Dissertationen zum Thema „Milk product“

This report presents the primary development process of an innovative milk foamer. The project is structured as the primary development process that is used at Electrolux Floor Care and Small Appliances AB, Global Primary Development and Innovation department in Stockholm, Sweden. The aim was to develop a milk foamer with innovative solutions to provide Electrolux with a unique product. The objective was to create a product that highly meets customer requirements and in the same time is feasible to develop into a selling product. All the aspects regarding a consumer product had to be considered. To create innovative solutions thorough investigations of the physics behind foaming and foam are studied and documented. The difference in foam quality when using different ways of foaming is documented and possible explanations is discussed. The primary development process range from pre-study and customer research to designing prototypes and verifications. Most of the report deals with standalone solutions but there is also a part of the report that deals with integrated solutions and cooperating solutions that would be used together with espresso machines. The result is a variety of concepts and four fully working standalone prototypes. Two prototypes are further developed and are highly interesting to Electrolux.

Mastitis is the most common and economically the most important disease of dairy cattle throughout the world. However in Australia, there is an absence of scientifically based data using herd bulk milk supplies. Animals from each of two farms were divided into three groups based on milk sec and NAGase contents. Milk collected from these animals over a two year period was used to study the influence of sec (as a measure of mastitic infection) on milk composition and milk product quality. Milk compositional studies indicated that log sec was positively correlated to the NCN, BSA, chloride, sodium, NAGase (P<0.005), K-casein, {-casein (P<0.01) and IgG (P<0.05) contents, the pH level (P<0.005) and the NCN:total nitrogen, chloride:lactose and sodium:potassium ratios (P<0.005). Log sec was negatively correlated to the SNF, lactose (P<0.005), ft-casein, ~-lactalbumin, ~-lactoglobulin, soluble calcium (P<0.01), total solids, casein and total calcium (P<0.005) contents and the casein:total protein ratio (P<0.005). When milk samples were grouped into sec categories, results indicated that samples with an sec of greater than 500 000 cells/ml were compositionally inferior to samples with an sec of less than 500 000 cells/ml. Pasteurised milk studies indicated that the organoleptic quality of samples with an sec of less than 1 000 000 cells/ml was generally superior to the organoleptic quality of samples with an sec greater than 1 000 000 cells/ml. Skim milk yoghurt studies indicated that the organoleptic quality of both unsweetened and sweetened yoghurts manufactured from milk with an sec of less than 250 000 cells/ml were superior when compared to yoghurtsmanufactured from milk with an sec of greater than 250 000 cells/ml. The rennet coagulating time of milk was significantly longer when the sec became greater than 500 000 cells/ml. Cheddar cheese manufactured from milk with an sec of greater than 500 000 cells/ml had higher moisture and MFFS and lower fat, FDM and pH. Increased losses of fines (P<0.05) into the whey resulted in lower cheese yields (P<0.10). Log sec was negatively correlated to both cheese flavour and body and texture grades (P<0.10) at six months of age. Cheeses became softer, less springy (P<0.10) and cohesive, more adhesive (P<0.05), and less stringy (P<0.05) as the sec of the milk increased. Skim milk powder studies indicated that the effects of elevated sec on skim milk powder properties and organoleptic quality were minimal. From the results obtained in this study it is suggested that sec threshold values of 1 000 000 and 500 000 cells/ml should be used for market milk and manufacture milk supplies respectively.

The heat-induced gelation properties of ultrafiltered (UF) whole milk concentrate were studied under different physical and chemical conditions. total solids concentration, homogenization pressures, heating temperatures, and heating times were found to have a positive correlation with gel strength. The addition of calcium chloride, sodium chloride, or trisodium citrate produced gels of higher strengths and textural properties than the gels obtained with non-salt-treated concentrate. Calcium chloride produced the strongest gels with a cheese-like texture and poor spreadability. Sodium chloride produced gels of intermediate strength with a firm, elastic texture and poor spreadability. Trisodium citrate produced the softest gels with a smooth, creamy texture and good spreadability. A shelf stable 40% total solids UF concentrate was manufactured using ultra-high temperature (UHT) processing by direct steam injection. The pourable concentrate had a shelf life of 75 to 90 days at 23°C and did not have the ability to produce heat-induced gels after a second heating. Addition of calcium chloride, sodium chloride, or trisodium citrate restored the heat-induced gelation of the retentate. However, the gels were weaker and presented different characteristics than did the gels from non-UHT-treated concentrate. Transmission electron microscopy (TEM) studies revealed a relationship between gel firmness and gel ultrastructure of the heat-induced gels. The gels consisted of a network of casein micelles connected with strands of a less dense protein material. The tighter the network the stronger the gel strength. High heating temperatures and calcium chloride addition caused fusion of the casein micelles int he network. Sensory evaluation of two prototype gelled desserts by a general consumer population showed a good potential for the use of the heat-induced gelation property of UF-concentrated whole milk in the development of new gelled dessert applications.

Temporary price reductions (sales) as a means of promotion have become an increasingly important tool in the marketing mix of food retailers around the world. This paper investigates the retailers' pricing strategy by explicitly accounting for the multi-product nature of retailing. We find that retailers systematically adjust the breadth and depth of sales over time and they respond aggressively to their rivals' promotional activities. Finally, the breadth and depth of sales are found to be substitutes in the set of the available strategies to increase the store traffic. (authors' abstract)

A study was conducted to investigate the use of bacterial numbers and metabolites for their Value in predicting potential shelf-life of pasteurized fluid milk. The study consisted of two phases. In the first phase, chemical inhibitors were evaluated for their ability to allow growth of gram-negative psychrotrophic bacteria while inhibiting growth of gram-positive organisms. Crystal violet, benzalkonium chloride, a mixture of crystal violet and benzalkonium chloride, and alkylaryl sulfonate were tested. These were incubated with milk samples separately inoculated with gram-negative and gram-positive bacteria, at 2l°C for 18 hours. Alkylaryl sulfonate allowed growth of gram-positive organisms. Crystal violet inhibited gram-positive organisms but was not as effective as the mixture of crystal violet and benzalkonium chloride, The inhibitor of choice was benzalkonium chloride as it inhibited growth of all gram-positive organisms tested and allowed growth of the gram-negative psychrotrophic organisms.

Master of Science

An increased interest in functional beverages is occurring, and omega-3 fatty acids (FA) are one of the most commonly sought ingredients to fortify such beverages. Omega-3 FA produce beneficial health effects, likely due to their anti-inflammatory properties. The majority of current omega-3 FA-fortified products include marine-derived omega-3 FA sources, often producing undesired flavors due to lipid oxidation. Little research regarding incorporation of alpha-linolenic acid in functional beverage formulation has been conducted. Alpha-linolenic acid is less susceptible to oxidation and may be a candidate to deliver omega-3 FA into the diet via functional products. Flaxseed is the richest plant source for alpha-linolenic acid; consumption may increase omega-3 FA intake and lower the omega-6:omega3 FA ratio, thereby, attenuating inflammation. Finely ground flaxseed was, therefore, incorporated into a chocolate milk foundation ("flaxmilk") to increase dietary omega-3 FA. An untrained consumer panel tasted and rated flaxmilk's palatability using a 9-point hedonic scale. A score of "6.0" ("like slightly") was targeted. A mean hedonic score of 6.35 was achieved, surpassing the targeted score and indicating an acceptable product. Sensory and analytical analyses of flaxmilk were conducted and compared to standard chocolate milk. Flaxmilk was significantly different in most physical, chemical and sensory characteristics compared to chocolate milk. A reduction in the omega-6:omega-3 FA ratio may attenuate inflammation; inflammation has been linked to osteoporosis. Thus, a secondary analysis of data collected from 202 women was conducted to estimate the dietary omega-6:omega-3 FA ratio and examine relationships between the omega-6:omega-3 FA ratio and total body and site-specific bone mineral density (BMD). The omega-6:omega-3 FA ratio had no appreciable association with any measure of BMD in the overall sample of women or in younger or older subsamples of women. In summary, consumers found flaxmilk to be an acceptable product, despite sensory and compositional differences compared to chocolate milk. The relationship between the omega-6:omega-3 FA ratio and BMD remains unclear.
Ph. D.

The traditional way of processing milk is the application of heat to destroy undesirable microorganisms. Though heat is an effective means of doing the job, it is associated with several limitations. High pressure (HP) processing has the potential for eliminating microorganisms without affecting the natural quality of the raw material. As a result, it has become a promising technique in recent years. Many factors are reported to influence HP destruction of microorganisms, the most important ones include food composition (i.e., lipid, carbohydrate and protein contents), water activity, process temperature, and mode of pressure treatment. Therefore, the objectives of this research were to: (a) evaluate the effect of milk composition on destruction of E. coli by HP, (b) evaluate kinetic models for spoilage and pathogenic microorganism in milk and the effect of different pressure mode (pulse and static) on the destruction rates; and (c) to evaluate the effect of milk type (UHT and raw milk) and temperate on destruction of microorganism.

Effects of dairy fat composition on LDL metabolism were measured in male guinea pigs fed 15% (w/w) fat diets, either butterfat (BF) or a synthetic butter-like fat mix (SBF). Dietary groups were: whole milk powder (WM), skim milk powder-SBF (SM/S), casein-SBF (C/S), and skim milk powder-BF (SM/B). A hypocholesterolemic effect was observed in guinea pigs fed the WM (plasma cholesterol, 1.5 mmol/L) diet compared to all other diet groups (3. 1 mmol/L). Hepatic LDL receptor B(max) and K(d) values were not different between WM and SM/B diet groups. Animals fed the WM or SM/B diets had higher HMG-CoA reductase activities than animals fed the SM/S or C/S diets. The results demonstrate that butterfat intake results in a hypercholesterolemic response of plasma and liver; however, the predicted hypercholesterolemic effect of miikfat was not observed with the WM diet compared to the SBF and BF fats. These data suggest that some factor(s) in milk, other than the milkfat itself, negates the hypercholesterolemic effect of dairy fat. Additional experiments evaluated the effects of diet supplemented with whole milk and partially reconstituted milk fractions in guinea pigs fed diets containing 15% (w/w) butter-palm oil (1:1) fat, with or without liquid milk products. Dietary groups were: water (WE), non-processed whole milk (NPWM), re-constituted whole milk (RCWM), buttermilk-enriched skim milk (BMSM), butterserum-enriched skim milk (BSSM), and butteroil-skim milk (BOSM). Plasma total cholesterol (3.0 ± 1.4 versus 2.6 ± 0.1 mmol/L) and hepatic cholesterol (8.1 ± 0.6 versus 9.0 ± 1.2 μmol/g) were not different between WE and milk product treated diets. LDL peak densities and calculated diameters, and hepatic LDL receptor B(max) and K(d) were not different among diets. In summary, potential plasma cholesterol lowering factor(s) associated with whole milk may exist in buttermilk or butterserum but can not be identified; however, a diet supplemented with liquid milk products providing up to 46% of the daily energy intake, with higher total fat (1.4-fold) and dietary cholesterol (2.3-fold) did not increase plasma cholesterol and triacylglycerol levels or alter LDL metabolism in the guinea pig.

Complex foodborne threats to public health and safe food supplies are increasing with each passing day, serving as a great challenge to food corporations today. This thesis, selecting the Mengniu Dairy milk scandal as the subject of the study, is aimed to examine how newspapers reported and evaluated Mengniu milk crisis and crisis management in the 2008 Chinese milk scandal and to provide suggestions to Mengniu Dairy's crisis management, as well as the Chinese food industry in general. It is a significant step towards exploring the crisis management strategy of a food company in a non-Western setting under a circumstance in which crisis responsibility is ambiguous. To accomplish this, a content analysis of 253 articles ranged from September 11, 2008, to September 10, 2009, on 10 Chinese newspapers' Web sites was conducted. The results of the coding supported an argument that apology and product recall were not good enough for the milk crisis and identified the significant role of the Chinese government in food crisis management. Two suggestions are offered by the study. First, building a good external relationship and cooperating with the local government. Second, being proactive and addressing public safety during the pre-crisis stage. Further, recommendations for further study are enclosed.

Probiotic bacteria are increasingly prevalent in food and nutritional products today. These remarkable microorganisms are capable of imparting exceptional health benefits on their host, including prevention of infection by pathogens and stimulation of immune system function. Their most common mode of delivery is through dairy products (e.g. yogurt), which are also one of their preferred habitats. The interactions between probiotic bacteria and dairy systems have been studied, but are still not well discerned. There is a need for better understanding of these associations, as well as those surrounding the mode of bacterial transfer from the food product to the human gastrointestinal tract. Discoveries into the optimal means of probiotic transport to the body may lead to great advancements in both the design of probiotic foods and their exploitation in the support of human health. Much of the previous research on probiotic bacteria has explored their possible means of adherence in the intestine, as well their strengths in the promotion of human health. Studies relating to their interaction with dairy products are lacking, however, thus this work aims to elucidate some of these aspects. The primary endeavor of this thesis was to develop a technique to quantify the binding affinity of probiotic lactic acid bacteria for milk phospholipids. An additional objective was to exploit these bacteria, as well as dairy ingredients rich in bioactive molecules, in the creation of a highly nutritious food product. In these experiments, a collection of methods were used in progression in order to arrive at a novel protocol to assess binding with excellent reproducibility and simplicity. These included various membrane blotting techniques, as well as thin-layer chromatography. Essentially, phospholipids from both animal-derived standards and milk extracts were applied to a surface (e.g. PVDF membrane), and bacteria were incubated with them to allow binding reactions. The lactic acid bacteria selected for the final assays consisted of four strains of Lactobacillus, including L. reuteri (SD2112 and T-1), L. acidophilus, and L. casei (LC-10). Their adhesion to phospholipids was detected by either colorimetric or fluorescent labeling systems. To illustrate this, the final method developed was a procedure in which bacteria fluorescently stained with acridine orange were allowed to bind to dots of PVDF membrane coated with phospholipids. The results of this study showed that lactic acid bacteria undeniably exhibit selective binding affinity for phospholipids as opposed to other lipids such as triglycerides. The bacteria demonstrated significantly greater binding for a phospholipid extract from milk as opposed to individual phospholipid standards from other sources (p<0.05). Nonetheless, adhesion to all phospholipids was substantially greater than that to triglycerides. These findings, as well as the development of this method, should prove valuable in future research regarding the associations of probiotics with dairy systems. An additional purpose of this thesis was to design a dairy-based food product containing ingredient sources rich in milk bioactives. A gel-type product was created using primarily colostrum, buttermilk powder, and whey protein isolate, as well as selected strains of Lactobacillus. With the inclusion of immunoglobulin-rich colostrum, the product was analyzed alongside fluid milk and colostrum in order to quantify and compare these bioactive molecules. An enzyme-linked immunosorbent assay (ELISA) was used to complete this, and the results revealed concentrations that would be expected by the literature. Specifically, immunoglobulin G (IgG) was quantified by interpolation from a bovine IgG standard regression curve. The results showed that the concentration of IgG in the gel was nearly twice that of colostrum, and almost eight-fold higher than that of milk. This indicates that use of bioactive-rich substances, such as colostrum, in a food product may serve as a means of delivering more concentrated doses of bioactives than their respective ingredients. The research completed in this thesis is significant in that it contributes a valuable method to the elucidation of bacterial binding interactions with milk components, and also demonstrates the successful application of dairy ingredients to an innovative food product high in beneficial compounds. The insight provided by these studies could encourage further work in improving the understanding of probiotic delivery and advancing the development of bioactive-rich food products.

Щерба, Л. В. Проєктування цеху з переробки молока у фермерському господарстві на 100 корів : випускна кваліфікаційна робота : 181 «Харчові технології» / Л. В. Щерба ; керівник роботи В. М. Челябієва ; НУ "Чернігівська політехніка", кафедра харчових технологій. – Чернігів, 2021. – 94 с.
Основною метою даної роботи є проектування сучасного виробничого цеху на фермерському господарстві з виготовлення молочної продукції. У роботі висвітлено основні проблеми розвитку молочної промисловості в Україні, наведені статистичні дані, щодо кількості поголів’я великої рогатої худоби та підприємств з переробки молока; наведені основні розрахунки продукції заданого асортименту та технологічна схема напрямків переробки сировини, основні нормативні характеристики, яким має відповідати вхідна сировина та готова продукція, описані загальні технологічних операцій при виготовленні продукції запроектованого асортименту та технологія виробництва, відповідно до апаратурно-технологічної схеми; наведені передумови для впровадження НАССР на виробництві, визначені та обґрунтуванні критично-контрольні точки. Також у роботі висвітлені питання промислової санітарії, заходів щодо охорони навколишнього середовища та організація охорони праці під час виробництва.
The main purpose of this work is to design a modern production plant on a farm for the manufacture of dairy products. The paper highlights the main problems of development of the dairy industry in Ukraine, provides statistics on the number of cattle and milk processing enterprises; the basic calculations of production of the set assortment and the technological scheme of directions of processing of raw materials, the basic normative characteristics to which the input raw materials and finished goods should correspond, the general technological operations at manufacturing of products of the designed assortment and production technology according to the hardwaretechnological scheme are given; the preconditions for the implementation of HACCP in production are given, the critical control points are defined and substantiated. The paper also covers issues of industrial sanitation, environmental protection measures and the organization of labor protection during production.

Darbo tikslas – atlikti Lietuvos pieno sektoriaus pokyčių analizę Lietuvai tapus Europos sąjungos nare. Darbe buvo tiriama Europos Sąjungos pieno rinkos, struktūrinės paramos ir rinkos organizavimo priemonių įtaka Lietuvos pieno sektoriui. Tyrimas atliktas naudojant statistinius ir matematinius duomenų analizės ir grafinio vaizdavimo, lyginamosios analizės, mokslinės literatūros analizės ir sintezės metodus. ES bendrosios rinkos atsivėrimas, struktūrinė parama ir rinkos organizavimo priemonės turėjo didžiausią poveikį Lietuvos pieno ūkių struktūriniams pokyčiams bei pieno ir pieno produktų paklausai ir konkurencingumui. 2004 – 2008 metais bendra pieno kvota ir pardavimo perdirbti pieno kvota padidėjo, o pardavimo tiesiogiai vartoti pieno kvota sumažėjo. Tačiau pieno kvotos dėl nepakankamo pieno gamybos organizavimo nebuvo įvykdytos. Pieno kvotų turėtojų skaičius kasmet mažėjo dėl pieno ūkių stambėjimo bei asmenų pasitraukimo iš žemės ūkio gamybos. Didėjant pieno gamybai, augo pieno ir pieno produktų prekyba su ES šalimis bei pajamos dėl padidėjusių rinkos kainų. 2007 metais sumažėjo sviesto, s��rių ir varškės, laktozės ir kazeino eksportas dėl sumažėjusios šių produktų gamybos ir pieno naudojimo kitų pieno produktų gamybai. Ledų eksportas ir importas didėjo dėl didėjančios šių produktų paklausos rinkoje. Stambėjant pieno ūkiams ženkliai sumažėjo pieno ūkių, kuriuose buvo laikoma 1 – 4 karvės, skaičius. Padidėjo pieno ūkių, kuriuose buvo laikoma daugiau kaip 30 karvių... [toliau žr. visą tekstą]
Aim of the work was to analyze changes in Lithuanian milk sector after accession to EU. Impact of EU common market and support provided by structural funds and market support means was studied. Statistical and descriptive analysis of findings was applied. Study showed, that EU common market, structural funds and market support means have had the biggest impact to Lithuanian milk sector. In 2004 – 2008 common milk quota and quota for the milk delivery were increased. Quota for direct milk sale was reduced. However milk quota has never been delivered. Enlargement of farms and early retirement of farmers have reduced a number of keepers of milk quota. Growing milk production and common market has raised trade in dairy products. Milk has been used for production of variety of dairy products. In 2007 there was some decrease in trade of butter, cheese and cottage cheese, lactose and casein. There was high demand of ice-cream on the market. Enlargement and modernization of milk sector have significantly decreased a number of dairy farms keeping 1 – 4 cows. Dairy herds have improved in milk yield and milk quality.

En els últims 10 anys s'ha incrementat la recerca en emulsions per a l'alliberament de compostos bioactius. Les emulsions convencionals d'oli-en-aigua (> 1 µm) presenten una estabilitat fisicoquímica i oxidativa insuficient; per tant, i per superar aquest problema, s'han dut a terme molts esforços en el desenvolupament de noves tecnologies. La tecnologia d'Homogeneïtzació a Ultra-Alta Pressió (UHPH) s'ha aplicat en diferents emulsions alimentàries per tal de millorar la seva estabilitat física. Per això, és necessari el desenvolupament d'emulsions UHPH d'oli-en-aigua que continguin bioactius lipòfils, com l'àcid linoleic conjugat (CLA), per tal de millorar les característiques nutricionals i fisicoquímiques de les emulsions, així com la seva vida útil. En aquesta tesi doctoral, es va avaluar la influència de diferents tecnologies (UHPH i homogeneïtzació convencional; CH) i ingredients (aïllat proteic de soja, SPI; aïllat proteic de pèsol, PPI; oli de soja i CLA) en emulsions d'oli-en-aigua. A més, es va desenvolupar un producte final de base làctia UHT incorporant emulsions amb CLA. La present recerca es va dividir en quatre parts. En un primer estudi, es va avaluar l'efecte de la UHPH (100-300 MPa, Ti=20 °C) en comparació de la CH (15 MPa, Ti=20 °C) sobre l'estabilitat física i oxidativa d'emulsions d'oli de soja (10 i 20%) i estabilitzades amb SPI per tal de determinar les formulacions més estables. A més, la desnaturalització completa de l'SPI (95 °C, 15 min) es va realitzar abans del tractament CH amb l'objectiu d'analitzar la possibilitat d'obtenir característiques millorades de les emulsions. En concret, les emulsions UHPH tractades a 100 i 200 MPa amb un 20% d'oli van ser les més estables a nivell físic i oxidatiu a causa de la disminució de la mida de partícula, la major quantitat d'oli, i una major viscositat i quantitat de proteïna a la interfase oli-en aigua. El tractament tèrmic de l'SPI no va millorar l'estabilitat física de les emulsions, però sí l'estabilitat oxidativa quan es va utilitzar un 10% d'oli. El segon estudi consistí en la producció de diferents emulsions (20% d'oli) estabilitzades amb SPI i PPI i emprant 1 i 5 etapes de CH (55 MPa, Ti=20 °C) per avaluar l'eficiència d'encapsulació de CLA (6%), així com el seu alliberament i bioeficàcia utilitzant la digestió in vitro i un model cel·lular Caco-2 d'absorció intestinal. Totes les emulsions van protegir millor el CLA encapsulat a diferència del control (CLA en forma lliure), el qual es va oxidar durant l'emmagatzematge, així com després de la digestió in vitro i consegüent alliberament en les cèl·lules Caco-2. Es van trobar percentatges similars de biodisponibilitat del CLA en totes les emulsions. Un tercer estudi va avaluar l'efecte de la UHPH (200 MPa, Ti=20 °C) en les emulsions amb CLA en comparació a la CH (15 MPa, Ti=20 °C). Per a un altre lot de emulsions CH, també es va dur a terme un tractament tèrmic de pasteurització. La UHPH va produir una emulsió estèril i durant l'emmagatzematge, va mostrar millor estabilitat física en comparació amb els altres tractaments, i a més, va mantenir una òptima estabilitat oxidativa. Un cop més, es varen trobar percentatges similars de biodisponibilitat del CLA en totes les emulsions. En un l'últim estudi, es va avaluar la incorporació d'emulsions amb CLA tractades per UHPH (200 MPa, Ti=20 °C) i CH (15 MPa, Ti=20 °C) en un producte de base làctia UHT. El producte final que contenia les emulsions UHPH va mostrar una estabilitat fisicoquímica i propietats sensorials millorades durant 4 mesos d'emmagatzematge.
En los últimos 10 años se ha incrementado la investigación en emulsiones para la liberación de compuestos bioactivos. Las emulsiones convencionales de aceite-en-agua (> 1 µm) presentan una estabilidad fisicoquímica y oxidativa insuficiente; por lo tanto, y para superar este problema, se han llevado a cabo muchos esfuerzos en el desarrollo de nuevas tecnologías. La tecnología de Homogeneización a Ultra-Alta Presión (UHPH) se ha aplicado en diferentes emulsiones alimentarias con el fin de mejorar su estabilidad física. Por estas razones, es necesario el desarrollo de emulsiones UHPH de aceite-en-agua que contengan bioactivos lipófilos, como el ácido linoleico conjugado (CLA), con el fin de mejorar las características nutricionales y físico-químicas de las emulsiones, así como su vida útil. En esta tesis doctoral, se estudió la influencia de diferentes tecnologías (UHPH y homogeneización convencional; CH) e ingredientes (aislado proteico de soja, SPI; aislado proteico de guisante, PPI; aceite de soja y CLA) en emulsiones de aceite-en-agua. Además, se desarrolló un producto final de base láctea UHT conteniendo emulsiones con CLA. La presente investigación se dividió en cuatro partes. En un primer estudio, se evaluó el efecto de la UHPH (100-300 MPa, Ti=20 °C) en comparación a la CH (15 MPa, Ti=20 °C) sobre la estabilidad física y oxidativa de emulsiones de aceite de soja (10 y 20%) y estabilizadas con SPI, con el fin de determinar las formulaciones más estables. Además, se desnaturalizó el SPI (95 ° C, 15 min) antes del tratamiento CH con el objetivo de analizar la posibilidad de obtener características de las emulsiones mejoradas. En concreto, las emulsiones UHPH tratadas a 100 y 200 MPa con un 20% de aceite fueron las más estables a nivel físico y oxidativo debido a la disminución del tamaño de partícula, la mayor cantidad de aceite, y una mayor viscosidad y cantidad de proteína en la interfase aceite-en-agua. El tratamiento térmico del SPI no mejoró la estabilidad física de las emulsiones, pero sí la estabilidad oxidativa cuando se utilizó un 10% de aceite. El segundo estudio consistió en la producción de diferentes emulsiones (20% de aceite) estabilizadas con SPI y PPI, y se emplearon 1 y 5 pases de CH (55 MPa, Ti=20 °C) para determinar la eficiencia de encapsulación de CLA (6%), su liberación y bioeficacia utilizando la digestión in vitro y un modelo celular Caco-2 de absorción intestinal. Todas las emulsiones protegieron mejor el CLA encapsulado a diferencia del control (CLA en forma libre), el cual se oxidó durante el almacenamiento, así como después de la digestión in vitro y consiguiente liberación en las células Caco-2. Se encontraron porcentajes similares de biodisponibilidad del CLA en todas las emulsiones. Para evaluar el efecto de la UHPH (200 MPa, Ti=20 °C) en las emulsiones con CLA en comparación a la CH (15 MPa, Ti=20 °C), se realizó un tercer estudio. Para otro lote de emulsiones CH, también se llevó a cabo un tratamiento térmico de pasteurización. La UHPH produjo una emulsión estéril y durante el almacenamiento, mostró mejor estabilidad física en comparación a los otros tratamientos, y además, mantuvo una óptima estabilidad oxidativa. Una vez más, se encontraron porcentajes similares de biodisponibilidad del CLA en todas las emulsiones. En un el último estudio, se evaluó la incorporación de emulsiones con CLA tratadas por UHPH (200 MPa, Ti=20 °C) y CH (15 MPa, Ti=20 °C) en un producto de base láctea UHT. El producto final que contenía las emulsiones UHPH mostró una mayor estabilidad físico-química y propiedades sensoriales mejoradas durante 4 meses de almacenamiento.
Research on delivery of bioactive compounds by emulsion-based systems has increased over the last 10 years. Conventional oil-in-water emulsions (>1 μm) have poor physicochemical and oxidative stability; therefore, many efforts on novel technologies development have been employed to overcome this problem. Ultra-High Pressure Homogenization (UHPH) technology has been applied in different food emulsions in order to improve their physical stability. For these reasons, development of UHPH oil-in-water emulsions containing lipophilic bioactives, such as conjugated linoleic acid (CLA), to improve their physicochemical and nutritional characteristics and shelf-life is needed. In this thesis dissertation, the influence of different technologies (UHPH and Conventional Homogenization; CH) and ingredients (soy protein isolate, SPI; pea protein isolate, PPI; soybean oil and CLA) in oil-in-water emulsions was evaluated. In addition, a final UHT milkbased product containing CLA-emulsions was developed. This research has been divided into four parts. The first part studied the effect of UHPH (100- 300 MPa, Ti=20 °C) compared to CH (15 MPa, Ti=20 °C) on physical and oxidative stability of soybean oil (10 and 20%) emulsions stabilized by SPI was assessed in order to determine the most stable formulations. Also, complete denaturation of SPI (95 °C, 15 min) before CH treatment was performed with the aim of analyzing possible improvement of emulsion characteristics. Particularly, UHPH emulsions treated at 100 and 200 MPa with 20% of oil were the most physically and oxidatively stable due to low particle size values, higher amount of oil, and greater viscosity and protein surface load at the interface. The heating of SPI did not improve physical stability of emulsions but enhanced oxidative stability when 10% oil was used. The second study consisted in the assessment of different emulsions (20% oil) stabilized by SPI and PPI and homogenized by CH (55 MPa, Ti=20 °C) for 1 and 5 passes on the efficiency of 6% CLA encapsulation, its release and bioefficacy using in vitro digestion and a Caco-2 intestinal cell absorption model. All emulsions protected the encapsulated CLA better than the nonemulsified control in which CLA was oxidized during storage, as well as after in vitro digestion and delivery in Caco-2 cells. Similar percentages of CLA bioavailability were found for all emulsion treatments. To evaluate the effect of UHPH (200 MPa, Ti=20 °C) in CLA-emulsions in comparison to CH (15 MPa, Ti=20 °C), a third study was performed. For another batch of CH emulsions, a heat treatment was also conducted applying a pasteurization treatment. UHPH produced a sterile CLA-emulsion and showed better physical stability during storage compared to other treatments, maintaining an optimal oxidative stability. Again, similar percentages of CLA bioavailability in Caco-2 cells were found for all emulsion treatments. In the last study, the incorporation of CLA-emulsions obtained by UHPH (200 MPa, Ti=20 °C) and CH (15 MPa, Ti=20 °C) in a UHT milk-based product was evaluated. The final product containing the UHPH emulsions showed enhanced physicochemical stability and sensory properties during 4 months of storage.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The ricotta cheese is a smooth flavor, obtained from the coagulation of the whey proteins in cheese with or without the addition of milk. May be fresh, creamy, aged or cured and can be consumed as cream cheese board or in combination with other ingredients in culinary dishes. The preparation of ricotta is an alternative to reusing whey, a co-product of high nutritional value generated in large quantities during processing of the cheese milk to obtain a curd type. In this study was to develop a base of creamy ricotta cheese curd goat whey (40%) and bovine (40%) as main ingredients, with added goat milk (10%) and bovine (10%). The technological characteristics, physicochemical and sensory texture of creamy ricotta were evaluated during refrigerated storage for 14 days. The yield of the process of getting the creamy ricotta was 7.9% and syneresis ranged from 5 to 7% during the study period. During storage, moisture (73.81 to 74.59), the lipid content (8.83 to 9.08) and total solids (25.63 to 26.19) remained stable (p >0,05), while the protein content and ash varied (p <0,05). The instrumental texture profile characterized the creamy ricotta cheese as an easily deformable, inelastic, cohesive, soft texture and delicate, unchanged after 14 days of storage. In the analyzes of instrumental color was observed reduction of yellowing and green tones during cold storage of 14 days. In Quantitative Descriptive Analysis (QDA) flavor and aroma of creamy ricotta goat were described by the panel as soft, wet appearance and soft texture and creamy. O fatty acid profile showed that the fatty acid content of medium and long chain (C14:0, C16:0, C18:0, C18:1n9c and C18:2n6c) was superior to just short chain acid (C6:0) and capric (C:10) decreased (p <0,05) during storage. Among the 14 identified amino acids, threonine, isoleucine, leucine and phenylalanine were increased during the study period, while methionine, lysine and alanine decreased. The results indicate that the use of the mixture of whey curd goat and bovine as the main ingredient of creamy ricotta mixed is viable and not reflected in negative features in the product, suggesting a promising use for reusing the coproduct.
A ricota é um queijo de sabor leve, obtido a partir da coagulação das proteínas do soro de queijos com ou sem a adição de leite. Pode ser fresca, cremosa, maturada ou defumada e pode ser consumida como queijo cremoso de mesa ou em combinação com outros ingredientes em pratos culinários. A elaboração da ricota constitui uma alternativa para o reaproveitamento do soro, co-produto de elevado valor nutricional gerado em grandes quantidades durante o processamento do leite para obtenção de queijo tipo coalho. No presente estudo foi elaborada uma ricota cremosa a base de soros de queijo coalho caprino (40%) e bovino (40%) como ingredientes principais, com adição de leite integral de cabra (10%) e de vaca (10%). As características tecnológicas, físico-químicas, de textura e sensoriais da ricota cremosa foram avaliadas durante armazenamento refrigerado por 14 dias. O rendimento do processo de obtenção da ricota cremosa foi de 7,9% e a sinerese variou de 5 a 7% no período estudado. Durante o armazenamento, a umidade (73,81-74,59), o teor de lipídios (8,83-9,08) e extrato seco total (25,63-26,19) permaneceram estáveis, (p>0,05), enquanto os teores de proteínas e cinzas variaram (p<0,05). O perfil de textura instrumental caracterizou a ricota cremosa como um queijo facilmente deformável, pouco elástico, coeso, de textura macia e delicada, sem alterações após 14 dias de armazenamento. Nas análises de cor instrumental foi observado amarelecimento e redução dos tons de verde durante o armazenamento refrigerado de 14 dias. O sabor e aroma caprino da ricota cremosa foram descritos pelo painel da Análise Descritiva Quantitativa (ADQ) como suaves, a aparência como molhada e a textura como macia e cremosa. O perfil de ácidos graxos mostrou que o conteúdo de ácidos graxos de cadeia média e longa (C14:0; C16:0; C18:0; C18:1n9c e C18:2n6c) foi superior ao de cadeia curta (C6) e apenas o ácido cáprico (C:10) diminuiu (p<0,05) durante o armazenamento. Dentre os 14 aminoácidos livres identificados, treonina, isoleucina, leucina e fenilalanina tiveram aumento nos teores no período estudado, enquanto metionina, lisina e alanina diminuíram. Os resultados indicam que o uso da mistura de soro de queijo coalho caprino e bovino como ingrediente principal de ricota cremosa mista é viável e não repercute em características negativas no produto, sugerindo um emprego promissor para o reaproveitamento do co-produto.

SimGas B.V. is a Dutch company and is today the largest supplier of biogas systems in EastAfrica. Since 2013, SimGas has been developing a biogas-driven milk chiller in order to provide a solution to the milk spoilage problem of small-scale dairy farmers in East-Africa. In this project, a case study was conducted to identify the challenges of applying sustainability and usability in developing a product for an East-African market. In the case study, Ellinore Seybolt and Carrie Zhong, Master students of Industrial Design Engineering at KTH Royal Institute of Technology, joined the process of developing a biogas-driven milk chiller for East-African farmers as interns at the company SimGas B.V. in The Hague, The Netherlands. The project was performed in close collaboration with the research and development team of the Biogas Milk Chiller. As part of this collaboration, the structure of the project was adapted to fit SimGas’ agile way of working. This resulted in that the project was divided in sprints. Participating in a design process for users overseas from a different culture and with the absence of direct contact with the users proved to be a challenge. Towards the end, Ellinore and Carrie got the opportunity to meet users in a field trip that could validate many assumptions made in the beginning of the project, such as that it was indeed the wife of the household who would be the main user. Furthermore, it proved challenging to design for sustainability with a low target cost price and when promising materials found, they were not yet ready for the market. To propose a sustainable disposal of the remains of the product in East-Africa, also proved to be challenging when the available facilities were unknown. Another challenge was to integrate into the culture of a small Dutch company as Swedish interns. The project resulted in alternative design solutions for the Biogas Milk Chiller that would improve the usability and sustainability of the product. The conclusions of this project can also be seen as a foundation for design choices of future Biogas Milk Chiller concepts for SimGas B.V.
SimGas B.V. är ett nederländskt företag som i dagsläget är den största leverantören av biogassystem i Östafrika. Sedan 2013 har SimGas utvecklat en biogasdriven mjölkkylare för att förse en lösning på problemet med mjölk som surnar för småskaliga mejeribönder i Östafrika. I detta examensarbete har en fallstudie gjorts för att identifiera utmaningarna av att tillämpa hållbarhet och användarvänlighet inom en produktutvecklingsprocess mot den östafrikanska marknaden. I fallstudien tog Ellinore Seybolt och Carrie Zhong, mastersstudenter inom Teknisk Design på Kungliga Tekniska Högskolan, del av produktutvecklingsprocessen för en biogasdriven mjölkkylare riktad mot östafrikanska bönder, som praktikanter hos SimGas B.V. i Haag, Nederländerna. Projektet utfördes i nära samarbete med utvecklingsgruppen för produkten. Projektet anpassades utefter SimGas agila sätt att arbeta. Det resulterade i att projektet blev uppdelat i sprintar. Att ta del av en utvecklingsprocess riktad mot användare från en annan kontinent och kultur utan att ha direkt kontakt med dem visade sig vara utmanande. Mot slutet av projektet gjordes en fältresa där antaganden som gjorts i början av projektet kunde bekräftas, som att det var frun i hushållet som skulle vara huvudanvändaren. Det visade sig även att vara en utmaning att utveckla produkten ur ett mer miljövänligt perspektiv då budgeten var låg och hittade lovande material inte ännu fanns tillgänglig på marknaden. Att hitta en lösning på hur produkten skulle kunna skrotas på ett ansvarsfullt sätt var också utmanande då det var svårt att få information om vilka möjligheter som fanns i Östafrika. Ännu en utmaning var att som svenska praktikanter integrera i den nederländska företagskulturen. Projektet resulterade i alternativa designlösningar för den biogasdrivna mjölkkylaren som skulle öka dess användarvänlighet och miljövänlighet. Resultatet av arbetet kan även tänkt att kunna användas av SimGas som underlag för framtida designval kring mjölkkylaren.

Idag sker många transporter med låg utnyttjandegrad vilket gör att transportkostnaden per produkt blir hög samtidigt som transporter har en negativ påverkan på miljön. Genom att konsolidera transporter kan utnyttjandegraden av transporterna öka. Ökad utnyttjandegrad kan även hjälpa företagen att gå mot cirkulär ekonomi där målet är att utnyttja resurserna maximalt. För små och medelstora företag kan det dock vara svårt att bygga upp samarbeten med andra företag. Dessa företag möter olika möjligheter och hinder vid implementering av transportkonsolidering, därför kommer denna studien identifiera vilka dessa är. Studien har genomförts i samarbete med 16 företag i Orust kommun och har visat att de största hindren vid transportkonsolidering är kundkrav, produktkrav och informationsdelning. Företagen upplevde att kundernas krav på korta ledtider skulle göra det svårt att samordna transporter med andra företag. Många företag upplevde även att produktkraven deras produkter ställer på transporterna skulle försvåra transportkonsolidering. Studien kunde dock visa att flera företag hade liknande produktkrav vilket möjliggör transportkonsolidering. En del företag ansåg att det saknades stöd och samarbete för den informationsdelning som krävs vid konsolidering. De främsta möjligheterna som identifierades är företagskulturen och viljan att gå mot en mer hållbar distributionskedja. Företagen som deltog i intervjuerna nämnde att de såg positivt på transportkonsolidering om det fanns ett sätt att enkelt samordna transporterna. De är även aktiva i Orust Kretsloppsakademi som arbetar för ett hållbart Orust vilket visar att det finns ett intresse av att bli mer hållbara.
Today, many transports are at a low rate of utilization. This means that shipping costs per product will be high and at the same time transports have a negative impact on the environment. Consolidating transports can increase the utilization rate for transports which minimizes costs and environmental impact. Increased utilization rates can also help companies move towards circular economics where the goal is to maximize their utilization of resources. However, for small and medium size companies it may be difficult to build up partnerships with other companies. These companies face different possibilities and obstacles in implementing transport consolidation, therefore this study will identify these. The study has been carried out in cooperation with 16 companies in Orust and has shown that the main obstacles to transport consolidation are customer requirements, product requirements and information sharing. The companies perceived that customer demand for short lead times would make it difficult to coordinate transport with other companies. Many companies also found that the productrequirements of their products on transport would make transport consolidation difficult. However, the study showed that several companies had similar product requirements, which enables transport consolidation. Some companies also felt that there was no support and cooperation for the information sharing required for consolidation. The main opportunities identified were corporate culture and the desire to move towards a more sustainable distribution chain. The companies that participated in the interviews mentioned that they can see possibilities of transport consolidation if there was a way to easily coordinate transport. They are also active in the Orust Kretsloppsakademi that works for a sustainable Orust, which shows that there is an interest in becoming more sustainable.

Zvýšená konzumace fermentovaných mléčných výrobků v posledních letech vede k zavádění nových výrobků na trh. Funkční a probiotické produkty jsou v dnešní době také hojně rozšířeny. Cílem diplomové práce bylo posoudit mikrobiální kvalitu komerčních jogurtů a nefarmakologických probiotických výrobků. Bylo zkoumáno 24 vzorků jogurtů a 8 vzorků probiotických mléčných výrobků. Pozornornost byla zaměřena zvláště na kvantifikaci mikroorganismů v jednotlivých výrobcích a na sledování viability buněk. Většina mléčných produktů obsahovala počty odpovídající minimální požadované hodnotě 1x107cfu/ml. Nicméně byly objeveny produkty, které neobsahovaly živé bakterie nebo obsahovaly jen jejich menší množství. To platí zejména pro běžné jogurty. Probiotické mléčné výrobky v zásadě obsahovaly větší množství bakterií než jogurty, protože je u nich navíc požadováno 1x106cfu/ml minimálního množství specifických bakterií jiných než jogurtových startovacích kultur. Isoláty z fermentovaných mléčných výrobků byly identifikovány jako Streptococcus thermophilus and Lactobacillus spp. Isoláty byly poté rozlišeny na jednotlivé kmeny pomocí RAPD použitím tří různých primerů. Byla zjištěna velká různorodost mezi kmeny rodu Lactobacillus spp. používaných různými podniky.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
Este trabalho foi conduzido com o objetivo de avaliar o desempenho e a qualidade do leite de cabras leiteiras alimentadas com dietas contendo alimento extrusado à base de farelo de mamona (AEFM) na alimentaÃÃo de cabras leiteiras. Quatro grupos de cinco fÃmeas caprinas da raÃa Saanen, foram alimentadas por 34 dias com dietas diferenciadas nos nÃveis de substituiÃÃo do farelo de soja por AEFM: 0, 33, 67 e 100%. NÃo houve efeito dos tratamentos (P>0,05) sobre os nutrientes consumidos avaliados: matÃria seca (g/d, %PV, g/kg PV0,75), proteÃna bruta (g/d e g/kg PV0,75), extrato etÃreo (g/d e g/kg PV0,75), fibra em detergente neutro (g/d, %PV e g/kg PV0,75), carboidratos nÃo fibrosos (g/kg PV0,75) e carboidratos totais (g/d e g/kg PV0,75). O consumo de carboidrato nÃo fibroso (g/d) foi influenciado (P<0,05), apresentando relaÃÃo linear positiva com o aumento do nÃvel de inclusÃo de AEFM. Houve influencia dos tratamentos sobre os nutrientes DMS, DMO, DPB, DEE e DFDN, ocasionando efeito linear decrescente (P<0,05). Assim como tambÃm na DCNF que apresentou efeito quadrÃtico (P<0,05) aos nÃveis de substituiÃÃo. NÃo houve influencia dos tratamentos (P>0,05), sobre os parÃmetros de nitrogÃnio consumido, nitrogÃnio excretado na urina, nitrogÃnio excretado no leite, balanÃo de nitrogÃnio, nitrogÃnio de excreÃÃo total e nitrogÃnio endÃgeno basal. Observou-se que os valores encontrados para o nitrogÃnio fecal, foram influenciados (P<0,05). Nos parÃmetros da composiÃÃo fÃsico-quÃmica do leite, observou-se que nÃo houve influÃncia (P>0,05) sobre a produÃÃo de leite (PL), composiÃÃo em proteÃna bruta do leite (PBL) e gordura do leite (GL). Os valores mÃdios de nitrogÃnio urÃico do leite (NUL) foram influenciados (P<0,05), quando comparados com a dieta controle. NÃo houve efeito (P>0,05) sobre a lactose (LAC) e sÃlidos totais (ST). Para as variÃveis de extrato seco desengordurado e rendimento de queijo, houve influÃncia (P<0,05), com mÃdia de 76,42g.kg-1 e 22,25%. Os teores na concentraÃÃo dos Ãcidos graxos butÃrico (C4:0) e caprÃlico (C8:0), foram influenciados (P<0,05) quando comparada ao tratamento controle. NÃo houve efeitos (P>0,05), sobre os teores de Ãcidos graxos saturados (AGS), Ãcidos graxos insaturados (AGI), Ãcidos graxos poliinsaturados (AGP). Para o Ãndice de aterogenicidade (IA), observou-se influencia (P<0,05), demonstrando melhor resultado no nÃvel 33% de substituiÃÃo. As variÃveis odor caracterÃstico, odor estranho, sabor caracterÃstico, sabor estranho, sabor ranÃoso, sabor adocicado e aceitaÃÃo global, foram influenciados (P<0,05), com mÃdias de 3,24, 2,88, 5,20, 3,86, 3,49, 4,10 e 4,36% respectivamente. Os resultados encontrados indicam que o AEFM, apesar de ocasionar reduÃÃo da digestibilidade dos nutrientes, pode ser utilizado na substituiÃÃo do farelo de soja em dieta de cabras leiteiras sem reduÃÃes no consumo de nutrientes, sem afetar a produÃÃo e qualidade do leite, e sem proporcionar qualquer dano à saÃde animal.
This study was conducted to evaluate the performance and quality of dairy goats fed milk diets containing extruded food-based castor meal (EFCM) in dairy goats. Four groups of five female Saanen goats, were fed with diets with different levels of soybean meal replacement by ECCM: 0, 33, 67 and 100%, for 34 days. There was no treatment effect (P>0.05) on the evaluated nutrients intake: dry matter (g/d, %BW and g/kg BW0.75), crude protein (g/d and g/kg BW0.75), extract ether (g/d and g/kg BW0.75), neutral detergent fiber (g/d, %BW and g/kg BW0.75), non-fibrous carbohydrates (g/kg BW0.75) and total carbohydrates (g/d and g/kg BW0.75). The non-fibrous carbohydrate intake (g / d) was affected (P <0.05), presenting a positive linear relashionship with inclusion level of EFCM. Was no influence of treatment on the DMD, OMD, CPD, NDFD DEE and nutrients, causing linear effect (P <0.05). As well as in DCNF that showed a quadratic effect (P <0.05). There was no influence of the treatments (P> 0.05) on the consumed nitrogen parameters, nitrogen excreted in the urine nitrogen excreted in milk, nitrogen balance, the total nitrogen excretion and basal endogenous nitrogen. It was observed that the values found for fecal nitrogen, were affected (P <0.05). The parameters of the physical and chemical composition of milk, it was observed that there was no effect (P> 0.05) on milk production (PM), in gross composition of milk protein (PMC) and milk fat (MF).The average values of milk urea nitrogen (MUN) were affected (P <0.05) compared with control diet. There was no effect (P> 0.05) on lactose (LAC), and total solids (TS).For dry extract variables defatted and yield of cheese, there was influence (P<0.05), averaging 76,42g.kg-1 and 22.25%. The concentration of the butyric acid content in fatty acids (C4: 0) and caprylic (C8: 0) were affected (P <0.05) when compared to the control treatment. There was no effect (P> 0.05) on the levels of saturated fatty acids (SFA), unsaturated fatty acid (UFA), polyunsaturated fatty acids (PUFA). For the atherogenicity index (IA) showed a significant effect (P <0.05), demonstrating best results in 33% replacement level. The variables characteristic odor, strange odor, characteristic taste, strange taste, rancid flavor, sweet taste and overall acceptability were affected (P<0.05), with averages of 3.24, 2.88, 5.20, 3, 86, 3.49, 4.10 and 4.36% respectively. The results indicate that the EFCM, despite causing a reduction in the digestibility of nutrients, can be used in replacement of soybean meal in diets of dairy goats without reductions in nutrient intake without affecting the production and quality of milk, and without providing any damage to animal health.

These days, milk substitute products are getting more popular and exist together with milk on the market. These substitute products are appreciated by consumers due to animal welfare, environmental or health related reasons. The purpose of the investigation was to make assumptions about the future situation of farmers and which demographic, personal, sociological, cultural and psychological determinants have an impact on Swedish consumers purchasing substitute products. The proposed methodology to reveal the impact of those factors was a qualitative research. Ten semi-structured interviews with residents of Västra Götaland, aimed to gain a deeper and better understanding of the reasons for consumption of milk substitute products, were conducted in total. The existing theory and scientific articles about demographic, personal, sociological, cultural and psychological determinants of consumer behavior, in terms of food choice and consumption, were used to create an interview guide and also to compare the collected primary data in the end. Participants were asked questions regarding their demography, lifestyle, awareness and perception of milk substitute products and other reasons for their consumption of milk substitutes. The findings revealed that demographic factors such as age and gender seemed to have an impact on the consumer behavior. Moreover, personal and psychological factors were revealed to have a significant impact on the consumption behavior. In particular lifestyle, perception, attitudes and motivations, knowledge and learning had a significant influence on Swedish consumers and their food consumption behavior. Regarding sociological factors it was discovered that friends had a significant influence on food consumption. Cultural determinants were also important to consider. However, they did not have a significant influence on the participants. The findings also revealed that health and animal welfare were the main reasons for changing the consumption. Interestingly, no participant started to consume these products due to environmental reasons in the beginning. The strong competition of milk and milk substitute products on the market is most likely to continue. The future situation for farmers will look different and might get more critical as milk consumption in Sweden could change. This small scale research does not make it possible to generalize the revealed findings. Nevertheless, this qualitative investigation provided the basis for future research in the field of consumer behavior towards substitute products.

Residual value is defined as the price for which a used piece of equipment can be sold in the market at a particular time. It is an important element of the owning costs of equipment and needs to be estimated by equipment managers for making investment decisions. The purpose of this study is to gain insights into the residual value of selected groups of heavy construction equipment and to develop a mathematical model for its prediction. Auction sales data were collected from two online databases. Manufacturer publications and an online source provided size parameters and manufacturers suggested retail prices matching the auction records. Macroeconomic indicator values were collected from a variety of sources, including government agencies. The data were brought into the same electronic format and were matched by model name and calendar date, respectively. Data from auctions in the U.S. and in Canada were considered for this study. Equipment from four principal manufacturers of up to 15 years of age at the time of sale was included. A total of 35,542 entries were grouped into 11 different equipment types and 28 categories by size as measured by horse power, standard operating weight, or bucket volume. Equipment types considered were track and wheel excavators, wheel and track loaders, backhoe loaders, integrated toolcarriers, rigid frame and articulated trucks, track dozers, motor graders, and wheel tractor scrapers. Multiple linear regression analyses of the 28 datasets were carried out after outliers had been deleted. Explanatory variables for the regression model were age in years, the indicator variables manufacturer, condition rating, and geographic region, and selected macroeconomic indicators. The response variable was residual value percent, defined as auction price divided by manufacturers suggested retail price. Different first, second, and third-order polynomial models and exponential and logarithmic models of age were examined. A second-order polynomial was selected from these functional forms based on the adjusted coefficient of determination. Coefficients for the 28 models and related statistics were tabulated. A spreadsheet tool incorporating the final regression model and its coefficients was developed. It allows performing the residual value prediction in an interactive and intuitive manner.
Ph. D.

The purpose of this study was to develop a short, easy procedure to measure five major proteins in milk and to detect concentrations of added protein to dairy products. Combinations of casein or whey protein with nonfat-dry milk were made with concentration ratios from 0:10 to 10:0. Similar mixtures of defatted goat milk with defatted cow milk were prepared. Samples were hydrolyzed in 6 N HCl at 145°C for 4 h and analyzed for amino acid composition. Multiple regression equations were derived to estimate the relative content of whey protein or casein added to nonfat-dry milk and goat milk added to cow milk employing amino acid profiles of whey protein, casein, nonfat-dry milk, goat milk and cow milk. Correlation coefficient values were all greater than .99. Measuring individual concentrations of milk proteins required separating casein and why proteins by reverse phase high performance liquid chromatography on a C3 column. αs-, β-, and κ-casein were separated after dissociating casein micelles with mercaptoethanol and urea. A 40:60 to 0:100 gradient of .15 M sodium chloride/triethylamine (pH 2.5) and 40% acetonitrile was used. Whey proteins, α-lactalbumin and β-lactoglobulin were separated with a 95:5 to 0:100 gradient of .15 M sodium chloride (pH 2.4) and acetonitrile. Eluted proteins were collected from the column, analyzed for purity by electrophoresis, and hydrolyzed in 6 N HCl at 145°C for 4 h. Purified proteins and mixtures of purified proteins were analyzed for amino acid composition. Estimates of individual protein concentrations in mixtures were made by solving simultaneous equations based on amino acid composition using a tektronix 4052 computer.

Mestrado em Bioquímica - Bioquímica Alimentar
The presented work describes the inclusion of the flavonoid quercetin into β and γ cyclodextrins and the subsequent incorporation of such complexes into a dairy product — fresh cheese. The characterization of the complexes was made using various techniques, and antioxidant assays were also performed to assess their antioxidant and anti-lipid peroxidation capacity in comparison to quercetin. The incorporation of the complexes in fresh cheese resulted in the modification of some of the characteristics of the food product, having these also presented promising antioxidant capacity.
O trabalho apresentado descreve a inclusão do flavonóide quercetina nas ciclodextrinas β e γ, com posterior incorporação dos complexos em laticínios, nomeadamente queijo fresco. A caracterização dos complexos de inclusão foi feita utilizando várias técnicas, tendo sido também realizados ensaios antioxidantes para avaliar a sua capacidade antioxidante e de anti-peroxidação lipídica, em comparação com a quercetina. A incorporação dos complexos no queijo fresco resultou na modificação de algumas características do produto alimentar, tendo estes complexos também apresentado uma promissora capacidade antioxidante.

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Different objectives were evaluated with different supplementation strategies procedures in beef cattle in two distinct projects. In Experiment 1, Thirty-two multiparous Angus beef cows in moderate body condition score (3 in a 1 to 5 scale) received supplementary feeding during early lactation, for a short period (35d), to determine the effect on milk production and composition and cow and calf performances. Both groups were maintained in grazing native condition during the supplemental period. Milk composition and yield, cow and calf performance were evaluated at 0d (initial); 14d (middle) and 35d (final) of supplementation period. There was no effect (P>0.05) of supplementation on milk production or any milk component, and on calves performance. Milk composition was different between periods, where fat concentration was higher at the middle of supplementation and lactose was higher at the end of this period. Supplemented cows had a higher (P=0.03) average daily gain at the final supplemental period than cows in control group. In conclusion, beef cows in moderate body condition score may gain weight during the lactation period responding to supplementation in a short period, without any influence on milk production, composition in the calf performance. In Experiment 2, Four beef heifers fitted with ruminal and duodenal cannulas were used in a 5 x 4 incomplete Latin square experiment to determine the dietary replacement value of camelina meal for soybean meal in forage-based diets of beef cattle. Heifers were fed bromegrass hay (7.1% CP, 52.2% NDF on an OM basis) and the diet was formulated to meet the RDP requirement for the hay offered with supplemental soybean meal as a protein supplement. In an isonitrogenous basis, the treatments aimed to replace the soybean in five different levels (0, 25, 50, 75 and 100%) using camelina meal as a protein source. There was no difference (P>0.05) of increase levels of camelina meal addition as a replacement of soybean meal on OM, NDF and N digestibility. Consequently, we could not find any difference (P>0.05) on the patterns of ruminal fermentation end-products as well. The lack of differences in site and extent of digestion among dietary treatments is consistent with similar (P>0.05) performance for the heifers. Therefore, camelina meal seems to be a suitable alternative for supplementary soybean meal in forage-based diets consumed by beef cattle.
Com diferentes objetivos foram avaliados diferentes métodos estratégicos de suplementação para bovinos de corte, bem como as potencialidades de utilização dentro dos diferentes sistemas de produção em dois distintos projetos. No Experimento 1, Trinta e duas vacas Angus multíparas em escore de condição corporal moderado (3 em escala de 1 a 5) receberam suplementação alimentar no início de lactação, por um período curto (35 dias), para determinar o efeito sobre a produção e composição do leite e o desemenho de vacas e bezerros. A avaliação da produção de leite, desempenho ponderal de vacas e bezerros foram controlados no dia 0 (inicio); 14 (meio) e 35 (final) do período de suplementação. Não houve efeito (P>0,05) da suplementação na produção ou de qualquer componente do leite em ambos os grupos, bem como sobre o desempenho de bezerros. Composição do leite foi diferente entre os períodos, onde a gordura foi maior no meio da suplementação e lactose foi maior no final deste período. Vacas suplementadas apresentaram maior (P=0,03) ganho de peso médio diário no período final da suplementação. Vacas de corte podem ganhar peso durante o período de lactação em resposta a suplementação em um curto período, sem qualquer influência sobre a produção e composição do leite ou no desempenho dos bezerros. No Experimento 2, quatro novilhas de corte canuladas no rumen e duodeno foram utilizadas em um desenho experimental 5x4 Quadrado Latino incompleto, para determinar a utilização do farelo de camelina como um suplemento proteico em reposição ao farelo de soja. Os animais foram alimentados com feno (7,1% de PB, 52,2% de FDN em base de MO) e a dieta foi formulada para atender a exigência PDR para o feno oferecido com farelo de soja como suplemento proteico. Em uma base isoprotéica, os tratamentos foram calculados para substituir o farelo de soja em cinco diferentes níveis (0, 25, 50, 75 e 100%). Não foi encontrado efeito (P>0,05) da reposição do farelo de soja por farelo de camelina na digestão da matéria orgânica, fibra e digestibilidade do nitrogênio, bem como não hove diferenças (P>0,05) nos padrões de fermentação ruminal, refletindo em um desempenho ponderal semelhante (P>0,05). Sendo assim, o farelo de camelina parece ser uma adequada alternativa ao farelo de soja como um suplemento proteíco em dietas a base de forragem para bovinos de corte.

Today approximately 10 % of fermented milk products stick to the packaging material inner surface, and therefore it is not possible to pour all of the dairy product from the package. This is both an economical and environmental issue. The product loss is expensive for consumer and makes recycling of package less effective. As they do not yet exist the development of packaging materials to which fermented milk products stick less, it would make it possible to both save money and protect our environment. The aim of this work was to provide knowledge and understanding of the important factors involved in the phenomenon when fermented milk products adhere to the inner surface of a packaging material. Studies were done on materials having different surface properties, such as polarity and relative oxidation. They were incubated in fermented milk and other dairy products varying in fat concentration and protein type up to 168 h. The systems were investigated gravimetrically, with Fourier Transform Infra Red/Attenuated Total Reflectance Spectroscopy, Scanning Electron Microscopy and Contact Angle measurements. Fermented milk contains amphiphilic components and therefore can interact both with polar and non-polar surfaces, such that the relative oxidation of the surface does not contribute to the adhesion. The adhesion of fermented milk is an equilibrium reaction, which depend on the fat concentration before equilibrium as well as the protein concentration after equilibrium. The adhesion seems to follows the Vroman effect, with smaller molecules associating faster and thereby adhering to the surface initially, but are displaced by larger molecules that associates slower as times passes.

In this paper, we estimate dynamic versions of the Almost Ideal Demand System and the Linear Expenditure System in order to obtain an estimate of the demand elasticity for milk in British Columbia. This parameter has, to our knowledge, never been estimated for one province, but given the ongoning interest by the B.C. dairy industry in obtaining a larger allocation of Market Share Quota (MSQ), which is now allocated as a function of fluid milk consumption, it is timely to estimate the elasticity of demand for milk in British Columbia. Many have argued that the retail price of milk in B.C. is too high, especially when compared to prices in other western provinces, as well as the neighbouring State of Washington. The argument is that significant increases in consumption, and thereby increased allocation of MSQ could be achieved through decreases in prices. However, this depends upon the elasticity of demand which we herein estimate. Our estimate of the elasticity of demand for milk in British Columbia is -0.33, as estimated from the dynamic Almost Ideal System, and -0.40 from the dynamic Linear Expenditure System. We note that the dynamic Linear Expenditure System estimated in this study was statistically significant and met all theoretical restrictions, in particular quasi-concavity of the utility function at each observation point. We note, however, that this elasticity estimate may be interpreted as a short run estimate owing to our limited time frame for analysis. Clearly, with an elasticity estimate in the order of -0.40, "significant" increases in consumption cannot be achieved solely through decreases in prices. This paper, however, does more than simply relay elasticity estimates, for it also provides tips and techniques for estimating demand systems such as those estimated in this paper. These strategies are typically not found in textbooks or journal articles, and as such can be of great use to those estimating demand systems for the first time. In addition, this study makes use of a regional data source that has previously been unavailable to applied economists. Those who have attempted to estimate the demand for milk regionally have found that Statistics Canada does not publish regional consumption figures for most commodities. This is particularly true for the consumption of beverages in British Columbia. The data for this study were obtained privately and statistically represent bi-monthly sales of beverages in British Columbia. Thus, this paper is the first to estimate the demand for milk in British Columbia by using a demand systems approach employing data obtained from a private source (i.e. not Statistics Canada or other public sector organisations).
Land and Food Systems, Faculty of
Graduate

Milk and dairy products are important source of bioactive compounds useful to satisfy the nutritional and physiological needs of any newborns of mammalian species and useful to guarantee adequate growth and development of infants as well as provide a complete nourishment of adults. Physico-chemical, nutritional and organoleptic properties of the main constituents and the “minor” components have a crucial role in the quality of milk and milk products. Although in the past decades dietary milk fat was often regarded as harmful for the human health, recent researches suggest that milk contains specific fatty acids with nutritional and physiological health benefits. For these reasons, a major attention is given to the quantity and quality of total fat intake. In the recent years, as a result of the new concept of multifunctional agriculture and the changing behaviours about diet, consumer demands in favor of high-quality, security and safety dairy products are increased. Moreover, milk proteins and milk-derived bioactive peptides are recognized to have a high nutritive value, several health-promoting functional activities and excellent technological properties. Accordingly, growing interest in the development of functional dairy products and preparation of infant formulae for babies who cannot be breast-fed, has been give in order to meet the specific consumer’s requests. This manuscript presents the main results obtained during my PhD research aimed to evaluate the main bioactive lipids and proteins in milk and dairy products using innovative analytical techniques. The experimental section of this manuscript is divided in two sections where are reported the main results obtained during my research activities on dairy products and human milks in order to characterize their bioactive compounds for functional food applications.

Milk and dairy products are important source of bioactive compounds useful to satisfy the nutritional and physiological needs of any newborns of mammalian species and useful to guarantee adequate growth and development of infants as well as provide a complete nourishment of adults. Physico-chemical, nutritional and organoleptic properties of the main constituents and the “minor” components have a crucial role in the quality of milk and milk products. Although in the past decades dietary milk fat was often regarded as harmful for the human health, recent researches suggest that milk contains specific fatty acids with nutritional and physiological health benefits. For these reasons, a major attention is given to the quantity and quality of total fat intake. In the recent years, as a result of the new concept of multifunctional agriculture and the changing behaviours about diet, consumer demands in favor of high-quality, security and safety dairy products are increased. Moreover, milk proteins and milk-derived bioactive peptides are recognized to have a high nutritive value, several health-promoting functional activities and excellent technological properties. Accordingly, growing interest in the development of functional dairy products and preparation of infant formulae for babies who cannot be breast-fed, has been give in order to meet the specific consumer’s requests. This manuscript presents the main results obtained during my PhD research aimed to evaluate the main bioactive lipids and proteins in milk and dairy products using innovative analytical techniques. The experimental section of this manuscript is divided in two sections where are reported the main results obtained during my research activities on dairy products and human milks in order to characterize their bioactive compounds for functional food applications.

Entre os anos de 2007 e 2009, no nordeste do Rio Grande do Sul, foi conduzido um estudo para avaliar a ocorrência de leite instável não ácido, fatores que afetam a estabilidade do leite bovino e a relação entre o teste do álcool e o teste de tempo de coagulação do leite. Fez-se um questionário para a tipificação das propriedades, um levantamento mensal do leite de 50 propriedades, e se analisou a acidez, coagulação na fervura e no álcool e tempo de coagulação no tanque, além da composição química, células somáticas e contagem bacteriana. Posteriormente, foi realizado um experimento avaliando dietas com três proporções de concentrado (35, 45 e 55%), por 56 dias, avaliando o número de dias em lactação, produção leiteira, peso, condição corporal, características físico-química do leite, pH ruminal e da urina e composição química do sangue. Complementarmente foram realizados quatro protocolos experimentais para avaliar o efeito da temperatura sobre o teste do álcool, o efeito do citrato sobre a estabilidade do leite, o efeito do uso de capilares de diferentes tamanhos sobre o resultado de tempo de coagulação e o uso de diferentes metodologias analíticas para determinação de lactose no leite. A análise estatística dos dados foi efetuada com o programa SAS (2001), avaliando a frequência de ocorrência de fatores (Proc FREQ), correlação (Proc CORR), variância (Proc GLM) e regressão (Proc REG), sendo que no experimento com animais as médias foram ajustadas utilizando dias em lactação, e os valores iniciais de cada atributo como co-variáveis. Foram observados elevada incidência de LINA, CCS e CBT, pouca interferência da dieta na ocorrência de LINA e na alteração da composição do leite e baixa correlação entre o teste do álcool e o tempo de coagulação no tanque. Não houve relação entre o teste da fervura e os testes do álcool e do tempo de coagulação. O citrato melhorou a estabilidade do leite medida no teste do álcool e no tempo de coagulação. A temperatura do leite (4 x 20°C) não interferiu no resultado do teste do álcool. As dimensões dos capilares de teste do tempo de coagulação modificam os valores obtidos, podendo prejudicar a comparação entre diferentes laboratórios. Entre os fatores testados, os que atuaram sobre a estabilidade do leite no teste do álcool foram: a concentração inicial de álcool capaz de induzir a coagulação, a concentração de cátions divalentes em relação aos monovalentes e o teor de sódio do leite. Em relação ao teste do tempo de coagulação, apenas o seu valor inicial foi significativo. Conclui-se que a ocorrência da instabilidade do leite é elevada, a composição mineral do leite foi a que exerceu maior influência sobre os resultados no teste do álcool, não foram detectados fatores que influenciaram o teste do tempo de coagulação nem o da fervura. Não se pode ainda recomendar outro teste para substituir o teste do álcool.
Between 2007 and 2009 in the Northeastern Rio Grande do Sul, a study was conducted aiming to evaluate the occurrence of unstable non-acid milk, the factors affecting the stability of bovine milk and the degree of relationship between test results and alcohol test coagulation time of milk. Was carried out initially, a questionnaire for the characterization of the properties, then a monthly survey of milk from 50 properties, and examined the acidity (acidity and pH), coagulation test and the boiling alcohol and clotting time in tank, and chemical composition, somatic cell and bacterial count. Later we performed an experiment on animals, which were fed with three different proportions of concentrate (35, 45 and 55%) for 56 days and were evaluated the number of days in milk, milk production, weight, body condition, features physical chemistry of milk, pH and composition of urine and blood chemistry. In addition were performed four experimental protocols to evaluate the effect of temperature on the alcohol test, the effect of citrate on the stability of milk, the effect of using capillaries of different sizes on the results of clotting time and the use of different analytical methodologies for determination of lactose in milk. The statistical analysis was performed with SAS software (2001), evaluating the occurrence of factors (Proc FREQ), correlation (CORR), variance (Proc GLM) and regression (Proc REG), and the experiment animals the means were adjusted using days in milk, and the initial values of each attribute as covariates. We observed high levels of incidence of LINA, CCS and CBT, little interference from the diet in the occurrence of LINA and change the composition of milk and low correlation between the alcohol and the clotting time in the tank. There was no relationship between the boiling test and tests for alcohol and clotting time. Citrate exerted positive action on the stability of milk as the test of alcohol and the clotting time. The temperature of milk during the test (4 x 20 ° C) had no effect on the test result of alcohol. The dimensions of the capillary test of clotting time modify the values and may undermine the comparison between different laboratories. Among the factors tested, acted on the stability of milk alcohol test were: the initial concentration of alcohol to induce coagulation, the concentration of divalent cations compared to monovalent and sodium content of milk. For the test of clotting time, only the initial value was significant. It is concluded that the occurrence of instability of the milk is high, the factors measured, the mineral composition of milk that was the greatest influence on the results in the alcohol, but not detected factors influencing the test of clotting time or to the boil. You can not even recommend another test to replace the alcohol test.

Com o objetivo de determinar a influência dos sistemas de produção e de alimentação sobre as características do leite, dados coletados de produtores de leite do sul do Brasil e de experimentos sobre níveis de restrição alimentar e de atendimento das exigências energéticas de vacas em lactação foram submetidos à análise de fatores principais, de correlação e médias canônicas, agrupamento e comparação de médias dos grupos. Os atributos estudados comuns em todos os sistemas foram produção leiteira diária, componentes lácteos, estabilidade do leite, peso corporal e escore de condição corporal. Na análise dos sistemas de produção, três grupos de produtores foram formados pela análise de agrupamento, com características de sistemas especializados, semi-especializados e não especializados em ambas as regiões avaliadas. Grupos de produtores especializados produziam leite em conformidade com as especificações da Instrução Normativa Nº 62. Enquanto que para os produtores da região sul do Rio Grande do Sul, as estratégias de alimentação foram determinantes para distinção entre os grupos de produtores, no extremo oeste de Santa Catarina a estrutura das propriedades foi mais determinante. Níveis de restrição severos (40 e 50%) alteraram significativamente a produção leiteira diária, os teores de proteína e lactose e a estabilidade do leite. O atendimento das exigências energéticas para vacas em lactação possui uma relação direta com a produção diária de leite, com o teor da lactose e com a estabilidade do leite. A produção leiteira, os componentes lácteos e a estabilidade do leite diferenciam-se entre os sistemas de produção e alimentação.
Aiming to determine the influence of production and feeding systems on milk characteristics, data collected from dairy producers in southern Brazil and experiments on levels of feed restriction and attendance of the energy requirements of lactating cows were subjected to principal factor, correlation and means canonical, cluster analysis and comparison of means between groups. The variables common to all systems were daily milk production, milk components contents, ethanol stability, body weight and body condition score. In the analysis of production systems, three producers groups were formed by cluster analysis, with characteristics of specialized, semi-specialized and unspecialized systems in both regions evaluated. Groups of specialized dairy farmers produced milk in accordance with Normative Instruction Nº 62. While for the producers in southern Rio Grande do Sul, the feeding strategies were crucial to distinguish groups, at the far west of Santa Catarina structure of the properties was more important. Severe feed restriction levels (40 and 50%) altered significantly the daily milk yield, protein and lactose contents and ethanol stability. Attendance of the energy requirements for lactating cows showed a direct relationship with the daily milk production, content of lactose and milk stability. Milk production, milk components and milk stability are different between production and feeding systems.

ABSTRACT Within the complex bacterial community of traditional raw milk cheeses, lactic acid bacteria (LAB), naturally present in the milk as adventitious contaminants, play the key role in the cheese manufacture and ripening process through their acidifying, proteolytic and flavouring activities. Moreover, LAB contribute considerably to the microbial safety, since they produce organic acids and bacteriocins that extend shelf-lives of raw milk products. Numerous LAB genera and species such as Lactobacillus, Lactococcus, Streptococcus, Leuconostoc and Enterococcus are involved in these metabolic activities. This natural microbial biodiversity can be considered a heritage which has to be protected and preserved, since alterations in the composition of the beneficial autochthonous microbiota is of critical importance in maintaining the peculiar features of the traditional raw milk products. On the contrary, LAB may have also negative traits, such as the ability to produce toxic biogenic amines, possession of transmittable antibiotic resistance genes, and the potential for expression of putative virulence factors. Dairy safety aspects should include careful examination of these harmful features. Therefore, the study of micro-organisms at species and strain level and the monitor of their dynamics in the microbial community throughout cheese manufacture and ripening is helpful to improve the quality and safety of the final product. Classical microbiological and molecular techniques have been widely used to investigate the dairy biodiversity and to achieve the characterization of bacterial species present in a complex microbial dairy ecosystem, highlighting the advantages and the limitations of both methods. The aims of PhD thesis were: I) to apply a polyphasic approach based on different phenotypic and molecular techniques for the characterization of the LAB isolated from dairy products collected throughout the technological process of an artisanal raw milk cheese, such as “Formagèla Valseriana”; II) to evaluate the application of total microbial DNA extracted directly from dairy products as template in PCR 16S-23S rRNA region spacer analysis (RSA-PCR) in order to achieve a rapid knowledge about their microbial communities, bypassing the previous step of isolation in pure culture; III) to investigate the influence of equipment (thermocycler) and reagents (Taq polymerase) on results obtained from RSA analysis; IV) to explore the functional and safety aspects of E. faecalis strains isolated from dairy products collected in different North Italy regions through the study of their biodiversity, bacteriocin, volatic organic compounds and biogenic amines production, virulence factors and antibiotic resistance. Firstly, evolution of bacterial groups during the cheese-making process of “Formagèla Valseriana” was revealed by viable counting of LAB and non-LAB micro-organisms. A total of 143 presumptive LAB strains from milk culture, curd and cheese samples were randomly selected from agar plates and subjected to morphological and phenotypic characterization (microscopic examination, Gram staining, catalase test, growth at 15 and 45 °C, CO2 production from glucose) and molecular identification. To investigate LAB biodiversity, the taxonomic position of the isolates was established through RSA-PCR combined with a species-specific PCR assay. Strains characterized by atypical classes of spacer were identified by partial 16S rRNA sequencing. Random amplified polymorphic DNA analysis (RAPD-PCR) was carried out to explore the genetic diversity of LAB isolates. In addition, this study was intended to evaluate the application of microbial DNA extracted directly from dairy products as template in RSA-PCR in order to achieve a rapid knowledge about their microbial communities, bypassing the previous step of isolation in pure culture. As expected in raw milk cheeses, LAB (i.e. lactobacilli, lactococci and enterococci) were quantitatively the dominant group for all samples. The combination of various molecular procedures allowed many species to be detected. In particular, milk culture showed a prevalence of Streptococcus thermophilus, whereas the most detected LAB in curd belonged to the species Lactococcus lactis ss lactis, Lc. garvieae and Enterococcus durans. E. durans was the species most frequently isolated from cheese samples, even if several species (E. faecalis, E. gilvus, E. italicus, Lb. paracasei ss paracasei, St. bovis, Lb. plantarum, Lb. coryniformis and Ln. mesenteroides), which are indicative of biological richness, were also present. RAPD-PCR revealed a high biodiversity at species level, but it also showed the presence of significant genetic variability among the isolates belonging to the same species. RSA, using as template DNA extracted directly from milk culture, did not prove to be a suitable method for discrimination of microbial species in a complex matrix, since when microbial community was very heterogeneous and rich, it was difficult discerning LAB species or genera. Actually, the band of S. thermophilus represents the only one that could be frequently identified. The 143 LAB strains were then screened for their inhibitory activity against Listeria monocytogenes and Staphylococcus aureus and for their acidifying activity. Seven and six strains, mainly belonging to the Enterococcus genus, exhibited antagonistic activity against L. monocytogenes and S. aureus, respectively. With regard to acidifying activity, the majority of isolates (88.8%) were found to be low acidifying isolates, causing a pH decrease lower than 1.5 pH units, whereas only 16 strains were classified as medium acidifying isolates and could be considered the fastest acidifying strains. Yet, after 24 h 74.1% of the isolates showed a medium acidifying ability and 9.1% were classified as high acidifying strains. As revealed by screening the microbial population of “Formagèla Valseriana”, the Enterococcus genus is one of the most prevalent within dairy microbial community. However, enterococci are ascribed the most controversial nature, presenting both beneficial and negative features. They represent important nosocomial pathogens, but are also recognized to produce bacteriocin with antibacterial activity and to enhance flavour and aroma development in cheese. For this reason, 40 Enterococcus faecalis strains isolated from raw milk products (milk, curd and cheese) collected throughout the technological process of various North-west Italian traditional cheeses (Aosta Valley, Piedmont and Lombardy) over a 13 year period (1997-2009) were examined. The genetic biodiversity of E. faecalis isolates was assessed through RAPD-PCR and repetitive extragenic palindromic PCR (rep-PCR). Phenotypic and molecular protocols were applied in order to investigate the incidence of antibiotic resistance and virulence factors among strains. They were examined for their antimicrobial activity against 18 foodborne spoilage and pathogenic bacteria. Investigation was also made to identify their bacteriocinogenic potential by searching for bacteriocin-encoding genes (enterocin A, enterocin B, bacteriocin 31, enterocin P, enterocin Q, enterocin L50A-B, mundticin KS, enterocin CRL35, enterocin AS-48, and enterocin 1071A-B). In addition, they were inoculated in milk and submitted to head-space solid-phase-micro- extraction gas chromatography-mass spectrometry analysis in order to study their capability for production of volatile organic compounds (VOCs). Resistance to streptomycin (50%), quinupristin-dalfopristin (32.5%), tetracycline (25%), rifampicin (7.5%), chloramphenicol (5%) and erythromycin (2.5%) were evidenced. Ampicillin, ciprofloxacin, levofloxacin, mupirocin, nitrofurantoin, penicillin G and vancomycin were revealed effective antimicrobials against all the strains considered. Tetracycline resistance was also confirmed by detection of tet(M), tet(K), tet(L), tet(S) and transmissibility of resistance by integrase gene (int) of the Tn916/Tn1545 family of transposons. The high incidence of tet(M) gene, found in 90% of the isolates, doesn’t correlate with their phenotypic expression, thus highlighting the presence of silent genes. The phenotypic assay of haemolytic activity showed positive results (β-haemolysis) only in 2 strains. Among the 7 virulence determinants tested, only gel, asa1, esp and efaA genes were harboured. None other gene encoding for either different virulence factors (cylA, hyl, ace), or amino-acid decarbolylase activity (hdc, tdc, odc) was detected. Our results suggest that dairy enterococci don’t represent the major potential reservoir for the spread of the investigated detrimental traits in contrast to other strains of different origin. Considering their antimicrobial activity, all the E. faecalis tested were active against at least 1 of the 18 indicator strains. Remarkable inhibitory effects against harmful or detrimental microbial species, including Bacillus cereus (44.7% of strains), Escherichia coli (17.5%), L. monocytogenes (15%), St. aureus (2.6%), and Clostridium sporogenes (21.1%), was detected. Moderate antagonism towards LAB (65.8% of strains), especially Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus helveticus, was found, too. However, 31.6% of E. faecalis strains were reported as ideal preservatives. Of the 10 enterocin structural genes explored, only gene for enterocin AS-48 was identified, suggesting that the antimicrobial activity of the phenotypically positive isolates should necessarily be due to another enterogenic or non-enterogenic compound. A significant genetic variability was pointed out, but it was no possible to link the enterocin phenotypes and genotypes with the strain origin. No relation with the geographical origin or the period in which the strains were isolated was also found with regard to the VOCs production and very different enzymatic activities among strains was detected. The major volatile compounds produced were: ethanol, diacetyl, acetoin, acetic and benzoic acids. The results of the present study suggested that a polyphasic approach, combining different phenotypical and genotypical methods, may represent an essential tool to obtain a more effective, accurate and exhaustive investigation of the microbial typing. Finally, even if RSA-PCR was proven to be a rapid, reliable and cost-effective alternative to other PCR methods for the microbial identification and typing, the possibility to compare RSA-PCR results obtained with different thermal cyclers and Taq DNA polymerases has not been investigated effectively. Four models of thermal cyclers of 3 different commercial brands and 4 brands of Taq DNA polymerase were evaluated for their effects on the reproducibility of the RSA-PCR. Five reference LAB strains (St. thermophilus, Lb. helveticus, Lb. delbrueckii subsp. lactis, Lb. delbrueckii subsp. bulgaricus and Lb. fermentum) and a DNA mixture, obtained combining together the DNAs extracted from each reference strain in the same ratio, were used in the experiment. A wide variety of RSA-PCR profiles in terms of band number and size were observed in relation to thermal cycler and Taq DNA polymerase tested, highlighting the relevant influence of these two variables on RSA-PCR reproducibility. It is therefore recommended to choose, within each laboratory, appropriate operating procedures in accordance with one’s equipment and reagents.

碩士
銘傳大學
企業管理學系碩士在職專班
101
Taiwan''s fresh milk market is mainly sold in refrigerated distribution of milk and flavored milk, and market share rate of the top three companies are Wei-Chuan Foods Co., Ltd, Kuang-Chuan Dairy Co., Ltd and Uni-President Enterprises Co., Ltd. In recent years, consumers expect more healthy purposes for milk beverages, so the sales volume of the functional dairy product which adds vitamins, calcium or increases nutrition absorption ability in milk have increased significantly. Kuang-Chuan Dairy Co., Ltd. main business scope is milk beverage formulation development, production and selling, although milk and flavored dairy products have been well-known domestic brands, but for functional milk drinks not widely recognized by consumers. Therefore, this study will focus on the Kuang-Chuan company''s newly developed lactose free functional milk product- Kuang-Chuan Healthy Benefits Milk, using the STP marketing theory to analysis Kuang-Chuan Company''s products market positioning, establish marketing strategies, and strengthen the impression of healthy products to enhance consumers'' purchasing intention. The results showed that major consumer markets group of Kuang-Chuan Healthy Benefits Milk is female office workers whose age range is 30-40 years old, product tasted similar to fresh milk, the price can be higher than other branded products but less than $NT 5, the majority of sales channel is convenience store, product promotion methods contains tasting, take the gift, television advertising and brand endorsement by female nutritionist, despite its established brand marketing strategy has been quite clear, but not with a direct interaction of the consumer groups. Therefore, this study suggests that Kuang-Chuan Company to maintain the original marketing strategy, additionally taking the advantages of Facebook social networking platform because of its rapid flow characteristics on advertising and share consumers drinking experience, thereby increasing the interaction of community platform with fans and potential customers, in order to achieve the target of increasing sales.