjie weerstand en 'n toename in prolien inhoud. Morfologiese eienskappe en opbrengs is benadeel weens 'n veri aging in blaaroppervlakte wat fotosintetiese vermoe en gevolglik ook biomassaproduksie en saad opbrengs benadeel. Verlaagde blaaroppervlakte tydens water tekorte was hoofsaaklik die gevolg van 'n vermindering in aantal blare, terwyl verlaagde saadopbrengs grootliks die resultaat van 'n vermindering in aantal peule was. Die cultivar AB Wit wat die hoogste opbrengs onder gunstige groeitoestande gelewer het, is die meeste bemvloed deur water tekorte omdat die welige blaargroei van hierdie cultivar, luukse waterverbruik en groter transpirasie verliese veroorsaak het. Die cultivar ACH 14 daarteenoor het waterverliese beperk deurdat die huidmondjies vinniger gesluit het en verhoogde prolien-inhoude, osmotiese aanpassings veroorsaak het. Dit het gehelp om waterpotensiale instand te hou. Hierdie cultivar was gevolglik meer droogte weerstandbiedend as AB Wit. Hoe vlakke van P-bemesting het die effek van water tekorte verminder weens verbeterde wortelgroei. Dit het wateropname gedurende en na die peri ode van water stremming verbeter sodat plante vinniger herstel het na die droe periode. Plante wat by hoe P-peile gegroei is het ook 'n verhoogde blaarverskyningstempo en 'n toename in groei tydens die vroee ontwikkelingstadiums getoon.

The objective of this study was (1) quantify N₂ fixation in sole and mixed cropped cowpea, (2) To access nutrient assimilation by component species in the cropping system, and (3) to determine the effects of cropping system on C metabolites. At harvest the dry mass of both cowpea and maize were highest in sole crops. There was a significant difference in % nitrogen of maize and cowpea plants from the different cropping systems. Total nitrogen content was highest in sole cropped maize and cowpea plants with sole cowpea fixing the most N₂. δ¹⁵N values were lower for the shoots of symbiotic cowpea compared to the maize. Root δ¹⁵N values were also generally lower in cowpea than in maize. The %N derived from fixation (Ndfa) was similar for sole, intra and intercropped cowpea. However the amount of N fixed was significantly greater in sole cowpea compared to intra- and intercropped cowpea. When nutrient uptake and assimilation was assessed in the cropping system, it was found that mineral elements such as Ca, Mg, Cu, Zn and B occurred in significantly greater concentrations in the N₂-fixing legume compared to the cereal partner. However the concentration of soluble sugars and starch remained the same for both shoot and roots of cowpea and maize plants in the cropping system.

Pasta was produced from soft wheat supplemented with cowpea. Acid detergent fiber values increased from 0.4% in the soft wheat pasta (SWP) to 1.1% in the 30% cowpea pasta (CP). Cowpea supplementation provided an increase in total and available lysine from 42 to 113% and 39 to 117%, respectively. Chemical scores for preschool children increased from 56 in the SWP to 89 in the 30% CP. For school children the 20% CP provided a score of 102. The in vitro protein digestibility (IVPD) of cowpea was lower than that of soft wheat; as a result cowpea reduced the IVPD of SWP from 84% to a value of 78% for the 30% CP. The protein content of SWP was 10.9% while the CP ranged from 11.3 to 14.2%. Considering IVPD values, SWP contained 9.2% digestible protein and CP from 9.2 to 11.1%. After cooking, only the 30% CP displayed trypsin inhibitor activity. Upon visual examination, cowpea improved the color of SP making it comparable to the durum semolina control (DSC) but lacking its translucency. A sensory panel reported no difference in acceptability among treatments. Cooked weights were similar to the SWP, except with 30% replacement when a decrease was observed. CP, after 10 minutes of cooking demonstrated reduced loss as supplementation was increased. After 20 minutes all treatments had similar cooking loss compared to the SP. All treatments displayed cooking quality results significantly different from the DSC.

Thesis (M. S.)--Michigan State University. Dept. of Food Science and Human Nutrition, 2006.
Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references (p. 67-70). Also issued in print.

Protein-energy malnutrition (PEM) among children remains a huge burden in Africa. Due to poverty, such children rely on the same starchy staples, such as sorghum, consumed in the household, as both their source of energy and protein. However, sorghum has a low protein quality, particularly with respect to the indispensable amino acid lysine and also protein digestibility. Local pulses such as cowpea are important vehicles to address PEM. Biscuits are favoured as means of fortification because they are palatable, nutrient-dense, in ready-to-eat form and have a long shelf-life. Therefore, the objectives of this study were to develop and evaluate the effect of fortifying whole grain sorghum with whole grain cowpea on the nutritional quality, instrumental, sensory characteristics and consumer evaluation of the biscuits. Composite biscuits were produced from two types of whole grain sorghums, white tan-plant, non-tannin (WTP) and red non-tannin (RNT) composited with whole grain cowpea at 60:40 ratio. These were compared with commercial economic wheat biscuits. Sorghum-cowpea biscuits had 50-60% higher protein content than 100% sorghum biscuits but were the same as that of wheat biscuits. The mineral content of sorghum-cowpea biscuits was 27-29% and 37% higher than that of 100% sorghum and wheat biscuits, respectively. The pepsin in-vitro protein digestibility (IVPD) of the sorghum-cowpea biscuits was 71-81% higher than that of 100% biscuits due to inclusion of the more digestible cowpea globulin proteins. However, the average pepsin IVPD of the sorghum and sorghum-cowpea biscuits was 211% and 76% lower than that of wheat biscuits, respectively. There was no trypsin inhibitor activity in the sorghum-cowpea biscuits due to the dilution of the trypsin inhibitors in cowpea. The total phenolic content of the sorghum-cowpea biscuits was 30-45% and 70% higher than that of 100% sorghum and wheat biscuits, respectively. Sorghum-cowpea biscuits were stronger than 100% sorghum biscuits due to water soluble-globulin proteins from cowpea. Correspondence analysis (CA) revealed that 64% of the variation in terms of texture and flavour of the biscuits was due to type of cereal (sorghum or wheat) and 23% was due to the presence of cowpea in biscuits, respectively. Standard wheat biscuits were the most liked. However, using cluster analysis, individual overall liking of consumers varied and four different clusters of consumers with similar liking of the biscuits were identified. Two clusters with substantial percentage of consumers (41%) liked the sorghum-cowpea biscuits. These findings suggest that sorghum-cowpea composite biscuits could well serve as an acceptable high quality protein-rich complementary food to alleviate PEM, and generate income for smallholder farmers in rural areas of Africa where sorghum and cowpea are produced and consumed as staples.
Dissertation (MSc)--University of Pretoria, 2013.
lk2014
Food Science
MSc
Unrestricted

Abstract The aim of this study was to evaluate plant growth, grain yield and symbiotic N contribution by 32 cowpea genotypes, at Taung in South Africa. The data from a 2-year field study conducted in 2005 and 2006 showed that genotypes Fahari, Pan 311 and Glenda exhibited the highest dry matter yield and N contribution as they produced 2.9-, 2.7- and 3.5-fold more dry matter than cv. ITH98-46 and yielded 2.7-, 2.2- and 3.2-fold more N than cultivar ITH98-46 from IITA. Except for Benpila, all the 32 cowpea genotypes derived between 52.0 and 80.9% of their N nutrition from symbiotic fixation in 2005, with IT82D-889, Botswana White, IT93K-2045-29 and Ngonji exhibiting the highest %Ndfa values. The genotype Fahari showed the highest amount N-fixed (182 kg N-fixed/ha), followed by Pan 311, Glenda, TVu11424 and Mamlaka which contributed 160, 146, 130 and 125 kg N/ha, respectively. Genotypes Pan 311, Fahari and Glenda were among those that produced highest grain yield in 2005 and except for CH14 and IT86S-2246 (which produced 131 kg N/ha each), Fahari, Glenda and Pan 311, were again the highest in symbiotic N contribution (112, 106 and 105 kg N/ha, respectively). Grain yield was similarly high in Glenda, Pan 311 and Fahari (3.3, 3.1 and 2.9 t/ha, respectively) in 2006. In general, these data show that genotypes that fixed more N also produced more biomass and grain yield and are therefore, the best candidates for inclusion in cropping systems as biofertilizers.

Thesis (Ph.D.) --University of Limpopo, 2012
A series of experiments were carried out to evaluate the feeding values of forage sorghum (Sorghum sudanense), cowpea (Vigna ungiculata), lablab (Lablab purpureus) and mucuna (Mucuna pruriens) hays for Pedi goat production in Limpopo Province, South Africa. The first study determined nutrient composition and tannin contents of the forages. The experimental design was a completely randomised design with four treatments: forage sorghum, cowpea, lablab and mucuna hays. All the legume species had higher (P<0.05) protein contents than sorghum hay, ranging from 18 to 22 %. Within the legume species, cowpea hay had a higher (P<0.05) protein content than lablab and mucuna hays. Similarly, lablab hay had a higher (P<0.05) protein content than mucuna hay. Mucuna hay had a higher (P<0.05) concentration of both condensed tannins and hydrolysable tannins than cowpea, lablab and sorghum hays, while lablab hay had the highest (P<0.05) concentration of total polyphenols. The second study determined relative palatability indices of Pedi goats offered forage sorghum, cowpea, lablab and mucuna hays. Four male Pedi goats aged five months and weighing an average of 18 + 2 kg were used. The experimental design was a completely randomized design, with feeds (forage sorghum, cowpea, lablab and mucuna) as treatments and individual animals as replicates. Lablab and mucuna legumes had higher (P<0.05) intake and palatability indices than sorghum and cowpea hays. Palatability indices were positively and significantly (P<0.05) predicted from dry matter intakes of goats (r2 = 0.98). However, there were poor and non-significant (P>0.05) relationships between nutrient contents of the forages and their intake and palatability indices by goats. The third study determined diet intake, digestibility and live weight gain of seven months old Pedi goats fed a basal diet of forage sorghum supplemented with different amounts of cowpea, lablab or mucuna hays. The experimental design was a completely randomized design, with individual animals placed in digestibility crates as experimental units. This study was divided into a series of experiments due to lack of equipment to conduct the whole experiment in one session. A total of four experiments were conducted. Fifteen growing male Pedi goats were used in each experiment, with mean live weights of 15 + 4 kg, 18 + 2 kg, 17 + 3 kg and 20 + 4 kg for experiments 5.1, 5.2, 5.3 and 5.4, respectively. In each experiment, different goats were used. Experiments 5.1 to 5.3 involved cowpea, lablab and mucuna hays, respectively, while Experiment 5.4 compared the levels of supplementation for optimum intake from each of the first three experiments. Dry matter intakes of cowpea and lablab hay were optimised at 39 and 32 %, respectively, while that of mucuna hay increased with increasing levels of mucuna hay supplementation. Dry matter digestibilities of cowpea, lablab and mucuna hays increased with increasing levels of the respective forage supplementations. Cowpea and mucuna hay supplementations improved (P<0.05) final live weights and feed conversion ratios, while goats on lablab hay supplementation lost weight. At optimum intake, goats supplemented with mucuna hay had a better (P<0.05) feed conversion ratio than those supplemented with lablab and cowpea hays. The fourth study determined in vitro gas production of pure and mixtures of forage sorghum with cowpea, lablab and mucuna hays. Two experiments were conducted. In the first experiment (Experiment 6.1) the experimental design was a completely randomised design with four treatments (forage sorghum, cowpea, lablab and mucuna). The legume species of cowpea, lablab and mucuna hays produced more (P<0.05) gas than sorghum hay after 12 hours of incubation. Sorghum hay produced more (P<0.05) gas than cowpea, lablab and sorghum hays after 24, 48 and 72 hours of incubation. Sorghum hay dry matter intake by goats in the palatability trial was positively and significantly (P<0.05) predicted from gas production after 12 (r2 = 0.99), 24 (r2 = 0.97) and 48 (r2 = 0.93) hours of incubation. Cowpea hay, lablab hay and mucuna hay dry matter intakes by goats were poorly predicted from gas production after 12, 24, 48 and 72 hours of incubation. In the second experiment (Experiment 6.2), the experimental design was a completely randomised design with three treatments (mixtures at optimum intake): 1. FS61C39: A mixture of 61 % forage sorghum and 39 % cowpea, 2. FS68L32: A mixture of 68 % forage sorghum and 32 % lablab, 3. FS77M23: A mixture of 77 % forage sorghum and 23 % mucuna. There were no differences in gas production (P>0.05) across dietary mixtures after 12, 24, 48 and 72 hours of incubation. Dry matter intake by Pedi goats of sorghum hay mixed with cowpea at 39 % hay was positively and significantly (P<0.05) predicted from gas production of the mixtures after 24 hours (r2 = 1.0) of incubation. Dry matter intake from gas production from the same mixture was poorly predicted from gas production after 48 (r2 = 0.45) and 72 (r2 = 0.13) hours of incubation. Dry matter intake of sorghum hay by Pedi goats supplemented with lablab hay at 32 % was moderately predicted from gas production after 48 (r2 = 0.67) and 72 (r2 = 0.60) hours, but poorly predicted after 12 (r2 = 0.50), 24 (r2 = 0.53) hours of incubation. Dry matter intake of sorghum hay by Pedi goats supplemented with 23 % mucuna hay was positively predicted from gas production after 12 (r2 = 0.90) hours, but moderately predicted after 24 (r2 = 0.80), 48 (r2 = 0.72) and 72 (r2 = 0.83) hours of incubation. Dry matter digestibility of sorghum hay mixed with 23 % mucuna hay was positively and significantly (P<0.05) predicted from gas production after 24 (r2 = 1.0), 48 (r2 = 0.99) and 72 (r2 = 1.0) hours of incubation. Dry matter digestibility of sorghum hay mixed with 39 % cowpea hay was positively predicted from gas production after 48 (r2 = 0.95), moderately predicted after 24 and 72, and poorly predicted after 12 hours of incubation. Dry matter digestibility of sorghum hay mixed with 32 % lablab hay was positively predicted from gas production after 72 (r2 = 0.92) hours of incubation. The relationships between digestibility of the mixtures and gas production after 12, 24 and 48 hours of incubation were poor. The fifth study determined in sacco degradation of mixtures at optimum intake of forage sorghum mixed with cowpea, lablab or mucuna when incubated in goats. The ‘a’ values and dry matter losses in cowpea and lablab hays were higher (P < 0.05) than those of mucuna hay. Dry matter intake of sorghum hay mixed with lablab hay at 32 % was positively and strongly predicted from in sacco degradation after 12 (r2 = 0.90), 24 (r2 = 0.94), 48 (r2 = 0.96) and 72 (r2 = 0.97) hours of incubation. Dry matter intake of sorghum hay mixed with 39 % cowpea hay was poorly predicted from in sacco degradation after 12 (r2 = 0.25), 24 (r2 = 0.20), 48 (r2 = 0.11) and 72 (r2 = 0.08) hours of incubation. Dry matter intake of sorghum hay mixed with 23 % mucuna hay was positively and moderately predicted from in sacco degradation after 12 (r2 = 0.68) hours and 24 (r2 = 0.55) hours, but poorly predicted after 48 (r2 = 0.40) and 72 (r2 = 0.20) hours of incubation. vii It was concluded that cowpea, lablab and mucuna hays had higher protein contents and palatability indices than forage sorghum and therefore, have the potential of being utilised as protein supplements for goats on low quality roughages. Legume supplementation, in general, improved diet intake, digestibility, feed conversion ratio and live weight of goats, except for lablab hay supplementation. It was also noted that diet intake, digestibility and final live weights of the goats were optimised at different levels of forage supplementation. This may indicate that supplementation levels for optimum productivity will depend on the particular parameter in question. In vitro gas production and in sacco degradation techniques have the potential of predicting intake, digestibility and palatability indices of goats fed sorghum hay supplemented with cowpea, lablab or mucuna hays.

Thesis (DTech (Chemistry))--Cape Peninsula University of Technology, 2005
A 2-factorial experiment, involving 3 levels of phosphorus (0, 40, and 80 kg P.ha-I ) as main treatment and 4 cropping systems (mono crop, maize/cowpea inter-row, maize/cowpea intra-row, and maize/cowpea intra-hole cropping) as sub-treatment was conducted in the field for 2 consecutive years in 2003 and 2004 to assess i) the effects of exogenous P supply and cropping system on the concentrations of plant-available nutrients in the rhizosphere of cowpea and maize; ii) the effect of exogenous P supply on tissue concentrations of minerals in nodulated cowpea and maize in mixed plant cultures iii) the effects of exogenous P supply and cropping system on plant growth and N2 fixation, and iv) the effects of exogenous P supply and cropping system on phosphatase activity and microbial biomass in the rhizosphere of cowpea and maize. At harvest, it was found that applying 40 or 80 kg P.ha-I significantly increased cowpea grain yields by 59-65% in 2003 and 44-55% in 2004. With maize, the increases in grain yield were 2037% in 2003 and 48-55% in 2004 relative to zero-P control. In both cropping seasons, the number of pod-bearing peduncles per plant, the number of pods per plant, the number of seeds per pod, and seed yield per cowpea plant were significantly increased with the application of exogenous P. In contrast, these parameters were all significantly depressed by mixed culture relative to mono crop cowpea. Intercropping maize with cowpea produced higher total yields per unit land area than the sole crop counterpart.

Protein-energy malnutrition (PEM) is a major problem in sub–Saharan Africa, which is predominant in children and women. Poverty is the underlying cause. Children rely on cereal staples like sorghum for nutrient supply. However, sorghum is limiting on indispensable amino acid lysine and has poor protein digestibility, compromising its protein quality. Cowpeas are major subsistence crops in sub-Saharan Africa due to their tolerance to harsh climatic conditions and notable protein quality. Snacks are widely consumed by school-going children during break lunches and convenient, palatable, ready-to-eat and have long-shelf life. Therefore sorghum-cowpea snack blends have potential to address PEM. Hence, objectives of the study were to develop and evaluate the effects of compositing sorghum with cowpea on nutrient quality and sensory properties of snack blends. Ready-to-eat sorghum-cowpea expanded snacks were produced using a twin screw extruder. Snacks were made from 0, 25 and 50% ratios of wholegrain cowpea flour (Glenda variety) to commercial decorticated red non-tannin sorghum flour and 1% salt. The nutritional and sensory characteristics of snacks were investigated in terms of proximate and nutrient composition, protein digestibility, lysine content, mineral content and bioaccessibility and descriptive sensory analysis coupled with instrumental texture (breaking force) and colour analyses. Inclusion of cowpea significantly improved nutrient composition of the snacks. A 30 g packet of composite snacks would provide 4-5 g protein which is 15-31% of the protein daily requirement for school-age children. Cowpea inclusion significantly increased lysine by 97% of daily requirement for school-age children. The sorghum-cowpea blend snacks had some 16% improved in-vitro protein digestibility. Hence, the calculated Protein Digestibility Corrected Amino Acid Scores of the blend snacks was more than double that of the sorghum only snacks. Mineral contents of snacks were improved on cowpea inclusion. However, phytate content increased also, decreasing the bioaccessibility of the minerals. Conversely, inclusion of cowpea flour darkened the colour and increased dark specks in the snacks. Snack hardness was similarly rated by panellists and the instrumental texture analysis. Beany, cocoa, burnt, boiled and roasted nut flavours with metallic aftertaste were highly perceived in the 50:50 blend. Salt addition affected salty flavour only. Inclusion of cowpeas in extruded cereal snack formulations has the potential to address PEM in school-going children in sub-Saharan Africa because it substantially improves the protein content and quality of the snacks. Although inclusion of 50% cowpea gave the highest nutritional quality, it resulted in a beany flavour and metallic aftertaste. These may require masking through commercial flavouring for consumer acceptability.
Dissertation (MSc)--University of Pretoria, 2016.
Food Science
MSc
Unrestricted

Orientador: André Rodrigues dos Reis
Resumo: O selênio (Se) é um nutriente para humanos e animais e um elemento benéfico para as plantas, sua baixa concentração nos solos do Brasil pode gerar deficiência nos animais e humanos. O fitato é a principal forma de reserva de fósforo (P) encontrado nas sementes de plantas, sendo considerado um “anti-nutriente” por formar complexos não digeríveis com nutrientes como Fe, Ca e Zn. Desta forma, existe a necessidade de se buscar alternativas para aumentar os teores de Se e reduzir o teor de fitato nas partes comestíveis de cultivares modernos. O objetivo do trabalho foi avaliar doses e fonte ótimas de Se a serem aplicadas em condições brasileiras, bem como a influência do Se na produção e qualidade nutricional em 29 genótipos de feijão-caupi. Para isso, foram desenvolvidos dois experimentos a seguir: Experimento 1: Foi avaliada a eficiência da biofortificação agronômica utilizando 2 fontes de Se (selenato e selenito) e 7 doses de Se (0; 2,5; 5,0; 10,0; 20,0; 40,0 e 60 g ha-1) aplicados via solo, foi realizada analise de fitatos nos grãos. Experimento 2: Foi realizado um experimento para caracterizar a absorção e acúmulo de Se, teor de fitatos, açucares, proteínas de reversa e amino ácidos nos grãos de diferentes genótipos de feijão-caupi, nesse experimento, 29 genótipos foram avaliados na presença e ausência de Se (0 e 25 kg ha-1), cultivados até o final do ciclo para a obtenção dos grãos. No experimento 1, observou-se que a aplicação de selenato proporciona maiores concentrações d... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O melhoramento genÃtico convencional de feijÃo-caupi [Vigna unguiculata (L.) Walp] tem como proposta aperfeiÃoar suas propriedades agronÃmicas. Entretanto, a partir de uma preocupaÃÃo mundial, considerando alÃm das necessidades dos agricultores, empresÃrios e exportadores, tambÃm se busca desenvolver cultivares com maior qualidade nutricional para os consumidores. O objetivo geral deste trabalho foi analisar o efeito do melhoramento genÃtico convencional do feijÃo-caupi sobre os atributos nutricionais e propriedades funcionais de importÃncia industrial. Os atributos nutricionais foram avaliados inicialmente por meio da determinaÃÃo da composiÃÃo proximal e de minerais. As mÃdias (% base seca) dos valores de proteÃnas totais, lipÃdios, cinzas, fibra alimentar total e carboidratos digerÃveis foram 22,95; 1,60; 3,84; 17,80 e 53,87, respectivamente. Jà os teores de ferro e zinco foram em mÃdia 4,62 e 3,21 mg/100g de semente, respectivamente. Os genÃtipos com teor proteico acima de 25% apresentaram uma boa digestibilidade in vitro (cerca de 70%) e perfil de aminoÃcidos, inclusive os sulfurados, estando todos presentes em nÃveis acima do recomendado para crianÃas de 3 a 10 anos. Em comparaÃÃo com a soja, foram encontrados nÃveis baixos ou moderados de fatores tÃxicos e/ou antinutricionais nos genÃtipos com destaque em teor de proteÃna, ferro e zinco. Houve uma variaÃÃo no teor dos Ãcidos fenÃlicos (11,18 a 94,60 mg/g de semente), taninos (1,33 a 3,05 mg/g de semente), inibidores de tripsina (30,15 a 40,47 UI/mg de proteÃna), inibidores de quimotripsina (14,21 a 26,43 UI/mg de proteÃna) e lectinas (20.000 a 80.000 UH/Kg de semente). Ao se construir Ãndices de qualidade nutricional dos genÃtipos de feijÃo-caupi, verificou-se que os teores dos antinutrientes estudados podem modificar a classificaÃÃo dos mesmos. No entanto, quando os genÃtipos de feijÃo-caupi sÃo comparados com a soja, uma leguminosa amplamente consumida, percebe-se que esses fatores nÃo sÃo de grande relevÃncia, pois hà mÃtodos de inativaÃÃo e/ou remoÃÃo dos componentes indesejados. Propriedades funcionais promissoras foram encontradas para os genÃtipos avaliados, tais como capacidade de absorÃÃo de Ãgua e Ãleo, geleificaÃÃo e espumabilidade, as quais apontam para uma possÃvel aplicaÃÃo da farinha de feijÃo-caupi na indÃstria alimentÃcia. Baseando-se nos Ãndices de qualidade nutricional por meio das caracterÃsticas nutricionais e bioquÃmicas, os trÃs genÃtipos sugeridos para serem usados como parentais em programas de melhoramento genÃtico e produÃÃo de sementes sÃo: G17 (MNC02-682F-2-6), G03 (BRS ARACÃ) e G01 (BRS- JURUÃ).
Cowpea [Vigna unguiculata (L.) Walp] conventional breeding aims to improve its agricultural characteristics. However, there is a global concern that besides considering the needs of farmers, entrepreneurs and exporters, it is also necessary to develop cultivars with higher nutritional quality for consumers. The aim of this study was to evaluate the effects of conventional breeding of cowpeas upon their nutritional attributes and functional properties of industrial significance. The nutritional attributes were initially evaluated by determination of proximate and minerals composition. The means (% dry basis) of total proteins, lipids, ashes, total dietary fiber and digestible carbohydrates content were 22.95; 1.60; 3.84; 17.80 and 53.87, respectively. Mean values for iron and zinc contents were 4.62 and 3.21 mg/100g of seeds, respectively. Genotypes with protein content over 25% showed good in vitro digestibility (ca. 70%) and amino acid profile, including sulfur amino acids, all being in higher levels than the requirements for 3-10 years old children. The levels of toxic and/or antinutritional factors in the genotypes with better contents of protein, iron and zinc were low to moderate compared to those of soybeans. There were reasonable variations in phenolic acid contents (11.18 to 94.60 mg/g of seeds), tannin (1.33 to 3.05 mg/g of seeds), trypsin inhibitor (30.15 to 40.47 UI/mg protein), chymotrypsin inhibitor (14.21 to 26.43 UI/mg protein) and lectin (20,000 to 80,000UH/kg seeds). By using nutritional quality indexes of cowpea genotypes it was observed that the contents of antinutrients may change the ranking position. Nevertheless, when cowpea genotypes are compared to soybeans, it is observed that these factors are not so relevant considering that this legume seed is safely consumed by animals and humans since there are methods to inactivate or remove them. Promising functional properties were detected in the analyzed genotypes, such as water and oil absorption capacity, gelation and foaming properties. These properties point to a possible utilization of cowpea flour in the food industry. Based upon the nutritional quality indexes, we conclude that the top three genotypes suggested to be used as parentals in cowpea breeding programs are G17 (MNC02-682F-2-6), G03 (BRS-ARACÃ) and G01 (BRS-JURUÃ).

PEREIRA, R. F. Caracterização bioquímica, nutricional e funcional de genótipos elite de feijão-caupi [Vigna unguiculata (L.) Walp]. 2013. 79 f. Dissertação (Mestrado em Bioquímica) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2013.
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Cowpea [Vigna unguiculata (L.) Walp] conventional breeding aims to improve its agricultural characteristics. However, there is a global concern that besides considering the needs of farmers, entrepreneurs and exporters, it is also necessary to develop cultivars with higher nutritional quality for consumers. The aim of this study was to evaluate the effects of conventional breeding of cowpeas upon their nutritional attributes and functional properties of industrial significance. The nutritional attributes were initially evaluated by determination of proximate and minerals composition. The means (% dry basis) of total proteins, lipids, ashes, total dietary fiber and digestible carbohydrates content were 22.95; 1.60; 3.84; 17.80 and 53.87, respectively. Mean values for iron and zinc contents were 4.62 and 3.21 mg/100g of seeds, respectively. Genotypes with protein content over 25% showed good in vitro digestibility (ca. 70%) and amino acid profile, including sulfur amino acids, all being in higher levels than the requirements for 3-10 years old children. The levels of toxic and/or antinutritional factors in the genotypes with better contents of protein, iron and zinc were low to moderate compared to those of soybeans. There were reasonable variations in phenolic acid contents (11.18 to 94.60 mg/g of seeds), tannin (1.33 to 3.05 mg/g of seeds), trypsin inhibitor (30.15 to 40.47 UI/mg protein), chymotrypsin inhibitor (14.21 to 26.43 UI/mg protein) and lectin (20,000 to 80,000UH/kg seeds). By using nutritional quality indexes of cowpea genotypes it was observed that the contents of antinutrients may change the ranking position. Nevertheless, when cowpea genotypes are compared to soybeans, it is observed that these factors are not so relevant considering that this legume seed is safely consumed by animals and humans since there are methods to inactivate or remove them. Promising functional properties were detected in the analyzed genotypes, such as water and oil absorption capacity, gelation and foaming properties. These properties point to a possible utilization of cowpea flour in the food industry. Based upon the nutritional quality indexes, we conclude that the top three genotypes suggested to be used as parentals in cowpea breeding programs are G17 (MNC02-682F-2-6), G03 (BRS-ARACÊ) and G01 (BRS-JURUÁ).
O melhoramento genético convencional de feijão-caupi [Vigna unguiculata (L.) Walp] tem como proposta aperfeiçoar suas propriedades agronômicas. Entretanto, a partir de uma preocupação mundial, considerando além das necessidades dos agricultores, empresários e exportadores, também se busca desenvolver cultivares com maior qualidade nutricional para os consumidores. O objetivo geral deste trabalho foi analisar o efeito do melhoramento genético convencional do feijão-caupi sobre os atributos nutricionais e propriedades funcionais de importância industrial. Os atributos nutricionais foram avaliados inicialmente por meio da determinação da composição proximal e de minerais. As médias (% base seca) dos valores de proteínas totais, lipídios, cinzas, fibra alimentar total e carboidratos digeríveis foram 22,95; 1,60; 3,84; 17,80 e 53,87, respectivamente. Já os teores de ferro e zinco foram em média 4,62 e 3,21 mg/100g de semente, respectivamente. Os genótipos com teor proteico acima de 25% apresentaram uma boa digestibilidade in vitro (cerca de 70%) e perfil de aminoácidos, inclusive os sulfurados, estando todos presentes em níveis acima do recomendado para crianças de 3 a 10 anos. Em comparação com a soja, foram encontrados níveis baixos ou moderados de fatores tóxicos e/ou antinutricionais nos genótipos com destaque em teor de proteína, ferro e zinco. Houve uma variação no teor dos ácidos fenólicos (11,18 a 94,60 mg/g de semente), taninos (1,33 a 3,05 mg/g de semente), inibidores de tripsina (30,15 a 40,47 UI/mg de proteína), inibidores de quimotripsina (14,21 a 26,43 UI/mg de proteína) e lectinas (20.000 a 80.000 UH/Kg de semente). Ao se construir índices de qualidade nutricional dos genótipos de feijão-caupi, verificou-se que os teores dos antinutrientes estudados podem modificar a classificação dos mesmos. No entanto, quando os genótipos de feijão-caupi são comparados com a soja, uma leguminosa amplamente consumida, percebe-se que esses fatores não são de grande relevância, pois há métodos de inativação e/ou remoção dos componentes indesejados. Propriedades funcionais promissoras foram encontradas para os genótipos avaliados, tais como capacidade de absorção de água e óleo, geleificação e espumabilidade, as quais apontam para uma possível aplicação da farinha de feijão-caupi na indústria alimentícia. Baseando-se nos índices de qualidade nutricional por meio das características nutricionais e bioquímicas, os três genótipos sugeridos para serem usados como parentais em programas de melhoramento genético e produção de sementes são: G17 (MNC02-682F-2-6), G03 (BRS ARACÊ) e G01 (BRS- JURUÁ).

Thesis(M.Sc.(Agriculture Horticulture)) -- University of Limpopo, 2019
Innovative methods of preserving the quality of traditionally processed green leafy vegetables are underway in Africa. Improvement of processing and preservation methods of leafy vegetables is another way of overcoming perishability restrictions and guaranteeing continued quality food supply in rural areas. The objectives of this study were: to determine the effect of time-based oven-drying on (1) mineral composition, (2) proximate composition and (3) microbial profiling of cowpea (Vigna unguiculata). Separate experiments were conducted for raw and cooked cowpea leaves with four treatments, viz 0 (sun dried), 24, 48 and 72 hours of oven-drying, arranged in a randomised complete block design with 5 replications. In raw cowpea leaves, relative to control (sun-drying), oven-drying period 48hrs, significantly decreased Potassium (K), Manganese (Mn), and Sodium (Na) content in raw cowpea leaves by 6, 9 and 13%, respectively. Similarly, oven-drying period 72hrs significantly decreased Ca, Fe, Mg, Zn, P and S by 5, 11, 16, 18 and 57%, respectively. In cooked cowpea leaves, relative to control (sun-drying), oven-drying period 24hrs significantly increased Na by 18%. Similarly 48hrs oven-drying periods increased Fe and K by 6 and 8%, respectively. Similarly, oven-drying period 72hrs significantly increased Ca, Mg and Mn by 8, 8 and 3%, respectively. In contrast, oven-drying period 72hrs significantly reduced Zn, P and S by 16, 10 and 39%, respectively. Relative to control (sun-drying), oven-drying period 24hrs significantly increased fat by 46% in raw cowpea leaves, however oven-drying period 72hrs significantly decreased protein, moisture, ash, fibre and carbohydrate by 10, 29, 18, 0.5, and 7% respectively. In contrast, relative to control (sun-drying), 72hrs increased energy by 3%. In cooked cowpea leaves, relative to control (sun-drying), oven-drying period 24hrs significantly increased energy by 1%. In contrast, relative to control (sun-drying) 72hrs oven-drying period decreased energy by 1%. Similarly, ovendrying 72hrs significantly decreased protein, moisture, ash, fat, fibre and carbohydrate by 8, 14, 13, 19, 0.4 and 10% respectively. Relative to control (sun-drying), oven-drying periods 24hrs significantly increased Staphylococcus spp. in raw cowpea leaves by 6%, respectively. Relative to control (sun-drying) 72hrs oven-drying period significantly decreased Shigella spp. by 92%, respectively. In cooked leaves, relative to control (sundrying), 72hrs drying periods decreased both Shigella spp. and Staphylococcus spp. by 99 and 21%, respectively. Total coliforms unit of Salmonella spp, Escherichia coli, Pseudomonas spp, and Bacillus cereus were absent and/or at an undetectable level according to the Tempo Biomerieux system results. In conclusion, cooked leaves retained most essential mineral elements as compared to raw when subjected to 72hrs of oven-drying as there was an improvement in the concentration of Ca, Fe, K, Mg, Mn and Na. However, in both raw and cooked cowpea leaves proximate composition was negatively affected as there was a decrease in protein content. Oven-drying period of 24 hours can be used to minimize the loss of protein. Cooked cowpea leaves subjected to 72hrs of oven-drying had least total coliforms for both Shigella spp and Staphylococcus spp, therefore have potential to serve as an alternative to sun-drying to reduce microorganism causing spoilage in leafy vegetables. Drying raw cowpea leaves under oven-drying periods less than 72 hours should be avoided as it reduces the mineral concentration and increase microbial count of microorganisms responsible for spoilage.
National Research Foundation

The study aimed at determining the contribution of cowpeas to dietary diversity and food access, among women living in a peri-urban area of Gaborone called Gabane village in Botswana. Consuming a variety of food groups ensures adequate intake of nutrients for health. Diet diversity measures diet quality, food access and an indication of nutritious diets. Cowpeas are a nutritious vegetable which can contribute to diet diversity, diet quality and food access of many poor rural households who cannot afford to purchase a wide variety of nutritious food (ARC, 2006). Data was collected through administering a Cowpea consumption survey questionnaire which indicated that most of the households consume cowpeas which are essential to improve household food access, diet diversity and diet quality. A socio-demographic questionnaire was also used and it indicated an average number of household members of 6 people. The respondents were mainly the elderly people of 56 years and above with primary school education as the most achieved level of education. A Household Dietary Diversity Score (HDDS) questionnaire was contextualised for local foods consumed in Botswana. Focus group discussions were conducted to collect more data from women regarding their attitude, opinions and perceptions of consuming a variety of foods, cultivating and consuming cowpeas to ensure good health. The focus group results indicated that cowpeas were consumed by most families and 100% of adults and children consume cowpeas as leaves and seeds. Cereals were predominantly consumed by 95% of households, vitamin A rich fruits and vegetables by 52.5%, meat, poultry and fish by 42.5%. Vitamin A rich foods such as vegetables, fruits and organ meat were poorly consumed except green leafy vegetables which included cowpea leaves consumed by 52.5%. Meat, poultry and fish were consumed by 42.5%. Legumes, nuts, seeds and organ meat were also poorly consumed. vii Cowpeas grow well in Botswana, are Batswana’s cultural food, can improve nutritional intake and livelihoods through sold surplus profit. A diet diversity score of 2.9, well below the advised cut-off point of 4 was documented, indicating poor household dietary diversity and poor diet quality and food access.
Agricultural, Animal Health and Human Ecology
Thesis (M.A. (Human ecology) )

Thesis of Ph.D. in Animal Science
Nutritional valorization of cowpea (Vigna unguiculata) co-product for animal feeding The concept of circular economy is considered a sustainable principle for the reuse of underutilized agro-industrial co-products by shielding global markets against scarcity of resources and volatility of prices. Agro-industrial co-products are of low economic value as foods for human consumption but may have potential value as animal feedstuff, and in the Mediterranean production systems, agricultural co-products have been used as an important feedstuff during periods of shortage of forage. Another possible utilization of these compounds relies on its inclusion on compound feeds, especially in rabbit production. The Eurolegume project, in which this thesis is developed, evaluated cowpea (Vigna unguiculata), pea (Pisum sativum) and fava (Vicia faba) local genetic resources for the development of new varieties for food and feed. Management and valorization of residual biomass for animal feed were also evaluated in the project and created the opportunity to enrol on a PhD program and develop this thesis. Cowpea stover has been shown to be a feedstuff with high cell wall content (666 g kg-1 DM), moderate protein value (121 g kg-1 DM) and high lignin content (109 g kg-1 DM) which in turn influence in vitro digestibility values for rabbits (396 g kg-1 OM) and ruminants (603 g kg-1 OM) and in sacco degradability for ruminants (Chapter 1). The leaves of the cowpea stover showed to be the fraction with high nutritional value and its conservation is considered important. Based on these results the thesis advances in two lines of research to evaluate the potential of cowpea stover as animal feed: 1) potential use of cowpea stover treated/untreated with white-rot fungi for animal feeding and 2) conservation of the mixture’s treated/untreated cowpea stover and discarded apple by the ensilage process. In Chapter 2 we evaluated the effect of the incorporation of 0, 20 and 40 g kg-1 of untreated cowpea stover in compound feed on the coefficients of total tract apparent digestibility of organic matter, crude protein, neutral detergent fibre and gross energy of growing rabbits. Cowpea stover presented a good potential to be used in rabbit feeding as its inclusion in the experimental diets up to 40 g kg-1 did not affect growth performances. However, its inclusion showed to negatively influence protein digestibility values, indicating that its inclusion should be further evaluated so that these possible detrimental effects could be overcome. In this way, chemical or biological pre-treatment of cowpea stover should also be considered as they might improve the digestibility of this feedstuff. As white-rot fungi degrade lignin efficiently, due their extracellular enzymatic system and hyphal penetration power, its potential to improve the nutritive value of cowpea stover was studied. In Chapter 3 five strains of white-rot fungi (Ganoderma lucidum, Lentinula edodes, Pleurotus citrinopileatus, Pleurotus eryngii and Phlebia rufa) were tested on the pretreatment of cowpea stover for 22 and 45 days of incubation. In this study, P. citrinopileatus with 22 days of incubation presented the best results in the delignification (-46%) and increase in in vitro digestibility for rabbits (+30%) when compared to the control diet. This trial provided enough evidence to produced larger amounts of treated cowpea stover in order to increase the inclusion levels in rabbit´s diets. For this purpose, we formulated five diets containing 50 and 100 g kg-1 of treated cowpea stover and 50 and 100 g kg-1 untreated cowpea stover, and basal diet (Chapter 4). Animals fed diets with the treated cowpea stover showed a higher final live weight (+5,0%) and a reduction in blood cholesterol levels (-17%) than the ones fed diets with untreated cowpea stover. As cowpea stover is harvested at the same time that high amounts of discarded apple are normally available, the possibility to use mixtures of both co-products and its potential to be ensiled were evaluated. These silages could be an alternative feedstuff during feed shortage periods. Thus, a novel feedstuff, ensiled discarded apple (85%) and cowpea stover (15%) mixtures with two different ensiling periods (45 and 60 days) on nutritive value, fermentation quality and aerobic stability was evaluated (Chapter 5). The mixtures evaluated could be conserved by the ensiling process. Both silages, with 45 and 60 days of ensiling period, were stable presenting low pH values (≤ 4.0), no butyric acid and high aerobic stability (216h). However, the low residual water-soluble carbohydrate (WSC) concentrations of the resulting silages indicated that lactic acid additives should be used to control microbial fermentation to improve its nutritive value. Furthermore, as fungi treated cowpea stover was already evaluated in previous trials, in Chapter 6, we evaluated the preservation by the ensilage process of treated cowpea stover (15%) and discarded apple (85%) and the effect of the use of a commercial inoculant (Sil-All LV®). The treatment of cowpea stover, before ensilage, with P. citrinopileatus modified the chemical composition and in vitro digestibility, resulting in an increase of its nutritive value when compared with untreated cowpea stover. Silages, inoculated and noninoculated with Sil-All, were stable after 45 days of ensiling, presenting low pH values (≤ 4.2) and no butyric acid. Inoculated silage showed higher lactic acid and ethanol concentrations compared to non-inoculated silage. On the other hand, lower acetic acid was observed in the inoculated silage.
Valorização nutricional de co-produto de feijão-caupi (Vigna unguiculata) para alimentação animal O conceito de economia circular é considerado um princípio sustentável para a utilização de coprodutos agroindustriais, protegendo os mercados globais contra a escassez de recursos e a volatilidade dos preços. Co-produtos agroindustriais, em geral, são pouco utilizados na alimentação humana, mas podem apresentar potencial para uso na alimentação animal. Nos sistemas de produção do Mediterrâneo, co-produtos agrícolas são usados como uma importante fonte alimentar aos animais durante períodos de escassez de forragem. Ainda, sua incorporação nos alimentos compostos é usual, especialmente em dietas de coelhos. O projeto Eurolegume, no qual esta tese é desenvolvida, avaliou os recursos genéticos locais do feijão-frade (Vigna unguiculata), ervilha (Pisum sativum) e da fava (Vicia faba) para o desenvolvimento de novas variedades de grãos para alimentação humana. A gestão e valorização da biomassa residual para alimentação animal foi avaliada no projeto e criou a oportunidade de se inscrever no programa de doutorado e desenvolver esta tese. O restolho de feijão-frade tem se mostrado um alimento com alto conteúdo de parede celular (666 g kg-1 de MS), moderado teor de proteína (121 g kg-1 de MS) e alto teor de lignina (109 g kg-1 de MS) que por sua vez influencia valores de digestibilidade in vitro para coelhos (396 g kg-1 MO) e ruminantes (603 g kg-1 MO) e a degradabilidade in sacco para ruminantes (Capítulo 1). As folhas do restolho de feijão-frade são uma fração com alto valor nutricional e sua conservação é considerada importante. Com base nesses resultados, a tese avançou em duas linhas de pesquisa para avaliar o potencial do restolho de feijão-frade como alimento para animais, avaliando: 1) potencial uso de restolho de feijãofrade tratado ou não tratado com fungos da podridão-branca e 2) conservação de mistura de restolho de feijão-frade tratado ou não em associação com maçã descarte pelo processo de ensilagem. No Capítulo 2 avaliamos o efeito da incorporação de 0, 20 e 40 g kg-1 restolho de feijão-frade em alimento composto e o efeito no coeficiente de digestibilidade aparente da matéria orgânica, proteína bruta, fibra em detergente neutro e energia bruta de coelhos em crescimento. O restolho de feijão-frade apresentou um bom potencial para ser utilizada na alimentação de coelhos, uma vez que sua inclusão nas dietas experimentais, até 40 g kg-1 , não afetou a digestibilidade dos nutrientes. Sua inclusão, entretanto, mostrou influenciar negativamente os valores de digestibilidade da proteína, indicando que deve ser mais bem avaliada para que esses possíveis efeitos prejudiciais possam ser superados. Desta forma, o pré-tratamento químico ou biológico do restolho de feijão-frade também foi considerado, pois pode melhorar a digestibilidade deste alimento. Como os fungos da podridão-branca degradam eficientemente a lignina com seu sistema enzimático extracelular e com seu poder de penetração das hifas, estudou-se seu potencial para melhorar o valor nutritivo do restolho de feijão-frade. No Capítulo 3, cinco estirpes de fungos da podridão-branca (Ganoderma lucidum, Lentinula edodes, Pleurotus citrinopileatus, Pleurotus eryngii e Phlebia rufa) foram testadas no pré-tratamento do restolho de feijão-frade por 22 e 45 dias de incubação. Neste estudo, P. citrinopileatus com 22 dias de incubação apresentou os melhores resultados na deslenhificação (-46%) e aumento na digestibilidade in vitro de coelhos (+ 30%) quando comparado com o controlo. Este ensaio forneceu evidências suficientes para produzir maiores quantidades do restolho de feijão-frade tratado, a fim de aumentar os níveis de inclusão nas dietas de coelhos. Para tanto, foram formuladas cinco dietas contendo 50 e 100 g kg-1 de restolho de feijão-frade tratado e 50 e 100 g kg-1 de restolho de feijão-frade não tratado, além da dieta basal (Capítulo 4). Animais alimentados com dietas com restolho de feijão-frade tratado apresentaram um maior peso vivo final (+5%) e uma redução nos níveis de colesterol no sangue (-17%) do que aqueles alimentados com dietas com restolho de feijão-frade não tratado. Como o restolho de feijão-frade é colhida ao mesmo tempo que quantidades elevadas de maçã descartadas estes estão normalmente disponíveis. Sendo assim a possibilidade de usar misturas de ambos os co-produtos e seu potencial para conservação na forma de ensilagem foram avaliadas. Estas silagens podem ser um alimento alternativo durante os períodos de escassez de alimentação. Assim, avaliou-se um novo alimento, ensilagem de maçã descarte (85%) e restolho de feijão-frade (15%) em dois diferentes períodos de ensilagem (45 e 60 dias) sobre valor nutritivo, qualidade de fermentação e estabilidade aeróbia (Capítulo 5). As misturas avaliadas puderam ser conservadas pelo processo de ensilagem. Ambas as silagens, com 45 e 60 dias de ensilagem, apresentaram-se estáveis com baixos valores de pH (≤ 4,0), ausência de ácido butírico e alta estabilidade aeróbia (216h). No entanto, as baixas concentrações residuais de hidratos de carbono solúveis em água das silagens resultantes indicaram que os aditivos de ácido láctico devem ser utilizados para controlar a fermentação microbiana para melhorar o seu valor nutritivo. Além disso, testamos o restolho de feijão-frade tratado com fungos, já avaliado em ensaios anteriores, o potencial de conservação pelo processo de ensilagem juntamente com a maçã descarte (85%) e o efeito do uso de inoculante (Sil-All LV®, Capítulo 6). O tratamento do restolho de feijão-frade, antes da ensilagem, com P. citrinopileatus modificou a composição química e a digestibilidade in vitro, resultando em um aumento do seu valor nutritivo quando comparado com o restolho de feijão-frade não tratado. Silagens inoculadas e não inoculadas com Sil-All permaneceram estáveis após 45 dias de ensilagem, apresentando baixos valores de pH (≤ 4,2) e ausência de ácido butírico. A silagem inoculada apresentou maiores concentrações de ácido láctico e etanol em relação à silagem não inoculada. Por outro lado, ácido acético inferior foi observado na silagem inoculada.

Cowpea (Vigna unguiculata) and moringa (Moringa oleifera) are nutritious and medicinal vegetables, but could also harbor harmful microbial contaminants. The main aim of the project was to determine the effect of each processing techniques on the microbiology, proximate nutrients and shelf life of these vegetables to produce nutritious, tasty, safe and long lasting vegetable products. The processing techniques used were: washing, blanching, and drying. Leaf samples were collected at each stage of processing and were analysed for total viable count, coliform count, yeast and mould count and nutritional content. Microbial plate analysis showed the presence, particularly on cowpea leaves, of yeasts and bacteria such as Pseudomonas, Klebsiella, Staphylococci, Streptococci, and enterobacter including enteropathogens such as Salmonella spp., Shigella dysenteriae and E coli. The presence of E.coli on the leaves was also confirmed using polymerase chain reaction-amplified ribosomal DNA analysis. The most effective processing technique which reduced microbial load to below SABS standards while retaining nutritional quality was the washing of the leaves twice with tap water followed by steam tunnel blanching at 94oC for 12 minutes. Oven drying the leaves at 60oC gave satisfactory and extended shelf life results. Proximate analysis comparison of the two leaf types showed that on average moringa leaves contained more ash (2.37 vs 1.1 g), protein (6,9 vs 3,6 g), fat (0,41 vs 0.2 g) and energy (305,1 vs 70KJ) but less dietary fibre (0,9 vs 7,5 g) than cowpea leaves. No significant differences were noted in these values following washing and steam blanching. These results indicate that washing of these leaves is effective as to reducing microbial load and maintaining proximate values in the short term (up to 4 days) but that oven drying is effective for longer-term storage.
Life and Consumer Sciences
M. Sc. (Life Sciences)