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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Comparison of Mojonnier and Babcock fat tests on cheese and whey

al-Noorachi, Akram A. F. January 1963 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1963. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 30-32).
2

Produção e aplicação de hidrolisado de proteínas do soro de queijo bovino no preparado de suplemento nutricional : minimização da sarcopenia em ratos idosos /

Marques, Daniela Parreira. January 2009 (has links)
Orientador: Rubens Monti / Banca: Thais Borges Cesar / Banca: João Atílio Jorge / Banca: Rosa dos Prazeres Melo Furriel Inocentes / Banca: Reinaldo Marchetto / Resumo: Os hidrolisados de proteínas do soro de queijo vêm sendo amplamente utilizados para diversos fins. Dependendo das enzimas utilizadas e meio de reação, podemos obter hidrolisados com diferentes características. O intuito do presente trabalho foi hidrolisar as proteínas do soro de queijo bovino de diferentes maneiras, variando-se a temperatura de reação e modo de adição das enzimas, a fim de se obter hidrolisados com diferentes graus de hidrólise para posterior aplicação em ensaios animais. Os hidrolisados escolhidos para aplicação nos ensaios biológicos foram obtidos pela ação das enzimas pepsina, tripsina, quimotripsina e carboxipeptidase a 50ºC. Dois hidrolisados diferentes foram preparados: um com maior quantidade de pequenos peptídeos (oligo, di e tripeptídeos) e outro com maior quantidade de aminoácidos livres. O soro sem hidrólise também foi utilizado como suplementação para um outro grupo de animais. A intenção foi testar os dois diferentes hidrolisados e o soro sem hidrólise como suplemento para ratos idosos, visando a minimização da sarcopenia. Diversos estudos apontam que fórmulas contendo oligopeptídeos, especialmente di- e tripeptídeos, possuem maior valor nutricional do que uma mistura equivalente de aminoácidos livres ou proteínas intactas. Tomando-se como base essa informação, delineou-se a pesquisa esperando-se que, o grupo suplementado com as proteínas parcialmente hidrolisadas obtivesse um melhor desempenho na minimização da sarcopenia. Todos os 3 grupos suplementados obtiveram aumento na massa muscular e óssea diferindo significativamente em relação ao controle (não suplementado) porem, o que apresentou efeitos mais positivos na minimização da sarcopenia foi realmente o grupo suplementado por proteínas parcialmente hidrolisadas. Paralelamente a esse estudo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The cheese whey hydrolysates have been widely used for various purposes. Depending on the enzymes used and the reaction medium, we can obtain hydrolysates with different characteristics. The purpose of this study was to hydrolyze bovine cheese whey proteins in different ways, varying the temperature of reaction and enzyme addition, in order to obtain hydrolysates with different degrees of hydrolysis for application in animal tests. The hydrolysates chosen for application in biological assays were obtained by the action of enzymes pepsin, trypsin, chymotrypsin and carboxypeptidase at 50°C. Two different hydrolysates were prepared: one with a larger amount of small peptides (oligo-, di-and tripeptides) and another with larger amount of free amino acids. Serum without hydrolysis was also used as a supplement to another group of animals. The intention was to test the two different hydrolysates and whey without hydrolysis as a supplement to old age rats in order to minimize the sarcopenia. Several studies indicate that formulas containing oligopeptides, especially di-and tripeptides, have higher nutritional value than an equivalent mixture of free amino acids or intact proteins. Taking this information as a basis, the research was then outlined expecting that the group supplemented with partially hydrolyzed protein could obtain a better performance in reducing the sarcopenia. The all 3 supplemented groups showed increase in muscle mass and bone and differ significantly from control (not supplemented). However, the group who presented the most positive effects in reducing the sarcopenia was actually the group supplemented with partially hydrolyzed protein. In parallel with this study, in sandwich PhD, the attainment of immobilized pepsin and trypsin (derivatives) in solid support, stable was studied, for further application to obtain... (Complete abstract click electronic access below) / Doutor
3

Produção e aplicação de hidrolisado de proteínas do soro de queijo bovino no preparado de suplemento nutricional: minimização da sarcopenia em ratos idosos

Marques, Daniela Parreira [UNESP] 18 December 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-18Bitstream added on 2014-06-13T19:19:56Z : No. of bitstreams: 1 marques_dp_dr_arafcf.pdf: 1011746 bytes, checksum: 390ce3f3fe90df8ee33232cb2c868a7d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação para o Desenvolvimento da UNESP (FUNDUNESP) / Os hidrolisados de proteínas do soro de queijo vêm sendo amplamente utilizados para diversos fins. Dependendo das enzimas utilizadas e meio de reação, podemos obter hidrolisados com diferentes características. O intuito do presente trabalho foi hidrolisar as proteínas do soro de queijo bovino de diferentes maneiras, variando-se a temperatura de reação e modo de adição das enzimas, a fim de se obter hidrolisados com diferentes graus de hidrólise para posterior aplicação em ensaios animais. Os hidrolisados escolhidos para aplicação nos ensaios biológicos foram obtidos pela ação das enzimas pepsina, tripsina, quimotripsina e carboxipeptidase a 50ºC. Dois hidrolisados diferentes foram preparados: um com maior quantidade de pequenos peptídeos (oligo, di e tripeptídeos) e outro com maior quantidade de aminoácidos livres. O soro sem hidrólise também foi utilizado como suplementação para um outro grupo de animais. A intenção foi testar os dois diferentes hidrolisados e o soro sem hidrólise como suplemento para ratos idosos, visando a minimização da sarcopenia. Diversos estudos apontam que fórmulas contendo oligopeptídeos, especialmente di- e tripeptídeos, possuem maior valor nutricional do que uma mistura equivalente de aminoácidos livres ou proteínas intactas. Tomando-se como base essa informação, delineou-se a pesquisa esperando-se que, o grupo suplementado com as proteínas parcialmente hidrolisadas obtivesse um melhor desempenho na minimização da sarcopenia. Todos os 3 grupos suplementados obtiveram aumento na massa muscular e óssea diferindo significativamente em relação ao controle (não suplementado) porem, o que apresentou efeitos mais positivos na minimização da sarcopenia foi realmente o grupo suplementado por proteínas parcialmente hidrolisadas. Paralelamente a esse estudo... / The cheese whey hydrolysates have been widely used for various purposes. Depending on the enzymes used and the reaction medium, we can obtain hydrolysates with different characteristics. The purpose of this study was to hydrolyze bovine cheese whey proteins in different ways, varying the temperature of reaction and enzyme addition, in order to obtain hydrolysates with different degrees of hydrolysis for application in animal tests. The hydrolysates chosen for application in biological assays were obtained by the action of enzymes pepsin, trypsin, chymotrypsin and carboxypeptidase at 50°C. Two different hydrolysates were prepared: one with a larger amount of small peptides (oligo-, di-and tripeptides) and another with larger amount of free amino acids. Serum without hydrolysis was also used as a supplement to another group of animals. The intention was to test the two different hydrolysates and whey without hydrolysis as a supplement to old age rats in order to minimize the sarcopenia. Several studies indicate that formulas containing oligopeptides, especially di-and tripeptides, have higher nutritional value than an equivalent mixture of free amino acids or intact proteins. Taking this information as a basis, the research was then outlined expecting that the group supplemented with partially hydrolyzed protein could obtain a better performance in reducing the sarcopenia. The all 3 supplemented groups showed increase in muscle mass and bone and differ significantly from control (not supplemented). However, the group who presented the most positive effects in reducing the sarcopenia was actually the group supplemented with partially hydrolyzed protein. In parallel with this study, in sandwich PhD, the attainment of immobilized pepsin and trypsin (derivatives) in solid support, stable was studied, for further application to obtain... (Complete abstract click electronic access below)
4

Heat Stability of Residual Milk Clotting Enzymes in Cheese Whey

Duersch, James Winter 01 May 1976 (has links)
Eliminating calcium chloride and replacing whole casein with k-casein eliminated clouding and sharpened diffusion boundaries in casein-agar gels used for the estimation of residual milk clotting enzymes in curd and whey. It also eliminated the need for a highly purified calcium-free agar. The substrate contained .54 percent k-casein, 3.6 percent sodium acetate, .73 percent bacto-agar and 95.13 percent water. The pH was adjusted to 5.9 with .lN hydrochloric acid. Proteases derived from Mucor pusillus var Lindt, Mucor Miehei and Endothia parasitica, as well as rennet, procine and bovine pepsins were used at recommended levels to set milk for Cheddar cheese manufacture. Whey samples from each lot were taken at draining and adjusted to pH 5.2, 5.6, 6.0, 6.2, 6.6 and 7.0 prior to being heated to 68.3C, 71.1C and 73.9C for .25, .5, 1, 5, and 10 minutes. Enzyme activities were assayed before and after heating. Mucor miehei protease was the most heat stable at all pH values followed by Mucor pusillus protease, rennet, bovine pepsin, E. parasitica protease and porcine pepsin. The heat stability of all enzymes except E. parasitica protease decreased with increasing pH, E. parasitica protease decreased with decreasing pH. All enzymes were inactivated at the minimum heat treatment at pH 7.0 except E. parasitica protease which was most stable at that pH. At pH 5.2 M. miehei protease persisted after a 10 minute treatment at 73.9C.
5

Improved Fermentation Process for Producing Methane from Cheese Whey

Awad, AbdulRaman Y. 01 May 1982 (has links)
Two methods of single-stage fermentation were used to produce methane from whey. The first method involved batch fermentation in which the pH was automatically controlled at 7.0. In addition to pH control, the second method was characterized by introducing the substrate continuously into the fermenter along with dilution water to keep the organic acids at a non-toxic level. The first method did not improve the production of methane compared to the batch fermentation in which a pH control system was not used (41). However, the second method showed that the concentration of organic acids has a major effect on limiting the production of methane from whey, and that by diluting the substrate with water the concentration of these acids was kept at levels not toxic to methanogenic bacteria until the population of methanogenic bacteria was such that they could convert organic acids to methane as rapidly as the acids were produced by non-methanogenic bacteria in a continuous process. This continuous process was capable of producing .179 m3 methane per kilogram of lactose in cheese whey.
6

Μελέτη επίδρασης pH και θερμοκρασίας στη ζύμωση τυρογάλακτος με Kluyveromyces marxianus

Καρατζάβελου, Ευαγγελία 04 December 2014 (has links)
Το τυρόγαλα είναι το βασικό απόβλητο των γαλακτοβιομηχανιών με σημαντικές περιβαλλοντικές επιπτώσεις, λόγω του υψηλού οργανικού του φορτίου, κυρίως της λακτόζης (4,8-5% w/v) που περιέχει. Στην παρούσα εργασία χρησιμοποιήθηκε ο ζυμομύκητας Kluyveromyces marxianus για τη ζύμωση του τυρογάλακτος προς παραγωγή αιθανόλης και προσδιορίσθηκαν οι βέλτιστες φυσικοχημικές συνθήκες (pH και θερμοκρασία) για τη διεργασία. Τα αποτελέσματα έδειξαν ότι σε pH 5,5 και 30oC επιτυγχάνεται μέγιστη ταχύτητα ζύμωσης και συγκέντρωση αιθανόλης. Στις ίδιες συνθήκες, μέτρηση του ρυθμού πρόσληψης λακτόζης επισημασμένης με 14C από το μικροοργανισμό έδειξε ότι αυτός σχετίζεται άμεσα με την κινητική της ζύμωσης. / Cheese whey is the main waste of dairy industries with significant environmental impacts due to the high organic load, mainly lactose (4,8-5% w / v) containing. In this work we used the yeast Kluyveromyces marxianus for whey fermentation to produce ethanol and determined the optimal physico-chemical conditions (pH and temperature) for the process. The results showed that at pH 5,5 and 30oC achieve maximum speed of fermentation and ethanol concentration. Under the same conditions, measuring the rate of uptake of 14C-labeled lactose by the microorganism showed that this is directly related to the kinetics of fermentation.
7

Développement d'un procédé de production d'hydrogène photofermentaire à partir de lactosérum / Conception production and application of a photosynthetic process for the hydrogen production from whey.

Castillo Moreno, Patricia 17 May 2018 (has links)
L'hydrogène est une source d'énergie précieuse en tant que source d'énergie propre et que matière première pour des innombrables industries.Les procédés biologiques de production d'hydrogène gagnent en importance en raison de leurs avantages opérationnelles et de leur polyvalence dans les substrats utilisés (y compris les eaux usées).Dans cette thèse doctoral, on a développé une méthodologie photo-fermentative de production d'hydrogène en utilisant du lactosérum en tant que substrat pour la bactérie Rhodobacter capsulatus IR3::LacZ et B10::LacZ.Ce projet a été réalisé en trois étapes, exposées dans les différents chapitres.Dans la première étape on a identifié les facteurs pertinents pour la production de l'hydrogène avec du sérum synthétique en utilisant la méthodologie de plan d'expériences.Les résultats de cet étape on a obtenu quatre modèles statistiques et on a choisi la souche IR3::LacZ pour les expériences avec du lactosérum industriel.Le rendement volumétrique maximal et le rendement produit / substrat Y P/S obtenus pour la première étape ont été de 64 ml h-1L-1 et 2,08 mol H2 mol-1 C (“C” représente la source de carbone dans ce cas lactose et lactate) pour la solution amortissant le phosphate et 43.01 ml h-1L-1 y 2.52 mol H2 mol-1 C pour la solution Kolthoff.Dans la deuxième étape, on a évalué la production d'hydrogène avec du lactosérum industriel. On a appliqué un pré-traitement de trois étapes avant d'utiliser le lactosérum comme substrat : réduction du contenu gras, déprotéinisation et stérilisation. On a obtenu un modèle validé qui décrit la production d'hydrogène seulement pour la solution amortissant de phosphate. Le rendement volumétrique maximal et le YP/S ont été de 45.93 ml h-1L-1 et de 2.29 mol H2 mol-1 C respectivement. On a déterminé que l'addition d'une étape d’homo-fermentation au processus de prétraitement es avantageuse au rendement du processus. On a obtenu une productivité volumétrique de 69.71 ml h-1L-1 et de YP/S de 2.96 mol H2 mol-1 CLa troisième étape a été la mise à l'échelle des expériences à réacteurs de 1,5 L pour sérum synthétique et de 1L pour serum industriel. On a décelé de la contamination dû à la présence d'un processus de fermentation, lequel a généré une haute production de biogas composé exclusivement par H2 y CO2 ce dernier dans une concentration non superieur à 30% (v/v).Pour ces raisons, on a conclu que conclu que le processus de production intégré, en couplant la fermentation obscure et la photo-fermentation est une option avec un énorme potentiel pour l'utilisation de lactosérum comme substrat dans la production d'hydrogène. / Hydrogen is a valuable gas use as a clean energy source and feedstock for some industries. Biological hydrogen production processes are gaining importance due to their operational conditions and versatility in the substrates (including wastewater). A hydrogen production photo fermentative methodology was developed using cheese whey as a substrate for the bacteria Rhodobacter capsulatus strain IR3::LacZ and B10::LacZ . The project was carried out in three stages.The purpose of the first stage is to identify the relevant factors to produce hydrogen for a synthetic whey medium in a photofermentation process, using the Design of Experiments methodology. The products of this stage are four statistical models, obtained for each strain and buffer solution studied. The strain IR3::LacZ was selected for the experiments with industrial whey as substrate. The maximum volumetric yield and the product/substrate yield YP/S were 64 ml h-1L-1 and 2.08 mol H2 mol-1 C (C is the carbon source in this case lactose and lactate) and 43.01 ml h-1L-1 and 2.52 mol H2 mol-1 C for phosphate buffer and Kolthoff buffer, respectively.In the second stage the production of hydrogen with industrial whey was evaluated. A three-step pre-treatment was applied before using industrial cheese whey as substrate: fat reduction, deproteinization and sterilization. A validate statistical model describing hydrogen production was only obtained for phosphate buffer. The maximum volumetric yield and the product/substrate yield YP/S were 45.93 ml h-1L-1 and 2.29 mol H2 mol-1 C respectively. The addition of an homofermentation to the pretreatment improved the production yield, in this case a volumetric productivity of 69.71 ml h-1L-1 and a YP/S of 2.96 mol H2 mol-1 C were obtained.The third stage was the scale-up to 1.5 and 1 reactor L for synthetic whey and 1L for synthetic and industrial whey respectively. A fermentative process appeared due to a bacterial contamination, leading to a high biogas production. Biogas was exclusively composed of H2 and CO2 the last in a concentration not exceeding 30% (v/v). For this reason, it was concluded that the integrated production process coupling dark and photo fermentations) is an option with great potential for the use of whey as substrate in the production of hydrogen.
8

Aproveitamento de soro desproteinado de queijo para produção de goma xantana por X. campestris ATCC 13951 / Use of de-proteinated cheese whey to production of xanthan gum by X. campestris ATCC 13951

Sobenes Gutiérrez, Jenny Roxana, 1979- 23 August 2018 (has links)
Orientador: Ranulfo Monte Alegre / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-23T10:10:46Z (GMT). No. of bitstreams: 1 SobenesGutierrez_JennyRoxana_M.pdf: 1378752 bytes, checksum: 422ae3abb0f6df0de59c85a305ea8495 (MD5) Previous issue date: 2013 / Resumo: O presente trabalho teve como objetivo estudar a produção de goma xantana utilizando x. campestris ATCC 13951 e soro de queijo desproteinado. Foram feitos ensaios preliminares para determinar as condições de fermentação: 29 °C, pH inicial 7,0 e 180 rpm em agitador orbital por 72 horas. Fez-se dois planejamentos experimentais utilizando as variáveis: concentração de lactose no soro de queijo, concentração de extrato de levedura e sulfato de amônio ou uréia como fonte de nitrogênio. O melhor resultado quanto à produção de goma foi obtido com meio contendo soro desproteinado, lactose (44 g/L), extrato de levedura (3 g/L) e sulfato de amônio (1,5 g/L) cuja produção de goma alcançou 20,28 g/L em 72 h de fermentação. Em meio constituído de soro desproteinado, lactose (44 g/L), extrato de levedura (3 g/L) e uréia (2 g/L) no lugar de sulfato de amônio, a produção de goma alcançou 18,96 g/L. Entretanto, utilizando apenas o soro de queijo desproteinado, a produção de goma foi praticamente a mesma, atingindo 19,68 g/L. Portanto, a suplementação do soro de queijo desproteinado com fontes de nitrogênio para produção de goma xantana é desnecessária, visto que as frações de proteínas e outros compostos nitrogenados do leite foram suficientes para suprir este elemento à bactéria. O aumento da concentração de lactose no soro desproteinado não aumentou a produção de goma, obtendo-se melhores resultados em meio com baixa concentração da fonte de carbono. Sendo o soro de queijo um sub-produto abundante e de baixo custo, este processo torna-se interesante na produção de goma xantana, visto que este polissacarídeo tem importante utilização a nivel industrial sendo atualmente muito utilizada na elaboração de produtos alimenticios / Abstract: The objective of this work was to study the xanthan gum production using x. campetris ATCC 13951 and de-proteinated cheese whey. Some preliminary assays indicated as good fermentation condition 29 °C, initial pH 7.0 and 180 rpm in shaker during 72 hours. Some assays were done obeying experimental planning being the variables the lactose concentration at the de-proteinated cheese whey, yeast extract concentration and ammonium sulfate or urea as nitrogen source. The best result was obtained in the medium using de-proteinated cheese whey containing 44 g/L of lactose, 3 g/L of yeast extract and 1.5 g/L of ammonium sulfate, where the gum production reached 20.28 g/L. At the medium using de-proteinated cheese whey (44 g/L of lactose), yeast extract (3 g/L) and ammonium sulfate replaced by urea (2 g/L) the gum reached 18.96 g/L. However, when the de-proteinated cheese whey was used alone as culture medium the gum production, almost reached the same concentration (19.68 g/L). Therefore, the cheese whey supplementation with nitrogen sources to xanthan gum production is not necessary, since the protein fractions and others compounds containing nitrogen from whey that remain in the de-proteinated cheese whey are sufficient to supply this element at the bacteria. The increase of the lactose concentration in the de-proteinated cheese whey do not increase the gum production obtaining better results in half with low concentration of carbon source. Cheese whey is an abundant and low cost byproduct, so this process becomes interesting for the production of xanthan gum, since it has important industrial use bing widely used in the preparation of food products / Mestrado / Engenharia de Alimentos / Mestra em Engenharia de Alimentos
9

Biotechnologická produkce vybraných metabolitů na syrovátkovém substrátu / Biotechnological production of selected metabolites on whey substrate

Gadová, Martina January 2017 (has links)
The submitted master thesis deals with assessment of the possibility of using of cheese whey for biotechnological production. Study content composition of lyophilized whey, optimization of acid hydrolysis and preparation of cultivating mediums with different content and treatment of cheese whey. Between the aims of this thesis belong also screening of microbial producers, interesting for biotechnology and looks at their growth and production of selected metabolites of cultivation mediums containing cheese whey. All substrates and produced metabolites where examined with UHPLC-PDA-RI and GC-FID: Amount of produced microbial lipids was determined by gravimetric analysis. Examined microorganisms belonged to yeast genus Saccharomyces, Metschnikowia and bacterial genus Lactobacillus and its focused on production of ethanol, microbial lipids and lactic acid. The highest yields with using yeasts were obtained using production medium containing hydrolysed lactose in cheese whey. The highest production, in case of bacteria, was obtained using non-hydrolysed, untreated cheese whey production medium.
10

OptImisation of the H-type microbial fuel cell using whey as a substrate

Kassonga, Josue 13 September 2011 (has links)
MSc, Faculty of Science, University of the Witwatersrand, 2011 / A growing interest is on the biological remediation of pollutants with the added benefit of generating electricity in microbial fuel cells (MFCs). Therefore, the analyses of suitability and potential of full-strength paper mill effluent and cheese whey were separately investigated in such devices. The most promising effluent was selected for biofilm optimization studies. In the biofilm buildup studies, anodes were enriched with microorganisms inherent to whey for a period between one and three months before their application in reactors. Independently, pre-incubated electrodes which were two-month-old were used serially in four MFCs of seven days each. In the preliminary study, the maximum power densities were 24 ± 3 mW/m2 (0.02 % coulombic efficiency − εcb) and 16.7 ± 1.8 W/m2 (εcb = 3.7 %) in paper mill effluent and whey, respectively. Following a three-month acclimation of whey anodophilic microbes, the power increased to 1 800 W/m2 (εcb = 80.9 %) and 92.8 % total chemical oxygen demand (tCOD) removal after a single batch cycle in MFCs. In anode recycling experiments, the operation was characterised by power of 390 ± 21 W/m2 (εcb = 0.25 %) in the third anode reuse; whilst the second reactor cycle had the highest tCOD removal (44.6 %). The anodophilic microbial species identified in cheese whey were from the Lactobacillus genus. This study concluded that wastes can supply fuel for power generation with simultaneous remediation; whey had greater potential than paper mill effluent; and both continual acclimation of inherent waste microbes and anode recycling improved the performance of MFCs.

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