Casein is the major protein fraction in milk, and its cross-linking has been a topic of scientific interest for many years. Enzymatic cross-linking has huge potential to modify relevant techno-functional properties of casein, whereas non-enzymatic cross-linking occurs naturally during the storage and processing of milk and dairy products. Two size separation techniques were applied for characterisation of these reactions: gel electrophoresis and size exclusion chromatography. This review summarises their separation principles and discusses the outcome of studies on cross-linked casein from the last ~20 years. Both methods, however, show limitations concerning separation range and are applied mainly under denaturing and reducing conditions. In contrast, field flow fractionation has a broad separation range and can be easily applied under native conditions. Although this method has become a powerful tool in polymer and nanoparticle analysis and was used in few studies on casein micelles, it has not yet been applied to investigate cross-linked casein. Finally, the principles and requirements for absolute molar mass determination are reviewed, which will be of increased interest in the future since suitable calibration substances for casein polymers are scarce.

Im Rahmen dieser Arbeit ist es durch die kombinierte Anwendung von P-31 Flüssigkeits (HR)- NMR-Spektroskopie sowie dynamischer Lichtstreuung (DLS) gelungen, die supramolekulare Struktur von mizellarem Casein aus ultrahocherhitzter (UHT) Milch unter dem Einfluss einer enzymatischen Vernetzung mittels mikrobieller Transglutaminase (mTG) zu charakterisieren. Die P-31 HR NMR-Spektroskopie erweist sich dabei als hervorragende Methode, um sowohl den Einbau von Casein aus dem Milchserum in die mizellaren Aggregate durch die enzymatische Reaktion als auch die bevorzugte mTG Vernetzung des beta-Caseins nachzuweisen. Durch die Kombination von P-31 HR NMR-Spektroskopie und Messungen der dynamischen Lichtstreuung war es weiterhin möglich, das Vorliegen vernetzter Caseinaggregate in Dispersionen mTG-behandelter Caseine zu belegen und besonders den Anteil an nicht vernetztem Casein „sichtbar“ zu machen, der durch EDTA-Zugabe aus den mTG-vernetzten Caseinnetzwerken freigesetzt wird. Es zeigt sich, dass die Caseinnetzwerke nach der EDTA-Behandlung eine geringere Proteindichte als mizellares Casein aufweisen, da sie nur ca. 20 % des Serinphosphats des mizellaren Caseins enthalten. P-31 Festkörper-NMR-spektroskopische Messungen legen außerdem nahe, dass die Beweglichkeit des phosphorylierten Ser149-Restes des kappa-Caseins in der äußeren Schicht der mizellaren Caseinaggregate durch die mTG-Behandlung nicht wesentlich verändert wird. Um die erhaltenen Caseinnetzwerke im Hinblick auf ihr Anwendungspotential zu untersuchen, wurden sie als Proteinkomponente bei der biomimetischen Calciumphosphatfällung sowie als Trägerstrukturen für bioaktives Lysozym verwendet. Durch den Einsatz von Caseinnetzwerken als Fällungsmedium während der Präzipitation von Calciumphosphat (CaP) ist es gelungen, eine hydratisierte, apatitische Phase zu stabilisieren, die sowohl ungeordnete als auch kristalline Bereiche enthält und damit strukturelle Ähnlichkeit zu biologisch und besonders biomimetisch gebildetem Apatit besitzt. Die in den Präzipitaten ebenfalls vorhandenen Phosphoratome in einer relativ ungeordneten OCP (Octacalciumphosphat)-ähnlichen Umgebung stehen höchstwahrscheinlich mit der apatitischen Phase in räumlich engem Kontakt und sind damit entweder Bestandteil dieser Phase oder befinden sich in einer getrennten Phase, die jedoch mit der apatitischen Phase in Form eines Nanokomposits mit sehr kleinen, eng benachbarten Kristalliten vorliegt. Bei der Fällung des Caseinnetzwerk/CaP-Präzipitats wird ebenfalls eine Dicalciumphosphat-Dihydrat (DCPD)-Phase gebildet. Diese ist separiert von den anderen CaP-Phasen und tritt in wesentlich geringerem Maße auf als in einem reinen CaP-Präzipitat, das ohne Proteinkomponente gefällt wurde. Damit konnte gezeigt werden, dass unter Bedingungen, bei denen ohne Proteinkomponente größtenteils DCPD entsteht, die Caseinnetzwerke eine apatitische Phase stabilisieren, die strukturelle Ähnlichkeit zu biologisch und biomimetisch gebildetem Apatit aufweist. Die qualitativ gleichen Ergebnisse konnten für vergleichsweise untersuchtes unvernetztes Casein gefunden werden. Die Caseinnetzwerke zeigen jedoch in Bezug auf die apatitische Phase einen stärkeren Stabilisierungseffekt als unvernetztes Casein. Es ist denkbar, dass dies unter anderem darauf zurückzuführen ist, dass die Phosphatzentren in den Caseinnetzwerken im Gegensatz zu Casein frei von CaP-Brücken sind, da diese durch die EDTA-Behandlung entfernt wurden. Da die Caseinnetzwerke zudem eine geringere Proteindichte und damit eine höhere „Porosität“ als die mizellaren Caseinaggregate aufweisen, kann sich die apatitische Phase möglicherweise auch innerhalb der Netzwerke bilden, während dies für die mizellaren Caseinaggregate wahrscheinlich nur begrenzt möglich ist. In der vorliegenden Arbeit konnte ebenfalls gezeigt werden, dass sich Caseinnetzwerke grundsätzlich als Transportsysteme für Lysozym eignen, da sie eine hohe Stabilität aufweisen und erfolgreich mit Lysozym beladen werden können. Während die Assoziation von Lysozym mit mizellaren Caseinaggregaten, die aus UHT-Milch gewonnenen wurden, zu einem fast vollständigen Verlust der Lysozymaktivität führt, bleibt die Aktivität des Enzyms bei der Bindung an Caseinnetzwerke erhalten. Das Anwendungspotential der Caseinnetzwerk/Lysozym-Assoziate wurde im Rahmen von zahnmedizinischen Versuchen in vitro und in situ untersucht. Es konnte nachgewiesen werden, dass die Caseinnetzwerk/Lysozym-Assoziate in vitro eine dauerhafte Immobilisierung des Lysozyms in der in situ gebildeten Pellikel bewirken. Eine deutliche Anreicherung des Enzyms in situ wird mithilfe der Caseinnetzwerke allerdings nicht beobachtet. Dies könnte darin begründet sein, dass die im Vergleich zu den in vitro vorgefundenen Verhältnissen deutlich komplexeren Bedingungen in situ zu einem selektiveren Anreicherungsprozess von Enzymen in der Pellikel führen.

Polzerová, I: Use of kinase modulation in the Alzheimer's disease pathogenesis. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2016, 91 p. Data used in this Diploma Thesis have been taken from foreigner scientific literary sources. It provides the summary of the not yet explored natural compounds from marine organisms with kinase inhibitory activity. The first chapter Alzheimer's disease describes a characteristic of the disease, its etiopathogenesis, risk factors and currently available treatment. At the beginning of the second chapter are mentioned new perspective approaches to treatment of Alzheimer's disease. Most of this chapter deals with kinases as potential therapeutic targets in the treatment of Alzheimer's disease. In the chapter, physiologic and pathophysiologic functions of GSK-3β and CK-1δ are described in the organism, and also, other kinases are mentioned which are involved in the pathogenesis of the disease. Next part dedicates analytical methods suitable for testing activity and inhibition of kinases in vitro and in silico, also deals with summary of the synthetic kinase inhibitors and characterizes an their properties. In this chapter is also described main part of this work - the...

La caséine [bêta] (CN-[bêta]) et la caséine [alpha]s1 (CN-[alpha]s1) du lait de jument possèdent un taux variable de phosphorylation et sont de bons modèles d’étude de l’influence du degré de phosphorylation et de la séquence peptidique sur la chélation de caséinophosphopeptides (CPP) avec des minéraux d’intérêt nutritionnel. Avant d’envisager une telle étude, la structure des caséines doit être déterminée précisément. Notre travail a été consacré à la caractérisation de variants post-transcriptionnels et post-traductionnels de CN-[alpha]s1 et de CN-[bêta]. Après fractionnement chromatographique et analyse par spectrométrie de masse, la CN-[alpha]s1 entière, trois variants d’épissage alternatif des exons 7 et 14 de la CN-[alpha]s1 et quatre variants délétés du résidu Gln91, résultat de l’utilisation d’un site d’épissage cryptique, ont été identifiés dans le lait équin. Nous avons montré que le degré de phosphorylation de ces isoformes varie de 2 à 8 groupes phosphates. Au total, 36 isoformes différentes de CN-[alpha]s1 ont été caractérisées. La cartographie bidimensionnelle de la CN-[bêta] a été établie avec précision après avoir isolé par chromatographie chacun des variants de phosphorylation (possédant de 3 à 7 groupes phosphates) et après avoir caractérisé les formes de CN-[bêta] modifiées par désamidation non enzymatique du résidu Asn135. Des CPP trypsiques de chaque variant de phosphorylation ont été préparés avec une technique récente de chromatographie d’affinité au dioxyde de titane, ce qui a permis de localiser par spectrométrie de masse en tandem les sites phosphorylés de la CN-[bêta] (Ser9, Ser10, Thr12, Ser18, Ser23, Ser24, Ser25) et de montrer que la phosphorylation de la CN-[bêta] n’est pas aléatoire mais séquentielle / Equine [bêta]-casein ([bêta]-CN) and [alpha]s1-casein ([alpha]s1-CN) have a variable phosphorylation degree and are good models for the study of the influence of phosphorylation degree and peptide sequence on chelation of caseinophosphopeptides (CPP) with minerals of nutritional interest. Before considering such study, structure of caseins must be precisely determined. Our work has been devoted to the characterization of post-transcriptional and post-translational variants of [alpha]s1-CN and [bêta]-CN. Concerning [alpha]s1-CN, the full-length protein, three alternative splicing variants involving exons 7 and 14 and four variants involving cryptic splice site resulting in deletion of residue Gln91 have been identified in mare’s milk after chromatographic fractionation and mass spectrometric analysis. The phosphorylation degree of these variants varies between 2 and 8 phosphate groups. Finally, 36 isoforms of [alpha]s1-CN have been identified. Isolation of each phosphorylation variant (having 3 to 7 phosphate groups) of [bêta]-CN by chromatography, and characterization of modified forms of [bêta]-CN by non enzymatic deamidation of residue Asn135 permits the establishment of bidimensional cartography of [bêta]-CN with precision. After hydrolysis by trypsin, CPP of each phosphorylation variant have been prepared by affinity chromatography to titanium dioxide, a recent technology, which allowed to locate by mass tandem spectrometry the phosphorylated sites of [bêta]-CN (Ser9, Ser10, Thr12, Ser18, Ser23, Ser24, Ser25). It was shown that the phosphorylation of [bêta]-CN is not a random process but follows a sequential way

The task of this diploma thesis was to investigate the influence of inorganic pigments on the identification of casein oil and animal glue tempera by mass spectrometry MALDI- -TOF MS (Matrix-Assisted Laser Desorption/Ionisation - Time of Flight Mass Spectrometry). First, it was necessary to prepare a set of model colour layers containing casein and animal glue tempera together with ten inorganic pigments. Consequently, the method of peptide mass fingerprinting was used to obtain mass spectra of the samples. Finally, it was possible to compare and determine the characteristic peptide fragments for both proteinaceous binders and find pigments that most affected the identification of casein and rabbit glue temperas. The obtained values of m/z casein oil tempera and animal glue tempera were used to improve and complete reference database of protein binders that is used to identify protein binders in works of art at the Institute of Chemical Technology in Prague.

Os peptídeos INKKI e YPVQPFTE foram isolados a partir da hidrólise da b-caseína bovina e correspondem às seqüências 26-30 e 114-121 respectivamente. A atividade proliferativa foi avaliada em culturas primárias de linfócitos T. A atividade antitumoral in vitro foi realizada em culturas de B16F10. Foi utilizado grupo com 40 camundongos da linhagem C57BL/6J para avaliar a atividade antitumoral. Nossos resultados mostraram que o peptídeo INKKI apresentou resposta proliferativa semelhante ao mitógeno comercial PHA. O peptídeo YPVEPFTE mostrou ter ação proliferativa maior do que a apresentada pelo mitógeno comercial PHA. O peptídeo INKKI mostrou ação quimiotáxica. O tratamento in vitro mostrou que somente o pentapeptídeo INKKI induz seletiva atividade citotóxica para as células de melanoma. Os animais portadores de tumores dorsais apresentaram significativa inibição da capacidade de crescimento e a metastatização. Conclui-se que os peptídeos apresentam ação significativa tanto nos experimentos in vitro como in vivo sugerindo um possível papel fisiológico. / Peptides INKKI and YPVQPFTE were isolated from the bovine b-casein after hydrolysis corresponding to the 23-30 and 114-121 sequence, respectively. Evaluation of the proliferative activity in primary cultures of lymphocytes. The activity antitumor in vitro was accomplished culture of was studied. Groups with 40 C57BL/6J lines mice had been used to evaluate the antitumoral activity. Our results showed that peptide presented similar proliferative response to the PHA commercial mitogen. The peptide YPVEPFTE showed to have proliferative action larger than presented by the commercial mitogen. The peptide INKKI showed in the chemotactic action. The treatment in vitro had shows that the peptide INKKI induces selective citotoxicity. The bearing animals of dorsal tumors had presented significant inhibition of the capacity of growth and the spread of methastasis. Thus, the peptides casein present significant action in in vitro and in vivo experiments, suggesting a possible physiologic role.

A caseína e os ácidos graxos livres (AGL) são importantes componentes do leite relacionados às suas características industriais e sensoriais. Alguns fatores são responsáveis por alterações em suas concentrações, dentre eles, pode-se destacar as condições de armazenamento, além da agitação e, principalmente, a contagem de células somáticas (CCS). Para estudar tais alterações, avaliou-se através do presente estudo o efeito da temperatura de armazenamento (- 20oC e 7oC) e da idade das amostras (3, 6, 9 e 12 dias), assim como da CCS (CCS1: 400 mil, CCS2:400-750 mil e CCS3: 750 mil células somáticas/mL de leite). O efeito das condições de armazenamento sobre a caseína e os AGL foi avaliado no primeiro estudo. O efeito da CCS sobre a caseína e os AGL, por outro lado, foi avaliado no segundo estudo. No primeiro estudo, observou-se aumento nos teores de AGL ao longo do tempo, ou seja, acompanhando o aumento do período de armazenamento, com médias superiores em amostras resfriadas (7oC), em relação às congeladas (-20oC). Desta forma, sugere-se que análises laboratoriais devem ser realizadas em até três dias para este componente, devido ao seu aumento progressivo em amostras resfriadas. Para a caseína, entretanto, não foi identificada interação entre os fatores idade e temperatura. As médias deste componente não diferiram considerando-se as condições de armazenamento avaliadas, indicando que as análises para este componente podem ser realizadas até doze dias após a coleta, independente da temperatura de armazenamento. No segundo estudo, identificou-se interação entre classes de CCS e época de coleta, para caseína. A partir dos resultados de AGL, pode-se concluir que o leite encontra-se com altas concentrações deste componente, quando coletado na propriedade rural, sendo também observada influência da CCS sobre as concentrações de caseína e AGL no leite cru. Os AGL apresentaram incrementos significativos comparando-se amostras coletadas em diferentes locais, no trajeto da fazenda à indústria. Por outro lado, comparando-se os mesmos locais: tanque, rota e silo, as médias de caseína não diferiram. Observou-se correlação entre as variáveis CCS e caseína e CCS e AGL. / The casein and the free fatty acids (FFA) are important milk components related to its industrial and sensory characteristics. Some factors are responsible for changes in their concentration among them can highlight the storage conditions, as well as agitation and, especially, the somatic cell count (SCC). To study such changes, we assessed through the present study the effect of storage temperature (-20oC and 7oC) and the age of samples (3, 6, 9 e 12 days), as well as the CCS (CCS1: 400 mil; CCS2: 400-750 mil; CCS3: 750 mil somatic cells/mL of milk). The effect of CCS storage conditions on casein and FFA was evaluated in the first study. The effect of CCS on casein and FFA moreover, was evaluated in the second study. In the first study, it was observed increased levels the AGL over time, ie, accompanying the increase of the storage period, with means higher in refrigerated samples (7oC), in relation to frozen samples (- 20oC). Thus, it is suggested that laboratory examinations shall be performed up to three days to this component, due to their progressive increase in refrigerated samples. For casein, however, was not identified interaction between the factors age and temperature. The mean of this component did not differ considering the storage conditions, indicating that the analyzes for this component can be made until twelve days after collection, regardless of storage temperature. In the second study, we identified interactions between CCS classes and seasons, for casein. From the FFA results, we can conclude that milk meets with high concentrations of this component, when collected in the rural property, being also observed influence of CCS on concentrations of casein and FFA in raw milk. The FFA showed significant increases compared to samples collected at different locations on the path from farm to industry. On the other hand, comparing the same locations, tank, route and silo, the casein average did not differ. Correlation was observed between the variables casein and CCS and FFA and CCS.

Este estudo teve como objetivo avaliar o efeito de níveis crescentes de uréia na dieta de vacas em lactação sobre a produtividade, características físico-químicas e de composição do leite, bem como composição da proteína do leite. Foram utilizadas nove vacas Holandesas em lactação, em delineamento experimental tipo quadrado latino 3X3, com 3 tratamentos, 3 períodos e 3 quadrados. O experimento teve duração total de 63 dias divididos em 3 períodos de 21 dias. Os tratamentos foram: tratamento A (controle) com dieta formulada para suprir 100% das exigências do NRC (2001) em termos de PB, proteína degradável no rúmen (PDR), proteína não degradável no rúmen (PNDR), utilizando farelo de soja como principal fonte protéica e cana-de-açúcar como volumoso; tratamento B, dieta com a inclusão de 0,75% de uréia, em substituição parcial ao farelo de soja, e tratamento C, dieta com inclusão de 1,5% de uréia, em substituição parcial ao farelo de soja. Todas as dietas foram isoenergéticas (1,53 Mcal/kg de energia líquida de lactação) e isoprotéicas (16% de proteína bruta). Não foram observadas diferenças entre os tratamentos, quando os resultados foram analisados por regressão polinomial simples, quanto a: consumo de matéria seca, produção de leite, produção de leite corrigida para 3,5%, produção de proteína, produção de gordura, produção de lactose e produção de sólidos totais e Log CCS. Também não houve influência dos tratamentos sobre pH, crioscopia, densidade e prova de resistência ao álcool. No entanto, a acidez, sofreu efeito linear decrescente (p = 0,017) em função dos níveis de uréia na dieta. Quanto à composição do leite, os teores de proteína, gordura, lactose, uréia, extrato seco total e extrato seco desengordurado não foram influenciados pelos tratamentos. A composição da proteína também não foi alterada pela inclusão de até 1,5% de uréia na dieta, não sendo observada diferença entre os tratamentos para a proteína bruta, proteína verdadeira, caseína, proteína do soro, nitrogênio não caseinoso, nitrogênio não protéico, uréia, bem como as relações proteína verdadeira: proteína bruta e caseína: proteína verdadeira. Estes resultados sugerem que o uso de até 1,5% de uréia na matéria seca da dieta não altera a capacidade de produção, as características físico-químicas e de composição do leite, bem como a composição da proteína do leite. / The aim of this study was to evaluate the effects of three different dietary levels of urea on milk yield and composition, and milk protein composition. Nine lactating Holstein cows were used in a 3X3 latin square arrangement, with 3 treatments, 3 periods of 21 days each and 3 squares. The treatments were: A) NRC-based (NRC, 2001) diet to provide 100% of crude protein (CP), as well as, rumen undegradable protein (RUP) and rumen degradable protein (RDP) requirements, by using soybean meal and sugar cane; B) 0,75% urea inclusion; partially substituting soya meal from diet C) 1,5% urea inclusion, partially substituting soya meal from diet. Energy and protein levels of treatment diets comply with NRC (2001), and were isoenergetic and isoproteic. No statistical differences were observed among treatments, when results were analyzed by simple polynomial regression in relation to dry-matter intake, milk yield, 3,5% FCM, protein and fat yield, and somatic cell count (Log SCC). Cryoscopy, pH, milk density and alcohol stability, fat, lactose, urea, total solids and solids with no fat were not influenced by treatments. The protein composition, crude protein, true protein, casein, whey protein, non-casein nitrogen, milk urea nitrogen, as well as, true protein:crude protein and casein:true protein ratios were not influenced by the substitution of soybean meal by urea in ration. Results indicate that the use of urea up to 1,5% in DM does not alter milk yield and its composition.

Made available in DSpace on 2014-07-29T15:23:44Z (GMT). No. of bitstreams: 1 Claudia Cantelli Daud Bordin.pdf: 1236989 bytes, checksum: 94e232b387133e7ac6ecf58487cc965e (MD5) Previous issue date: 2012-02-03 / Gelatin is widely used in human feed, but has limited protein value. The composition in essential amino acids is quite atypical, since the levels of all the amino acids are below the benchmark of Food and Nutrition Board of the Institute of Medicine of the National Academy of Sciences of USA (FNB/IOM), with the aggravating not contain tryptophan in its composition. This study evaluated the effectiveness of food and the quality of protein mixtures of casein with gelatin (4:1 protein-based), in diets with low protein levels. An experimental study on animal model using 36 wealing male Wistar rats (21 to 23 days of age), divided into six groups of six animals each. The following were fed with diets: C10: 10% protein (casein); C8G2: 10% protein (8% casein; 2% gelatin); C12.5: 12.5% protein (casein); C10G2.5: 12.5% protein (10% casein; 2.5% gelatin); G10: 10% protein (gelatin); AP: protein-free. The duration of the experiment was 28 days for groups C10; C8G2; C12.5 e C10G2.5 and 14 days for groups G10 e AP. The effectiveness of food diets containing mixing casein:gelatin was influenced by the gelatin, according to the Food Conversion Ratio to protein level of 10% (C10 = 3.35 ± 0.19 versus C8G2 = 3.91 ± 0.34) and in supplementation with gelatin (C10 = 3.35 ± 0.19 versus C10G2.5 = 3.86 ± 0.32). The protein effectiveness was reduced in the protein level of 10% (C10 = 2.90 ± 0.17 versus C8G2 = 2.41 ± 0.22), in protein level of 12.5% (C12.5 = 2.32 ± 0.19 versus C10G2.5 = 2.03 ± 0.16) and supplementation with gelatin (C10 = 2.90 ± 0.17 versus C10G2.5 = 2.03 ± 0.16) according PER (Protein Efficiency Ratio). The animals that consumed gelatin (G10) had similar weight loss to the protein-free group. Gelatin in mixtures of casein with gelatin (4:1 protein-based), in diets with low protein content, reduces the effectiveness of food protein of casein. / A gelatina é amplamente utilizada na alimentação humana, porém tem valor proteico limitado. Sua composição em aminoácidos essenciais é bastante atípica, uma vez que os teores de todos esses aminoácidos são inferiores ao padrão de referência do Comitê de Nutrição e Alimentos do Instituto de Medicina da Academia Nacional de Ciências dos EUA (Food and Nutrition Board FNB, Institute of Medicine IOM), com o agravante de não conter triptofano em sua composição. Este estudo avaliou a eficácia alimentar e a qualidade proteica de misturas de caseína com gelatina (4:1 em base proteica), em dietas com baixos teores de proteína. Foi realizado um estudo experimental em modelo animal com 36 ratos albinos da linhagem Wistar, machos, recém-desmamados (21 a 23 dias de idade), divididos em seis grupos de seis animais cada. Foram alimentados com as seguintes dietas: C10: 10% proteína (caseína); C8G2: 10% proteína (8% caseína; 2% gelatina); C12,5: 12,5% proteína (caseína); C10G2,5: 12,5% proteína (10% caseína; 2,5% gelatina); G10: 10% proteína (gelatina); AP: aproteico. A duração do experimento foi de 28 dias para os grupos C10, C8G2, C12,5 e C10G2,5 e de 14 dias para os grupos G10 e AP. A eficácia alimentar das dietas contendo a mistura caseína:gelatina foi influenciada pela gelatina, segundo o Fator de Conversão Alimentar, ao nível proteico de 10% (C10 = 3,35 ± 0,19 versus C8G2 = 3,91 ± 0,34) e na suplementação com gelatina (C10 = 3,35 ± 0,19 versus C10G2,5 = 3,86 ± 0,32). A eficácia proteica foi reduzida tanto ao nível proteico de 10% (C10 = 2,90 ± 0,17 versus C8G2 = 2,41 ± 0,22) quanto ao nível proteico de 12,5% (C12,5 = 2,32 ± 0,19 versus C10G2,5 = 2,03 ± 0,16) e na suplementação com gelatina (C10 = 2,90 ± 0,17 versus C10G2,5 = 2,03 ± 0,16) segundo o PER (Protein Efficiency Ratio). Os animais que consumiram gelatina (G10) apresentaram perda de peso corpóreo, semelhante aos do grupo aproteico. A gelatina em misturas de caseína com gelatina (4:1 em base proteica), em dietas com baixo teor de proteína, reduz a eficácia alimentar e proteica da caseína.

Baigiamasis darbas atliktas Lietuvos Žemės ūkio universitete 2006 - 2008 metais. Magistro baigiamąjį darbą sudaro įvadas, 3 skyriai, išvados, literatūros sąrašas ir priedai. Darbo apimtis 48 puslapių, juose 25 paveikslai, 8 lentelės, naudotasi 46 literatūros šaltiniais. Tiriamojo darbo tikslas - padidinti plataus vartojimo, kasdienio produkto – rauginto pieno biologinę vertę, panaudojant sausąsias išrūgas, siekiant pagerinti jį vertingomis mineralinėmis medžiagomis, smulkiadispersiniais (unikaliais) baltymais ir angliavandeniu – laktoze. Ištirti sausųjų išrūgų priedo įtaką rauginimo procesui, fizikinėms – cheminėms surauginto pieno savybėms bei jų kitimą laikymo metu. Darbe ištirta sausųjų išrūgų įtaka rauginto pieno savybėms. Įdėjus sausųjų išrūgų padidėja rauginto pieno biologinė vertė, papildant produktą vertingomis mineralinėmis medžiagomis, smulkiadispersiniais (unikaliais) baltymais ir angliavandeniu – laktoze. Sausųjų išrūgų priedas iki 2 % padidina nepakeičiamų amino rūgščių ir mineralinių medžiagų kiekį. Bendras nepakeičiamų amino rūgščių kiekis padidėjo 1068 mg/l, o bendras mineralinių medžiagų kiekis 1727 mg/l (tame kiekyje kalcio padidėjo 220 mg/l, kalio 280 mg/l, natrio 220 mg/l). Nustatyta, kad sausųjų išrūgų priedas iki 2 % nepakeičia tradicinių rauginto pieno juslinių savybių. Gauta, kad mėginiuose suraugintuose su sausųjų išrūgų priedu padidėja LLRR kiekis, šiek tiek sumažėja rūgštinio gelio klampumas, tačiau padidėja išrūgų imobilizavimo galimybės. Su 1 %... [toliau žr. visą tekstą] / Work size - 48 pages, including 25 pictures, 8 tables. List of literature - 46 sources. The beginning of the work -2006 09 01, the end of the work - 2008 05 13. The article analyzes the influence of dry whey on the properties of sour milk, when the dry whey is added. The biological value of sour milk – daily product of wide usage – increases when it is enriched with valuable mineral substances, small-dispersive (unique) albumens and carbohydrate – lactose. The addition of dry whey up to 2 % increases the amount of irreplaceable amine acids and mineral substances. The total amount of irreplaceable amine acids increased by 1068 mg/l, while total amount of mineral substances increased by 1727 mg/l (including increase of calcium by 220 mg/l, potassium – 280 mg/l, sodium 220 mg/l). It was determined that the addition of dry whey up to 2 % does not change the traditional sensitive properties of sour milk. It resulted that when the dry whey was added, LLRR amount increased in the sour samples, the viscosity of the structure of sour gel decreased a little, but the immobilization possibilities of the whey increased. The addition of dry whey of 1 % results in emission of whey in the process of syneresis (in 2 hours) decreased by 6 %, and 2 % - with 17 %. The determined change of physical-chemical indexes during the storage of sour samples (the amount of LLRR in the beginning of storage up to 2 days increased, and later started to decrease). The change of structure of acid gel happens... [to full text]