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Introduction: Whey proteins have received great attention because of their benefits on skeletal muscle hypertrophy, body fat reduction, performance, appetite regulation, immune system regulation, regulation of the lipid profile and the combat against metabolic stress. In this sense, their importance is often overestimated, leading athletes and physical activity individuals to consume very high doses of protein, without the guarantee of additional benefits. Aim: For 12 weeks quantify the evolution of food intake and total body mass of Wistar rats supplemented with whey proteins with dosages of 2, 4, 6g/kg/day. Materials and methods: Approval protocol of the Ethics Committee on the Use of Animals of the Federal University of Maranhão nº 23115.014424 / 2015-54). An experimental research design was adopted with the rats being randomly distributed in 4 groups: Control Group (C), Supplemented groups (W2, W4, W6); the study was performed with 38 male Rattus novergicus Wistar rats with initial age of 60 days and body mass between 218 and 323 grams; supplementation with whey proteins dissolved in water followed the dosages 2, 4 and 6 g / kg / day supplementation was performed for 12 weeks, daily, three times a day, by volume of 5 ml, with an hour interval between each gavage. Variables were tested for distribution using the Shapiro-Wilk test (P> 0.05). The data of the feed consumption were analyzed by the ANOVA test; the classification variable was the interaction between feed consumption or body mass and supplementation (C, W2, W4, W6); the Tukey post-test was used to determine the statistical differences between the groups (C, W2, W4, W6), GraphPad Prism 7 software was used. Results: The mean intake of rations in the control group did not present a statistically significant difference in relation to the Whey 4 group at weeks 1 (p=0,3450), 2 (p=0,1027), 3 (p=0,1595), 4 (p=0,5572) and 5 (p=0,2539). There was a statistically significant difference in the increase of the tota, Introdução: As whey proteins tem recebido grande atenção por conta de seus benefícios sobre a hipertrofia muscular esquelética, redução de gordura corporal, performance, regulação do apetite, regulação do sistema imunológico, regulação do perfil lipídico e combate ao estresse metabólico. Diante disso, a sua importância muitas vezes é superestimada, levando atletas e indivíduos praticantes de atividades físicas a consumirem doses muito elevadas de proteínas, sem a garantia de benefícios adicionais. Objetivo: Quantificar durante 12 semanas a alteração do consumo de ração e da massa corporal total de ratos wistar suplementados por whey proteins nas doses de 2, 4, 6g/kg/dia. Materiais e Métodos: Protocolo de aprovação da Comissão de Ética no Uso de Animais da Universidade Federal do Maranhão nº 23115.014424/2015-54). Foi adotado delineamento de pesquisa experimental com os ratos sendo distribuídos aleatoriamente em 4 grupos: Grupo Controle (C), Grupos suplementados (W2, W4, W6); o estudo foi realizado com 38 Rattus novergicus machos da linhagem Wistar com idade inicial de 60 dias e massa corporal entre 218 e 323 gramas; a suplementação com whey proteins dissolvidas em água seguiu as dosagens 2, 4 e 6 g/kg/dia a suplementação foi realizada durante 12 semanas, diariamente, três vezes por dia, em volume de 5ml, com uma hora de intervalo entre cada gavagem. As variáveis ​​foram testadas quanto à distribuição utilizando o teste de Shapiro-Wilk (p>0,05). Os dados do consumo de ração, foram analisados pelo teste ANOVA; a variável de classificação foi a interação entre o consumo de ração ou massa corporal e a suplementação (C, W2, W4, W6); o pós-teste de Tukey foi utilizado para determinar as diferenças estatísticas entre os grupos (C, W2, W4, W6), utilizou-se o software GraphPad Prism 7. Resultados: A média de consumo de ração no grupo controle não apresentou diferença estatística significativa em relação ao grupo Whey 4 nas semanas 1 (p=0,3450), 2 (p=0,1027), 3 (p=0,1595), 4

Milk samples were collected from 10 cows, in the colostrum (3-4 days) and mature (90 days) lactation stage, to assess the differential expression of all whey proteins and N-glycoproteins. In total, 240 whey proteins and 315 N-glycosylation sites on 214 glycoproteins were quantified. GO annotations, KEGG pathway analysis, and protein classification were performed to understand the similarities and differences of the biological functions of whey proteins and N-glycoproteins among different lactation stages in bovine milk. Furthermore, differential expression of whey proteins and whey N-glycosylated proteins was found between different lactation stages. The related changes of biological functions in differentially expressed proteins were discussed. For example, the increased frequency of glycosylation on lactoferrin and folate receptor alpha occurring in bovine colostrum may provide protection and stimulate development of the newborn calf. Our study thereby improves understanding of variations of glycosylation sites on milk glycoproteins among lactation stages.

To verify the effect of supplementation of different doses of Whey Proteins for 12 weeks on the gene expression of MTOR, MURF-1, MAFBX and on the alteration of the cellular diameter of the gastrocnemius muscle. Sample: 38 Wistar rats and supplemented for 12 weeks. The white portion of the right gastrocnemius muscle was embedded in Rna Latter solution and stored at -80 ° C and subjected to real-time polymerase chain reaction analysis. The left gastrocnemius muscle was intended for histological analysis. Gene expression of MTOR mRNA had lower statistical significance in the groups of Whey 2, Whey 4, Whey 6 than in the control group, in the order of 100%, 97%, 96%, respectively. Likewise, the gene expression of MURF-1 mRNA had lower statistical significance in the groups of Whey 2, Whey 4, Whey 6 than the control group, in the order of 65%, 75%, 84%, respectively. In line, the gene expression MAFBX mRNA had lower statistical significance in the groups Whey 2, Whey 4, Whey 6 in relation to the control group, in the order of 99%, 97%, 99%, respectively. There was no statistical difference in the cellular area of the gastrocnemius muscle between the groups. Therefore, supplementation of Whey Proteins at doses of 2, 4, 6 g / kg / day for 12 weeks in sedentary animals was not able to increase the gene expression of MTOR mRNA, however, it was able to reduce the gene expression of MURF -1 mRNA, MAFBX mRNA., Verificar o efeito da suplementação de diferentes doses de Whey Proteins por 12 semanas na expressão gênica de MTOR, MURF-1, MAFBX e na alteração do diâmetro celular do músculo gastrocnêmio. Amostra: 38 ratos Wistar e suplementados por 12 semanas. A porção branca do músculo gastrocnêmio direito foi embebida em solução de Rna Latter e armazenada a -80°C e submetida à análise de reação em cadeia da polimerase em tempo real. O músculo gastrocnêmio esquerdo foi destinado à análise histológica. A expressão gênica do mRNA MTOR teve menor significância estatística nos grupos Whey 2, Whey 4, Whey 6 do que no grupo controle, na ordem de 100%, 97%, 96%, respectivamente. Da mesma forma, a expressão gênica do mRNA de MURF-1 teve menor significância estatística nos grupos Whey 2, Whey 4, Whey 6 do que no grupo controle, na ordem de 65%, 75%, 84%, respectivamente. Em linha, a expressão gênica MAFBX mRNA teve menor significância estatística nos grupos Whey 2, Whey 4, Whey 6 em relação ao grupo controle, na ordem de 99%, 97%, 99%, respectivamente. Não houve diferença estatística na área celular do músculo gastrocnêmio entre os grupos. Portanto, a suplementação de Whey Proteins nas doses de 2, 4, 6 g/kg/dia por 12 semanas em animais sedentários não foi capaz de aumentar a expressão gênica de MTOR mRNA, porém, foi capaz de reduzir a expressão gênica de MURF - 1 mRNA, mRNA MAFBX.

Background Extensively hydrolyzed formulas are recommended for the dietary management of infants with cow's milk allergy (CMA). Objectives Hypoallergenicity, growth, and gastrointestinal (GI) tolerability of a new extensively hydrolyzed whey-protein formula (eHWF) in CMA children were assessed. Methods In this prospective, randomized, international, multi-center study (Trial NL3889), 34 children with confirmed CMA (74% IgE-mediated) underwent a double-blind, placebo-controlled food challenge (DBPCFC) with an eHWF developed with non-porcine enzymes, supplemented with prebiotic short-chain galacto- and long-chain fructo-oligosaccharides (0.8 g/L, ratio 9:1), arachidonic acid (0.35/100 g), and docosahexaenoic acid (0.35/100 g). If tolerant to the eHWF, children participated in a 7-day open food challenge with this eHWF. Anthropometrics and GI tolerability were assessed in an optional 16-weeks follow-up. Results Of the 34 children who started the DBPCFC with the eHWF, 25 subjects (19 boys, mean age: 61 weeks, 18 with IgE-mediated CMA) completed the DBPCFC and 7-day open challenge without major protocol deviations and tested negative at both challenges. One child experienced a late moderate eczematous allergic reaction in the optional follow-up period, indicating the need for close monitoring of subjects starting new formula. Weight and length gain followed the World Health Organization growth curves. Changes in frequency and consistency of stools upon test formula intake were transient. Conclusions The newly developed eHWF is a suitable option in CMA treatment as all subjects tolerated the product. This result is in line with the international criteria for hypoallergenicity (American Academy of Pediatrics) that state that more than 90% of CMA children must tolerate the formula. Use of the formula is also associated with normal growth curves and GI tolerability.

In the food and feed industry, protein extraction is commonly performed under acid or basic conditions, combined with heat, in order to increase the extraction yield. Under severe processing conditions, proteins may undergo molecular modifications. Here, the effects of heating (30, 60, 90 °C) at different pH values (2, 7, 9, 11, 13) were evaluated on commercial whey proteins, used as a simplified protein model. The main structure and chemical modifications concerning protein aggregation, hydrolysis, insolubilization, amino acid degradation and racemization were investigated in detail. Using in vitro static models, the degree of protein hydrolysis and the released peptides were determined after the digestive process. Accumulation of molecular modifications was mostly observed after basic pH and high temperatures treatments, together with a marked decrease and modification of the digestibility profile. Instead, protein digestibility increased in neutral and acidic conditions in a temperature-dependent manner, even if some modification in the structure occurs.

Thermal treatment to form functional, soluble whey protein aggregates often generates undesired off-flavours. The aim of the present study was to generate soluble aggregates of whey protein isolates (WPI) at lower temperature than traditionally used by introducing partial hydrolysis of WPI prior to thermal treatment. WPI was partially hydrolyzed either by Bacillus licheniformis protease (BLP) or by a trypsin type protease (TP) at pH 7.0 and 65 °C for 1–10 min prior to thermal treatment at 80 °C for 5–10 min to generate soluble protein aggregates. Partial hydrolysis by BLP and TP induced structural changes and exposure of free thiol groups, but no change of surface hydrophobicity of WPI. After incubation with BLP or TP and thermal treatment, the yield of protein aggregates was 36–48%, which was similar to the reference sample obtained by thermal treatment at 90 °C for 10 min. In addition to non-covalent interactions, disulfide bonds also contributed to the association of protein aggregates. The soluble protein aggregates obtained by BLP partial hydrolysis and thermal treatment, had particle size range of 10–100 nm in radius which was in the same range as observed for the reference sample; and samples obtained by TP treatment had a particle size range of 7–50 nm in radius. However, aggregates obtained by BLP or TP and thermal treatment were not UHT (140 °C/5 s) stable.

UV-B illumination facilitates aggregation of alpha-lactalbumin (alpha-LA) by intramolecular disulfide bond cleavage followed by intermolecular thiol-disulfide exchange reactions. However, long term exposure to UV-B illumination may induce undesired oxidative modifications of amino acid residues in the protein. The purpose of this study was to examine the effect of UV-induced aggregation of apo-alpha-LA (a calcium-depleted form of alpha-LA) under aerobic and anaerobic conditions and by addition of tryptophan (Trp) as a photosensitizer. The addition of Trp to apo-alpha-LA illuminated under anaerobic conditions facilitated the highest level of free thiol release and disulfide-mediated aggregation as compared to without addition of Trp under both anaerobic and aerobic conditions. Addition of Trp under aerobic condition resulted in the lowest level of free thiols and disulfide-mediated aggregation and the aerobic conditions caused oxidation of the free Trp with formation of kynurenine and 5-hydroxy-Trp. Minor levels of the Trp oxidation product, 3-hydroxy-kynurenine (2% converted from Trp), was formed in apo-alpha-LA with added Trp under both aerobic and anaerobic conditions after UV-B treatment.

Human milk is the optimal diet for infant development, but infant milk formula (IMF) must be available as an alternative. To develop high-quality IMF, bovine milk processing is required to ensure microbial safety and to obtain a protein composition that mimics human milk. However, processing can impact the quality of milk proteins, which can influence gastro-intestinal (GI) tolerance by changing digestion, transit time and/or absorption. The aim of this study was to evaluate the impact of structural changes of proteins due to thermal processing on gastro-intestinal tolerance in the immature GI tract. Preterm and near-term piglets received enteral nutrition based on whey protein concentrate (WPC) either mildly pasteurized (MP-WPC) or extensively heated (EH-WPC). Clinical symptoms, transit time and gastric residuals were evaluated. In addition, protein coagulation and protein composition of coagulates formed during in vitro digestion were analyzed in more detail. Characterization of MP-WPC and EH-WPC revealed that mild pasteurization maintained protein nativity and reduced aggregation of β-lactoglobulin and α-lactalbumin, relative to EH-WPC. Mild pasteurization reduced the formation of coagulates during digestion, resulting in reduced gastric residual volume and increased intestinal tract content. In addition, preterm piglets receiving MP-WPC showed reduced mucosal bacterial adherence in the proximal small intestine. Finally, in vitro digestion studies revealed less protein coagulation and lower levels of β-lactoglobulin and α-lactalbumin in the coagulates of MP-WPC compared with EH-WPC. In conclusion, minimal heat treatment of WPC compared with extensive heating promoted GI tolerance in immature piglets, implying that minimal heated WPC could improve the GI tolerance of milk formulas in infants.

Skeletal muscle mass is critical for sport performance and in many pathological conditions. The combination of protein intake and resistance exercise is the most efficient strategy to promote skeletal muscle hypertrophy and remodeling. However, to be really efficient, certain conditions need to be considered. The amount, type and source of proteins do all matter as well as the timing of ingestion and spreading over the whole day. Optimizing those conditions favor a positive net protein balance, which in the long term, may result in muscle mass accretion. Last but not least, it is also essential to take the nutritional status and the exercise training load into consideration when looking for maintenance or gain of skeletal muscle mass.

Virulent lactococcal phages are still a major risk for milk fermentation processes as they may lead to slowdowns and low-quality fermented dairy products, particularly cheeses. Some of the phage control strategies used by the industry rely on heat treatments. Recently, a few Lactococcus lactis phages were found to be highly thermo-resistant. To identify the genetic determinant(s) responsible for the thermal resistance of lactococcal phages, we used the virulent phage CB14 (of the Lactococcus lactis 936 [now Sk1virus] phage group) to select for phage mutants with increased heat stability. By treating phage CB14 to successive low and high temperatures, we were able to select two CB14 derivatives with increased heat stability. Sequencing of their genome revealed the same nucleotide sequences as the wild-type phage CB14, except for a same-sized deletion (120 bp) in the gene coding for the tape measure protein (TMP) of each phage mutant, but at a different position. The TMP protein sequences of these mutant phages were compared with their homologues in other wild-type L. lactis phages with a wide diversity in heat stability. Comparative analysis showed that the same nucleotide deletion appears to have also occurred in the gene coding for the TMP of highly thermo-resistant lactococcal phages P1532 and P680. We propose that the TMP is, in part, responsible for the heat stability of the highly predominant lactococcal phages of the Sk1virus group. IMPORTANCE Virulent lactococcal phages still represent a major risk for milk fermentation as they may lead to slowdowns and low-quality fermented dairy products. Heat treatment is one of the most commonly used methods to control these virulent phages in cheese by-products. Recently, a few Lactococcus lactis phages, members of the Sk1virus group, have emerged with high thermal stability. To our knowledge, the genetic determinant(s) responsible for this thermal resistance in lactococcal phages is unknown. A better understanding of th

Background: As the demand for “clean label emulsions” and natural emulsifiers is increasing, whey proteins havea big potency to be used as an emulsifier in food emulsions. However, in order to enable their application, whey proteins should withstand high temperature processing. Hence, the limited heat stability of whey proteins is a major drawback: they are highly heat labile and thus prone to heat induced protein denaturation and aggregation. As this phenomenon highly impacts their functionality, it is of utmost importance to increase the heat stability of whey proteins to broaden their application in the food industry, which requires a thorough knowledge of the heat stability properties of whey proteins. Scope and approach: To better understand the heat stabilizing activity of whey protein-polysaccharides conjugates, studies on the heat stability of whey proteins and whey protein stabilized emulsions, as well as approaches to improve their heat stability, especially using the dry heat treatment method are reviewed. Key findings and conclusions: Chemical modification by combining whey proteins and polysaccharides has been reported to successfully improve the heat stability of the obtained conjugates. Hence, this new whey protein-polysaccharide material is promising to be used as a natural emulsifier.

Whey proteins (WP) were replaced with rapeseed proteins (RP) at various protein mixing ratios at neutral pH and ionic strength of 150 mM. Protein gels were formed at 95 °C and another temperature of 80 °C, below the denaturation temperature of RP, to understand the importance of whether RP gelled or not for changes in rheological properties in mixed gels. Gels were analyzed for their microstructure, rheological responses (e.g. G’) and water holding (maximum amount of exuded water (Amax) and ease with which water can be exuded (k)). The rheological responses obtained for mixed gels was compared to the ones of the single systems at the corresponding concentrations to understand the importance of the rheological moduli of the single systems to the modulus of the mixed gel and to enable the quantification of synergistic stiffening (S = G΄mixture/(G΄WP + G΄RP)). For gels formed at 95 °C a broader window for synergistic stiffening was formed compared to gels formed at 80 °C. Synergistic stiffening occurred when gel coarseness decreased and/or when the differences between the moduli of the individual protein gels were minimized. Water holding properties of mixed gels were tailored due to changes in the gel microstructure or due to synergistic stiffening. The behavior of k as a function of protein mixing ratio in mixed gels was similar to the behavior of gel stiffness. The decrease of k correlated well with an increase in gel stiffness. Gel coarseness and gel stiffness were inextricably linked in regards to their importance for changes in Amax.

Background A chronic low-grade infammatory profle (CLIP) is associated with sarcopenia in older adults. Protein and Vitamin (Vit)D have immune-modulatory potential, but evidence for efects of nutritional supplementation on CLIP is limited. Aim To investigate whether 13 weeks of nutritional supplementation of VitD and leucine-enriched whey protein afected CLIP in subjects enrolled in the PROVIDE-study, as a secondary analysis. Methods Sarcopenic adults (low skeletal muscle mass) aged ≥ 65 years with mobility limitations (Short Physical Performance Battery 4–9) and a body mass index of 20–30 kg/m2 were randomly allocated to two daily servings of active (n=137, including 20 g of whey protein, 3 g of leucine and 800 IU VitD) or isocaloric control product (n=151) for a double-blind period of 13 weeks. At baseline and after 13 weeks, circulating interleukin (IL)-8, IL-1 receptor antagonist (RA), soluble tumor-necrosis-factor receptor (sTNFR)1, IL-6, high-sensitivity C-reactive protein, pre-albumin and 25-hydroxyvitamin(OH) D were measured. Data-analysis included repeated measures analysis of covariance (corrected for dietary VitD intake) and linear regression. Results IL-6 and IL-1Ra serum levels showed overall increases after 13 weeks (p=0.006 and p<0.001, respectively). For IL-6 a signifcant time × treatment interaction (p=0.046) was observed, with no signifcant change over time in the active group (p=0.155) compared to control (signifcant increase p=0.012). IL-8 showed an overall signifcant decrease (p=0.03). The change in pre-albumin was a signifcant predictor for changes in IL-6 after 13 weeks. Conclusions We conclude that 13 weeks of nutritional supplementation with VitD and leucine-enriched whey protein may attenuate the progression of CLIP in older sarcopenic persons with mobility limitations.

Bovine whey proteins are highly valued dairy ingredients. This is primarily due to their amino acid content, digestibility, bioactivities and their processing characteristics. One of the reported bioactivities of whey proteins is antioxidant activity. Numerous dietary intervention trials with humans and animals indicate that consumption of whey products can modulate redox biomarkers to reduce oxidative stress. This bioactivity has in part been assigned to whey peptides using a range of biochemical or cellular assays in vitro. Superimposing whey peptide sequences from gastrointestinal samples, with whey peptides proven to be antioxidant in vitro, allows us to propose peptides from whey likely to exhibit antioxidant activity in the diet. However, whey proteins themselves are targets of oxidation during processing particularly when exposed to high thermal loads and/or extensive processing (e.g. infant formula manufacture). Oxidative damage of whey proteins can be selective with regard to the residues that are modified and are associated with the degree of protein unfolding, with alpha-Lactalbumin more susceptible than beta-Lactoglobulin. Such oxidative damage may have adverse effects on human health. This review summarises how whey proteins can modulate cellular redox pathways and conversely how whey proteins can be oxidised during processing. Given the extensive processing steps that whey proteins are often subjected to, we conclude that oxidation during processing is likely to compromise the positive health attributes associated with whey proteins.

Whey proteins are extensively used as nutritional supplements but have so far not been investigated as co-formers for amorphous solid dispersions (ASD) to enhance the solubility and dissolution rate of poorly water soluble drugs. In this study, whey protein isolate (WPI) and whey protein hydrolysate (WPH) were each mixed with three poorly water soluble drugs (indomethacin: IND, carvedilol: CAR and furosemide: FUR) and prepared as ASDs at 50% (w/w) drug loading using vibrational ball milling. Subsequently, solid state characteristics, dissolution rate and physical stability of the obtained samples were analyzed. All ASDs showed a significant increase in their glass transition temperatures, as well as faster dissolution rates and higher apparent solubilities compared to both the respective pure crystalline and amorphous drugs. The saturation solubility of the drugs was increased in the presence of the whey proteins, and the investigated ASDs showed supersaturation by attaining higher drug concentrations compared to the respective saturation solubilities. Upon storage, ASDs containing IND were found to be physically stable for at least 27 months, whereas, ASDs containing CAR or FUR were stable for about 8 months and 17 months, respectively. This was a tremendous increase in physical stability compared to the pure amorphous drugs which recrystallized within less than one week. Overall, WPI and WPH proved to be promising co-formers and amorphous stabilizers in ASD formulations.

Interest in supplementing food with iron to counteract dietary deficiencies has been on the rise in recent years. A major challenge is the pro‐oxidant activity of soluble iron, which compromises the chemical stability of the enriched food products. This problem could be mitigated by encapsulating iron, to physically keep it separated from oxidizable substrates, such as unsaturated fatty acids. In the present work, the physical and chemical stability of surfactant‐ or protein‐stabilized oil‐in‐water emulsions fortified with iron was investigated.

Camel milk has been used for its nutritional and therapeutic benefits since ancient times. Previously, whole camel milk and casein proteins have been explored for their potential bioactive properties. However, studies on camel milk whey proteins and their hydrolysates are still scarce. Hence, the aim of the proposed thesis was to evaluate camel whey proteins and their hydrolysates for potential bioactivities like antioxidant, antimicrobial, antidiabetic, antihypertensive, and anti-cholesterol properties. Production of the hydrolysates was carried out using three digestive enzymes – pepsin, trypsin and chymotrypsin for 3 and 6 h of hydrolysis time. Hydrolysates were characterized by degree of hydrolysis (DH) and reversed-phase high-performance liquid chromatography (RP-HPLC). In vitro experiments were performed to evaluate the bioactive properties of different camel whey protein hydrolysates (CWPHs). Results revealed that CWPHs showed DH ranging from 11 to 47.5%, with chymotrypsin (6 h) and trypsin (3 h) exhibiting highest and lowest DH, respectively. RP-HPLC analysis revealed that α-lactalbumin underwent complete degradation and newer shorter peptides were generated. Chymotrypsin generated CWPHs demonstrated highest 2, 2-diphenyl-1-picrylhydrazy (DPPH) and 2,2'-azino-bis (3- ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, while trypsin generated CWPHs displayed highest metal chelating activity. CWPHs showed markedly greater antimicrobial activity than un-hydrolyzed whey against all pathogenic bacteria tested. Anti-cholesterol property via inhibition of cholesterol esterase and lipase, and antihypertensive property via angiotensin-converting enzyme (ACE) inhibition were found to be highest in pepsin (6 h) and (3 h) generated CWPHs, respectively. CWPHs also displayed potential antidiabetic activity compared to intact whey proteins, where pepsin and chymotrypsin generated CWPHs showed higher inhibition of dipeptidyl peptidase-IV

Virulent lactococcal phages are still a major risk for milk fermentation processes as they may lead to slowdowns and low-quality fermented dairy products, particularly cheeses. Some of the phage control strategies used by the industry rely on heat treatments. Recently, a few Lactococcus lactis phages were found to be highly thermoresistant. To identify the genetic determinant(s) responsible for the thermal resistance of lactococcal phages, we used the virulent phage CB14 (of the Lactococcus lactis 936 [now Sk1virus] phage group) to select for phage mutants with increased heat stability. By treating phage CB14 to successive low and high temperatures, we were able to select two CB14 derivatives with increased heat stability. Sequencing of their genome revealed the same nucleotide sequences as the wild-type phage CB14, except for a same-sized deletion (120 bp) in the gene coding for the tape measure protein (TMP) of each phage mutant, but at a different position. The TMP protein sequences of these mutant phages were compared with their homologues in other wild-type L. lactis phages with a wide diversity in heat stability. Comparative analysis showed that the same nucleotide deletion appears to have also occurred in the gene coding for the TMP of highly thermo-resistant lactococcal phages P1532 and P680. We propose that the TMP is, in part, responsible for the heat stability of the highly predominant lactococcal phages of the Sk1virus group. IMPORTANCE : Virulent lactococcal phages still represent a major risk for milk fermentation as they may lead to slowdowns and low-quality fermented dairy products. Heat treatment is one of the most commonly used methods to control these virulent phages in cheese by-products. Recently, a few Lactococcus lactis phages, members of the Sk1virus group, have emerged with high thermal stability. To our knowledge, the genetic determinant(s) responsible for this thermal resistance in lactococcal phages is unknown. A better underst

peer-reviewed, Angiotensin converting enzyme (ACE) and dipeptidyl peptidase-IV (DPP-IV) inhibitory activities of crosslinked and non-cross-linked sodium caseinate (NaCN) hydrolysates were studied. Three different samples were generated: NaCN hydrolysed with Prolyve 1000 (TM) (Prolyve), NaCN cross-linked with transglutaminase (TGase) pre-Prolyve hydrolysis and NaCN cross-linked post-Prolyve hydrolysis. Gel filtration and reverse phase HPLC analysis of the resulting samples indicated that the hydrolysates had similar peptide profiles. Hydrolysates showed higher (p 0.05) differences in activity were found between cross-linked and non-cross-linked hydrolysate samples. Hydrolysate IC50 values for ACE and DPP-IV inhibition ranged from 0.10 to 0.17 mg mL(-1) and 0.85-1.18 mg mL(-1), respectively. Simulated gastrointestinal digestion had no significant (p > 0.05) effect on the bioactivities of the hydrolysates. The results demonstrated that incubation with TGase before or after NaCN hydrolysis with Prolyve had no effect on ACE or DPP-IV inhibitory activities. (c) 2017 Elsevier Ltd. All rights reserved., peer-reviewed

Skim milk ultrafiltration (UF) is an important dairy process operation in which milk proteins are preferentially concentrated for downstream manufacturing of cheese and milk protein concentrates (MPC), and also for protein standardisation. However its operational efficiency is impacted by the accumulation of retained particles at the membrane surface (concentration polarisation, CP) and the irreversible deposition of particles onto the membrane surface and in membrane pores (fouling). CP and fouling ultimately result in lower throughput (flux decline), alterations in product quality, significant operational downtime and vast consumption of water and cleaning chemicals. Development of effective optimisation strategies and technologies for the mitigation or prevention of CP and fouling requires the mastery of these flux decline phenomena. However CP and fouling are still not completely understood despite over 30 years of industrial application, owing partly to the complex physicochemical nature of skim milk. This thesis aims to extend our current understanding of CP and fouling in skim milk UF. Specific investigations include the influence of processing temperature and diafiltration (DF) on CP and fouling in skim milk UF, characterisation of the osmotic compressibility of skim milk, and a visual assessment of gel formation during skim milk UF. A comprehensive examination of skim milk UF behaviour as a function of processing temperature (between 10-50 °C) showed, for the first time, that fouling at 10 °C is shown to be primarily proteinaceous, consistent with fouling at 50 °C (mainly alpha-lactalbumin, a-LA, and peptides). This provides a validation of existing fouling observations at 50 °C for UF at 10 °C, for which there are very few fouling investigations despite its widespread use. Despite higher fluxes, higher processing temperatures led to a greater magnitude and rate of fouling. This was found to be caused by increased pore blocking by a-LA and deposition/adsorp

This chapter discusses various types of whey cheeses such as, Anari cheese, Anthotyros cheese and Manouri Protected Designation of Origin (PDO) cheese. Anari is a whey cheese produced during the manufacture of Halloumi cheese. Fresh Anari is a soft, high-moisture, fragile cheese, with a very mild nutty sweet flavour, and it can be sold in vacuum packs either slightly salted or not. Anari cheese is usually dried, under cold air streams, in specially designed drying rooms until it becomes hard and easy to grate. Anthotyros cheese has a compact, closed body and a typical mild pleasant flavour. Manouri is a whey cheese which is manufactured in Thessaly, Western and Central Macedonia. Manouri cheese has a compact, closed body and a rich flavour with creamy, fatty notes. Mesost and Messmör are unripened whey cheeses that differ from each other only in water content. Mesost and Messmör contain milk sugar, lactose, whey proteins and sometimes milk fat.

Diabetic dyslipidemia with elevated postprandial triglyceride (TG) responses is characteristic in type 2 diabetes (T2D). Diet and meal timing can modify postprandial lipemia (PPL). The impact of a pre-meal of whey proteins (WP) on lipid metabolism is unidentified. We determined whether a WP pre-meal prior to a fat-rich meal influences TG and apolipoprotein B-48 (ApoB-48) responses differentially in patients with and without T2D. Two matched groups of 12 subjects with and without T2D accomplished an acute, randomized, cross-over trial. A pre-meal of WP (20 g) or water (control) was consumed 15 min before a fat-rich meal (supplemented with 20 g WP in case of water pre-meal). Postprandial responses were examined during a 360-min period. A WP pre-meal significantly increased postprandial concentrations of insulin (P< 0.0001), glucagon (P< 0.0001) and glucose-dependent insulinotropic peptide (GIP) (P< 0.0001) in subjects with and without T2D. We detected no effects of the WP pre-meal on TG, ApoB-48, or non-esterified fatty acids (NEFA) responses to the fat-rich meal in either group. Paracetamol absorption i.e. gastric emptying was delayed by the WP pre-meal (P= 0.039). In conclusion, the WP pre-meal induced similar hormone and lipid responses in subjects with and without T2D. Thus, the WP pre-meal enhanced insulin, glucagon and GIP responses but did not influence lipid or glucose responses. In addition, we demonstrated that a WP pre-meal reduced gastric emptying in both groups.

peer-reviewed, Inhibition of dipeptidyl peptidase-IV (DPP-IV) is used as a means to regulate post-prandial serum glucose in type 2 diabetics. The effect of drug (Sitagliptin®)/peptide and binary peptide mixtures on DPP-IV inhibition was studied using an isobole approach. Five peptides (Ile-Pro-Ile-Gln-Tyr, Trp-Lys, Trp-Pro, Trp-Arg and Trp-Leu), having DPP-IV half maximum inhibitory concentration values (IC₅₀)<60 μM and reported to act through different inhibition mechanisms, were investigated. The dose response relationship of Sitagliptin : peptide (1:0, 0:1, 1:852, 1:426 and 1:1704 on a molar basis) and binary Ile-Pro-Ile-Gln-Tyr : peptide (1:0, 0:1, 1:1, 1:2 and 2:1 on a molar basis) mixtures for DPP-IV inhibition was characterised. Isobolographic analysis showed, in most instances, an additive effect on DPP-IV inhibition. However, a synergistic effect was observed with two Sitagliptin:Ile-Pro-Ile-Gln-Tyr (1:426 and 1:852) mixtures and an antagonistic effect was seen with one Sitagliptin : Trp-Pro (1:852) mixture, and three binary peptide mixtures (Ile-Pro-Ile-Gln-Tyr : Trp-Lys (1:1 and 2:1) and Ile-Pro-Ile-Gln-Tyr:Trp-Leu (1:2)). The results show that Sitagliptin and food protein-derived peptides can interact, thereby enhancing overall DPP-IV inhibition. Combination of Sitagliptin with food protein-derived peptides may help in reducing drug dosage and possible associated side-effects., ACCEPTED, peer-reviewed

ObjectiveThe objective of this study was to determine if clinical dynamic PET/CT imaging with 11C-L-methyl-methionine (11C-MET) in healthy older women can provide an estimate of tissue-level post-absorptive and post-prandial skeletal muscle protein synthesis that is consistent with the more traditional method of calculating fractional synthesis rate (FSR) of muscle protein synthesis from skeletal muscle biopsies obtained during an infusion of L-[ring 13C6] phenylalanine (13C6-Phe).MethodsHealthy older women (73 ± 5 years) completed both dynamic PET/CT imaging with 11C-MET and a stable isotope infusion of 13C6-Phe with biopsies to measure the skeletal muscle protein synthetic response to 25 g of a whey protein supplement. Graphical estimation of the Patlak coefficient Ki from analysis of the dynamic PET/CT images was employed as a measure of incorporation of 11 C-MET in the mid-thigh muscle bundle.ResultsPost-prandial values [mean ± standard error of the mean (SEM)] were higher than post-absorptive values for both Ki (0.0095 ± 0.001 vs. 0.00785 ± 0.001 min-1, p < 0.05) and FSR (0.083 ± 0.008 vs. 0.049 ± 0.006%/h, p < 0.001) in response to the whey protein supplement. The percent increase in Ki and FSR in response to the whey protein supplement was significantly correlated (r = 0.79, p = 0.015).ConclusionsDynamic PET/CT imaging with 11C-MET provides an estimate of the post-prandial anabolic response that is consistent with a traditional, invasive stable isotope, and muscle biopsy approach. These results support the potential future use of 11C-MET imaging as a non-invasive method for assessing conditions affecting skeletal muscle protein synthesis.

peer-reviewed, Enzymatic hydrolysis of whey protein (WP) was carried out under pH-controlled and non pH-controlled conditions using papain and a microbial-derived alternative (papain-like activity). The impact of such conditions on physicochemical and bioactive properties was assessed. WP hydrolysates (WPH) generated with the same enzyme displayed similar degree of hydrolysis. However, their reverse-phase liquid chromatograph mass spectrometry peptide profiles differed. A significantly higher oxygen radical absorbance capacity (ORAC) value was obtained for WP hydrolysed with papain at constant pH of 7.0 compared to the associated WPH generated without pH regulation. In contrast, there was no significant effect of pH regulation on dipeptidyl peptidase IV (DPP-IV) properties. WP hydrolysed with papain-like activity under pH regulation at 7.0 displayed higher ORAC activity and DPP-IV inhibitory properties compared to the associated WPH generated without pH regulation. This study has demonstrated that pH conditions during WPH generation may impact on peptide release and therefore on WPH bioactive properties. (c) 2015 Elsevier Ltd. All rights reserved., ACCEPTED, peer-reviewed

peer-reviewed, Milk protein hydrolysates generated with different starting substrates, including sodium caseinate (NaCN), acid casein (Acid CN), skim milk powder (SMP) and glycomacropeptide (GMP) were demonstrated to behave as serotonin 2C (5-HT2C) receptor agonists. The 5-HT2C receptor activating potential of NaCN hydrolysates correlated with an increased protein hydrolysis, most likely due to enhanced release of bioactive peptides over the time course of hydrolysis. In its unhydrolysed form, GMP was the only starting substrate showing 5-HT2C serotonin receptor agonist activity. The 5-HT2C serotonin receptor agonist activity of its corresponding hydrolysate (GMPH-240 min) was significantly higher (P < 0.05). Fractionation of the 240 min NaCNH using ultrafiltration (UF), solid-phase extraction (SPE), semipreparative reverse-phase high performance liquid chromatography (RP-HPLC) and isoelectric focusing (IEF) was carried out. Characterisation of the fractions obtained shows that the bioactive peptides had a relatively low molecular mass (<1 kDa), were hydrophobic in nature and had a pI between 8.6 and 13.2. These different physicochemical characteristics together with the stability of NaCNH-240 min to simulated intestinal digestion, allow prediction of a favourable outcome regarding the bioavailability of the bioactive peptides therein. These results reinforce the potential of milk-derived bioactive peptides to be developed into functional foods targeted at 5-HT2C receptor modulation., ACCEPTED, peer-reviewed

Introduction: The protein supplements and branched-chain amino acids (BCAAs) are consumed by all kinds of people to obtain a number of physiological and metabolic effects reversing improvements in performance and fast recovery among others. Objective: To perform an exhaustive review of the most recent scientific publications where it has studied the effects of consuming protein supplements and BCAAs in resistance training in different physiological and metabolic parameters. Material and Methods: Descriptive literature review. A specific keyword search was conducted in the PubMed database and snowball strategy. Inclusion criteria: studies in humans of ≥18 without pathology, meta-analysis, systematic reviews and randomized controlled trials in English and Spanish related to the consumption of protein supplements and/or BCAAs in resistance training and its effects on muscle damage, anabolic response in muscle recovery, gain muscle mass and strength, body composition and fatigue. Results: Out of the 64 studies identified by the search equation, 20 met the inclusion criteria. The arithmetic mean of the participating subjects is equal to (30.59±24.47). Conclusions: Protein supplements may have a positive effect on increasing muscle mass and performance, but further studies are needed to clarify their potential benefit on body composition, fatigue, attenuation and reducing pain and muscle damage. Leucine has an effect on the increase of muscle mass and its function in the elderly. BCAAs could act on the attenuation of central fatigue and on performance improvement., Introducción: Los suplementos de proteína y aminoácidos de cadena ramificada (BCAAs) son consumidos por la población buscando una serie de efectos fisiológicos y metabólicos sobre el rendimiento y recuperación, entre otros. Objetivos: Revisión de las publicaciones más recientes que estudien los efectos del consumo de suplementos de proteína y BCAAs en entrenamiento de fuerza en diferentes parámetros fisiológicos y metabólicos. Material y métodos: Estudio descriptivo de revisión bibliográfica. Se realizó una búsqueda específica de palabras clave en la base de datos PubMed y estrategia de bola de nieve. Criterios de inclusión: estudios realizados en humanos de ≥ 18 años sin patología, metaanálisis, revisiones sistemáticas y ensayos clínicos controlados aleatorizados en inglés y español relacionados con el consumo de suplementos de proteína y/o BCAAs en entrenamiento de fuerza y sus efectos sobre el daño muscular, respuesta anabólica en la recuperación muscular, ganancia de masa muscular y fuerza, composición corporal y fatiga. Resultados: 64 estudios identificados mediante la ecuación de búsqueda, 20 cumplieron con los criterios de inclusión. La media aritmética de los sujetos participantes fue igual a (30,59 ± 24,47). Conclusiones: Los suplementos de proteína podrían tener un efecto positivo en el aumento del rendimiento y la masa muscular, pero hacen falta más estudios para esclarecer su posible beneficio sobre la composición corporal, la fatiga, la atenuación y reducción del dolor y daño muscular. La leucina tiene efecto en el aumento de la masa muscular y su función en población de edad avanzada. Los BCAAs podrían actuar sobre la atenuación de la fatiga central y en la mejora del rendimiento.

BALB/c mice were used to assess the ability of a whey protein hydrolysate obtained by pepsin treatment under high pressure (400 MPa, 37 °C, 30 min, HWP), to induce anaphylaxis, antibody production and cytokine responses in comparison with the whey protein isolate (WP) from which it is derived. HWP did not contain intact allergens and 50% of its peptides ranged between 10 and 3 kDa. Challenge with HWP did not induce clinical signs, body temperature changes or release of mast cell proteinase-1 in mice sensitized to WP. Immunization of mice with HWP did not produce WP-specific antibodies or allergic reactions upon HWP or WP challenge and thus, it can be considered hypoallergenic. However, HWP stimulated Th2 responses in splenocytes from sensitized mice. These characteristics make HWP a good candidate to be used in the management of milk allergy in diagnosed patients or to induce tolerance to whey proteins.

Proteomics of human milk has been used to identify the comprehensive cargo of proteins involved in immune and cellular function. Very little is known about the effects of gestational diabetes mellitus (GDM) on lactation and breast milk components. The objective of the current study was to examine the effect of GDM on the expression of proteins in the whey fraction of human colostrum. Colostrum was collected from women who were diagnosed with (n = 6) or without (n = 12) GDM at weeks 24-28 in pregnancy. Colostral whey was analyzed for protein abundances using high-resolution, high-mass accuracy liquid chromatography tandem mass spectrometry. A total of 601 proteins were identified, of which 260 were quantified using label free spectral counting. Orthogonal partial least-squares discriminant analysis identified 27 proteins that best predict GDM. The power law global error model corrected for multiple testing was used to confirm that 10 of the 27 proteins were also statistically significantly different between women with versus without GDM. The identified changes in protein expression suggest that diabetes mellitus during pregnancy has consequences on human colostral proteins involved in immunity and nutrition.

High intensity ultrasound (HIUS) can promote Maillard reaction (MR). Macromolecular crowding conditions accelerate reactions and stabilise protein structure. The aim of this study was to investigate if combined application of ultrasound and macromolecular crowding can improve efficiency of MR. The presence of crowding agent (polyethylene glycol) significantly increased ultrasound-induced whey protein (WP) glycation by arabinose. An increase in glycation efficiency results only in slight change of WP structure. Macromolecular crowding intensifies oxidative modifications of WP, as well as formation of amyloid-like structures by enhancement of MR. Solubility at different pH, thermal stability and antioxidative capacity of glycated WP were increased, especially in the presence of crowding agent, compared to sonicated nonglycated proteins. The application of HIUS under crowding conditions can be a new approach for enhancement of reactions in general, enabling short processing time and mild conditions, while preserving protein structure and minimising protein aggregation. (C) 2015 Elsevier Ltd. All rights reserved.

Biopolymer carriers are widely used for immobilization of the bioactive compounds and different type of the cells. The aim of this study was to analyze influence of whey proteins addition on mechanical strength of Ca-alginate beads and survival of probiotic bacteria during the whey fermentation process. Mechanical stability of beads was analyzed up to 30% of bead's deformation using compression method between two flat plates. The fermentation was carried out with probiotic starter culture ABY-6 until pH=4.6. The results indicate that the addition of whey proteins in alginate solution increases strength of the beads after fermentation in comparison with alginate beads without proteins and extends the shelf life of products through improving the viability of probiotics., Biopolimerni nosači su najčešće korišćenih nosači za imobilizaciju bioaktivnih jedinjenja i različite vrste ćelija. Cilj ovog istraživanja je bila analiza uticaja dodatka proteina surutke na mehaničku čvrstoću kalcijum alginatnih čestica i preživljavanje probiotskih bakterija tokom procesa fermentacije surutke. Mehanička stabilnost nosača je analizirana do 30% deformacije čestica metodom kompresije između dve ravne ploče. Fermentacija se odvijala pomoću probiotiske starter kulture ABY-6 do vrednosti pH = 4.6. Rezultati ukazuju da dodatak proteina surutke u alginatni rastvor povećava čvsrtoću čestica nakon fermentacije u poređenju sa alginatnim česticama bez proteina i produžava rok trajanja proizvoda kroz unapređenje preživljavanja probiotskih bakterija .

Oil-in-water (o/w) emulsions are commonly converted into solid-like powders in order to improve their physical and chemical stabilities. The aim of this study was to investigate whether whey protein/polysaccharide-stabilized o/w emulsions could be converted into stable oil powders by means of freeze-drying. Moreover, during this study, the effects of pH and polymer type on release and trans(dermal) delivery of salicylic acid, a model drug, from these oil powders were investigated and compared to those of the respective template emulsions and redispersed oil powders. Physical characterization of the various formulations was performed, such as droplet size analysis and oil leakage, and relationships drawn with regards to release and trans(dermal) delivery. The experimental outcomes revealed that the oil powders could be redispersed in water without changing the release characteristics of salicylic acid. pH and polymer type affected the release of salicylic acid from the oil powders, template emulsions, and redispersed powders similarly. Contrary, the transdermal delivery from the oil powders and from their respective redispersed oil powders was differently affected by pH and polymer type. It was hypothesized that the release had been influenced by the electrostatic interactions between salicylic acid and emulsifiers, whereas the transdermal performance could have been determined by the particle or aggregate sizes of the formulations

This study investigated the in-vitro digestibility of cold-set whey protein (WP) microgels prepared by two gelation methods (external and internal) containing lipids (0%, 10% or 20% w/w). The incorporation of lipids into these matrices achieved higher entrapment of the bioactive vitamin riboflavin, as well as significant reductions in rates of both the digestion of the protein matrix, and the subsequent diffusion of the water-soluble bioactive. A biexponential model accounted for the contribution of digestion- and diffusion-driven mechanisms in describing the release of riboflavin into enzyme containing simulated gastrointestinal fluids. In particular, for external gelation microgels, as the lipid load within the matrices increased, the contribution of a faster diffusion-driven release was almost completely negated by a slower digestion-assisted release. Lipid loads provided a composite matrix capable of alternating from a burst to a sustained release of bioactive.

Aqueous 6.86% whey protein concentrate 35 (WPC 35) solution was heated at the temperature of 70°C for 10, 15 and 20 minutes respectively to quantify the amount of native protein, soluble protein aggregates and insoluble protein aggregates in the heated samples. The serums of the emulsions formed from the different heated samples were also analyzed for percentages of native proteins and aggregated proteins using Dumas combustion method. The aim of this work was to improve the knowledge on the functionality of WPC 35 with a heat treatment of 70°C at varied period of time. The results show that there was native protein fraction of 76.6%, 14.4% soluble protein fraction and 9% insoluble protein aggregates when aqueous 6.86% WPC 35 solution was heated at 70°C for 10 minutes. Emulsion formed from the heated sample contains 78.2% native protein in its serum after centrifugation. With a heat treatment of the same sample at 70°C for 15 minutes, the content of native protein fraction was 73%, 8.3% soluble protein fraction and 18.7% insoluble protein aggregates. The resulting emulsion from this heat treatment had 66.9% native protein in its serum after centrifugation. Heat treatment of aqueous 6.86% WPC 35 at 70°C for 20 minutes contains 80.43% of native proteins, 5.6% of soluble protein and 13.97% insoluble proteins. The emulsion prepared from the heated sample has 81.7% native proteins in its serum. Effect of some other processing conditions such as homogenization and length of storage of whey protein dispersion were also examined.

Bakalářská práce se zabývá chemickým složením kravského mléka. Práce je zaměřena na stručnou charakteristiku jednotlivých skupin látek, které se vyskytují v mléce (bílkoviny, lipidy, sacharidy, minerální látky, vitamíny, enzymy), a na možnosti jejich analýzy. Dále je v práci srovnáno mléka kravského s jinými druhy mléka. Poslední kapitola pojednává o laktózové intoleranci a alergii na bílkovinu kravského mléka., The bachelor thesis deals with the chemical composition of cows? milk. It is focused on the brief characterization of groups of the substances, which are present in milk (proteins, lipids, carbohydrates, minerals, vitamins, enzymes) and the possibilities of their analysis. The study also compared the cows? milk with other types of milk. The last chapter deals with lactose intolerance and allergy to cows? milk protein., Katedra analytické chemie, Student zodpověděl dotazy komise a obhájil bakalářskou práci.

A proline-rich peptide product prepared from bovine whey protein that was enriched in several hydrophobic amino acids including proline (whey proline-rich peptide, wPRP) was shown to modulate the folding pathway of human amyloid beta peptide 1-42 (Aβ42) into oligomers. Concentration-dependent changes in ThT-binding to Ab42 by wPRP indicated suppression of oligomerisation, that was supported by Transmission Electron Microscopy. Suppression of β-sheet and specifically, anti-parallel β-sheet structures by wPRP was demonstrated by ATR-FTIR spectroscopy, where evidence for capacity of wPRP to dissociate pre-existing β-sheet structures in Aβ42 was also apparent. Suppression of anti-parallel β-sheets of oligomeric Aβ42 was associated with rescue of yeast and SH-SY5Y neuronal cells providing important evidence for the association between anti-parallel β-sheet structure and oligomer toxicity. It was proposed that the interaction of wPRP with Aβ42 interfered with the anti-parallel folding pathway of oligomeric Aβ42 and ultimately produced 'off-pathway' structures of lowered total β-sheet content, with attenuated cellular toxicity.

[ ES] Numerosas investigaciones han respaldado que una dieta de alto contenido proteico puede promover la pérdida de peso y prevenir su ganancia posterior. Por ello, la incorporación de este ingrediente con propiedades saciantes en los alimentos ha tenido auge en los últimos años. En el presente trabajo se evaluó el efecto de la reformulación de tartas de queso (CE), reduciendo su contenido en grasa láctea al 50% (CD) e incorporando aislado proteico de lactosuero a tres concentraciones diferentes (P1=2%, P2=3% y P3=4%), sobre las propiedades de color, textura y sensoriales del producto final. Además se estudió su estabilidad con el tiempo de almacenamiento durante 14 días bajo condiciones de refrigeración. Se utilizaron métodos instrumentales para la determinación de color (parámetros CieL*a*b*) y textura (análisis de doble compresión TPA) y el método de flash profiling para la evaluación sensorial de las muestras. P3 obtuvo las mayores diferencias en cuanto a color y textura instrumental con respecto a CD y las mayores diferencias en la evaluación sensorial con respecto a CE y CD. Los resultados instrumentales corroboraron la tendencia de los resultados sensoriales. Los valores medios para tono disminuyeron en CD, P1, P2 y P3 y sus valores medios de dureza, cohesividad y masticabilidad aumentaron. Se observó en P3 la mayor percepción de los atributos sensoriales dureza, intensidad del color amarillo y astringencia. Durante el tiempo de almacenamiento, todas las muestras disminuyeron sus valores medios de luminosidad, croma y cohesividad y P1, P2 y P3 también aumentaron sus valores medios de elasticidad, [ CA ] Nombroses investigacions han afirmat que una dieta d'alt contingunt proteic pot promoure la pèrdua de pes i previndre el seu guany posterior; per això, la incorporació d'est ingrediente amb propietats saciants en els aliments ha tingut auge en els últims anys. En el present treball es va evaluar l'efecte de la reformulació de tortades de formatge (CE), reduint el seu contingunt en greix lacti al 50% (CD) i incorporant aïllat proteic de lactosuero a tres concentracions diferents (P1=2%, P2=3% i P3=4%), sobres les propietats de color i textura instrumentals i sensorials del producte final i la seua estabilitat amb el temps d¿emmagatzemament durant 14 dies baix condicions de refrigeració. Es van utilitzar mètodes instrumentals per a la determinació de color (parámetres CieL*a*b*) i textura (anàlisi de doble compressió TPA) i el mètode de flash profiling per a l'avaluació sensorial de les postres. P3 va obtindre les majors diferències quant a color i textura instrumental respecte a CE i les majors diferències en l'avaluació sensorial respecte a CE i CD. Els resultats instrumentals van corroborar la tendència dels resultats sensorials. Els valors mitjans per a to van disminuir en CD, P1, P2 i P3 i els seus valors mitjans de duresa, cohesividad i masticabilidad van augmentar. Es va observar en P3 la major percepció dels atributs sensorials duresa, intensitat del color groc i astringència. Durant el temps d'emmagatzemament, totes les mostres van disminuir els seus valors mitjans de lluminositat, croma i cohesividad i P1, P2 i P3 també van augmentar els seus valors mitjans d'elasticitat, [ EN ] Numerous studies have supported that a diet high in protein may promote weight loss and prevent its subsequent gain. Therefore, reformulation with the incorporation of these ingredients with satiating properties has been boosted. Reformulation of tartas de queso(CE), reducing milk fat content 50% (CD) and incorporating whey protein isolate at three different concentrations (P1 = 2%, 3% and P2 = P3 = 4%), the color, texture and sensory properties of the final product and its stability over time for 14 days of storage under refrigeration has been evaluated. Instrumental methods were used for determining the color (CIEL * a * b *parameters) and texture (double-cycle compression TPA) and flash profiling method for sensory evaluation of the samples. P3 showed the biggest differences in instrumental color and texture compared with Pc and the higher differences in the sensory evaluation with respect to Pe and Pc. The tendency of sensory results was corroborated with instrumentals results. Mean values were lower in pitch Pc, P1, P2 and P3 and their average values of hardness, cohesiveness and chewiness increased. P3 was evident in the increased appreciation of the sensory attributes hardness, intensity of the yellow color and astringency. During the time of storage, all samples decreased their brightness values, chroma and cohesiveness and P1, P2 and P3 also increased elasticity values.

Protein is the most satiating macronutrient and there is an effect of dietary protein source, with dairy whey protein being particularly effective in promoting satiety in adult humans. The underlying cause for this remains to be elucidated. The objectives were to confirm that whey protein is more satiating than maltodextrin carbohydrate in adult humans, to understand the potential mediating factors and to investigate which characteristic of whey protein gives rise to its satiating effect. Ad libitum food intake at a subsequent test meal after administration of a preload, subjective feelings of appetite (using visual analogue scales) and plasma concentrations of satiety-related hormones and metabolites were determined. Preload diets enriched with whey protein induced a greater reduction in subsequent food intake and suppression in rated feelings of appetite compared with maltodextrin carbohydrate (p<0.05). The time of consumption of the whey protein preload did not influence the satiety response. Plasma concentrations of pancreatic polypeptide hormone, total amino acids, and the branched-chain amino acids appear to play an important role in mediating the satiating effect of whey protein (sustained increases from 15 to 120 min following preload consumption, p<0.05). To determine the underlying characteristic of whey protein causing the satiating effect, the effects on satiety of whey protein components (glycomacropeptide, alpha-lactalbumin, or beta-lactoglobulin) and a free amino acid mixture simulating the amino acid composition of the whey protein were compared with that of the intact whey protein. The amino acid composition of whey protein per se appears to be important in the regulation of food intake and the induction of satiety. The individual constituent proteins or whey protein itself did not promote higher satiety than that found based on providing the free amino acids. The absorbed amino acid profile would appear to play an important role in mediating the sa

Kajmak is a Serbian autochthonous dairy product which is usually manufactured by the traditional production procedure. Kajmak is characterized by specific composition and unique properties and can be classified into the group of delicious dairy products, which takes place between cheese and butter. However, significant differences in the production conditions often result in a very large variations of the kajmak composition and quality, which prevent its widespread and organized appearance on the market. The process of kajmak formation can be divided into hot and cold phases. In the hot phase, due to the surface activity of proteins and fats, as well as the intense water evaporation, the formation of the initial skin layer occurs, which represents the base and the top layer of the final product (kajmak). In the cold phase, initial skin is being enriched by milk fat, resulting in the formation of the lower layer of the kajmak. Heat treatment of milk, which is present in the kajmak production, results in the significant changes in milk protein complex, such as the denaturation of whey proteins, formation of milk protein coaggregates as well as reaction of denatured whey proteins and milk fat globule membrane (MFGM). Due to the strong surface activity, milk fat globule and proteins diffuse to the top layer of milk and concentrate at the air-milk interface. Casein, due to its micellar form, has minor affinity for hydrophobic surfaces compared with individual components of casein micelles or casein preparations. Native whey proteins are globular and hence shows a little surface activity. However, milk heat treatment at temperatures between 70°C to 75°C cause denaturation of whey proteins as well as modification of their secondary and tertiary structure. These modifications cause changes in their functional properties, which result in the increasing of surface activity, altered interfacial rheology, emulsion and foaming properties and others. Environmental conditions repr, Kajmak je srpski autohtoni mlečni proizvod koji se prevashodno izraĎuje u domaćoj radinosti. Odlikuje se specifičnim sastavom i senzornim svojstvima, na osnovu kojih se može svrstati u grupu delikatesnih mlečnih proizvoda, koji se nalaze izmeĎu sireva i maslaca. MeĎutim, izrazita raznolikost uslova u kojima se proizvodi rezultira u izrazito velikom variranju sastava i kvaliteta kajmaka, koja onemogućavaju njegov organizovan i širi nastup na tržištu. Proces formiranja kajmaka može se podeliti na toplu i hladnu fazu. U toploj fazi, usled površinske aktivnosti masti i proteina, kao i intenzivnog isparavanja vode, dolazi do formiranja početne pokožice, koja predstavlja osnovu i gornji sloj kajmaka, dok u hladnoj fazi dolazi do obogaćivanja pokožice mlečnom mašću, pri čemu se formira donji sloj kajmaka. Termički tretman mleka zastupljen u proizvodnji kajmaka rezultuje izraženim promenama na proteinskom kompleksu mleka, pri čemu dolazi do denaturacije proteina surutke, stvaranja koagregata proteina mleka kao i reakcije denaturisanih proteina surutke sa proteinima iz adsorpcionog sloja globula mlečne masti (MFGM). Usled površinske aktivnosti masti i proteina vrelog mleka dolazi do njihove difuzije i koncentrisanja u graničnom sloju mleko-vazduh. Kazeini se u mleku nalaze u micelarnoj formi i kao takvi pokazuju mali afinitet prema hidrofobnim površinama. Nativni proteini surutke su globularni i sporije se adsorbuju. MeĎutim, nakon termičkog tretmana, na temperaturama od 70 do 75°C, proteini surutke denaturišu, pri čemu dolazi do modifikacije sekunadarne i tercijarne konformacije molekula ovih proteina. Ove modifikacije uzrokuju promene njihovih funkcionalnih svojstava, koje se ogledaju u povećanoj površinskoj aktivnosti, izmenjenoj meĎupovršinskoj reologiji, emulzionim i penivim svojstvima i dr. Ambijentalni uslovi u kojima se izvodi proces formiranja kajmaka predstavljaju značajan faktor u proizvodnji kajmaka. U toku procesa formiranja pokožice i kajmaka mleko se neprekidn

Kajmak je srpski autohtoni mlečni proizvod koji se prevashodno izraĎuje u domaćoj radinosti. Odlikuje se specifičnim sastavom i senzornim svojstvima, na osnovu kojih se može svrstati u grupu delikatesnih mlečnih proizvoda, koji se nalaze izmeĎu sireva i maslaca. MeĎutim, izrazita raznolikost uslova u kojima se proizvodi rezultira u izrazito velikom variranju sastava i kvaliteta kajmaka, koja onemogućavaju njegov organizovan i širi nastup na tržištu. Proces formiranja kajmaka može se podeliti na toplu i hladnu fazu. U toploj fazi, usled površinske aktivnosti masti i proteina, kao i intenzivnog isparavanja vode, dolazi do formiranja početne pokožice, koja predstavlja osnovu i gornji sloj kajmaka, dok u hladnoj fazi dolazi do obogaćivanja pokožice mlečnom mašću, pri čemu se formira donji sloj kajmaka. Termički tretman mleka zastupljen u proizvodnji kajmaka rezultuje izraženim promenama na proteinskom kompleksu mleka, pri čemu dolazi do denaturacije proteina surutke, stvaranja koagregata proteina mleka kao i reakcije denaturisanih proteina surutke sa proteinima iz adsorpcionog sloja globula mlečne masti (MFGM). Usled površinske aktivnosti masti i proteina vrelog mleka dolazi do njihove difuzije i koncentrisanja u graničnom sloju mleko-vazduh. Kazeini se u mleku nalaze u micelarnoj formi i kao takvi pokazuju mali afinitet prema hidrofobnim površinama. Nativni proteini surutke su globularni i sporije se adsorbuju. MeĎutim, nakon termičkog tretmana, na temperaturama od 70 do 75°C, proteini surutke denaturišu, pri čemu dolazi do modifikacije sekunadarne i tercijarne konformacije molekula ovih proteina. Ove modifikacije uzrokuju promene njihovih funkcionalnih svojstava, koje se ogledaju u povećanoj površinskoj aktivnosti, izmenjenoj meĎupovršinskoj reologiji, emulzionim i penivim svojstvima i dr. Ambijentalni uslovi u kojima se izvodi proces formiranja kajmaka predstavljaju značajan faktor u proizvodnji kajmaka. U toku procesa formiranja pokožice i kajmaka mleko se neprekidn, Kajmak is a Serbian autochthonous dairy product which is usually manufactured by the traditional production procedure. Kajmak is characterized by specific composition and unique properties and can be classified into the group of delicious dairy products, which takes place between cheese and butter. However, significant differences in the production conditions often result in a very large variations of the kajmak composition and quality, which prevent its widespread and organized appearance on the market. The process of kajmak formation can be divided into hot and cold phases. In the hot phase, due to the surface activity of proteins and fats, as well as the intense water evaporation, the formation of the initial skin layer occurs, which represents the base and the top layer of the final product (kajmak). In the cold phase, initial skin is being enriched by milk fat, resulting in the formation of the lower layer of the kajmak. Heat treatment of milk, which is present in the kajmak production, results in the significant changes in milk protein complex, such as the denaturation of whey proteins, formation of milk protein coaggregates as well as reaction of denatured whey proteins and milk fat globule membrane (MFGM). Due to the strong surface activity, milk fat globule and proteins diffuse to the top layer of milk and concentrate at the air-milk interface. Casein, due to its micellar form, has minor affinity for hydrophobic surfaces compared with individual components of casein micelles or casein preparations. Native whey proteins are globular and hence shows a little surface activity. However, milk heat treatment at temperatures between 70°C to 75°C cause denaturation of whey proteins as well as modification of their secondary and tertiary structure. These modifications cause changes in their functional properties, which result in the increasing of surface activity, altered interfacial rheology, emulsion and foaming properties and others. Environmental conditions repr

Whey protein isolate is used as a functional ingredient in acidic whey protein beverages, but the associated astringency is a big hurdle to introduce these beverages into the mainstream market. If we can solve the astringency issue, Fonterra would have big advantages over their competitors. Our hypothesis is that whey protein interacts with human saliva proteins and the subsequent precipitation causes astringency. In the present study, ion exchange whey protein isolates (WPI) 8855, and solutions of pure a-lac and ß-lg were used to determine which whey protein fractions are responsible for sedimentation in artificial or human saliva. It has been shown that sedimentation correlates to the level of astringency. Therefore only the level of sedimentation was investigated. The human saliva and artificial saliva were also compared in the astringency titration model in order to determine whether artificial saliva is representative of human saliva. Heat treatment (85°C, 30s) of whey protein solution was performed to mimic commercial beverage manufacture. The heated and non-heated whey protein solutions were titrated with artificial saliva, human saliva or sodium bicarbonate buffer in the range of pH 3 to 6. The sediment was recovered by centrifugation of the titrated samples, and analysed using liquid chromatography-mass spectrometry (LC-MS/MS) or one and two dimensional polyacrylamide gel electrophoresis (PAGE) with amido black and periodic acid Schiff stain. This study showed that ß-lg is the key sedimentation component in heated acidic WPI8855 beverages due to the heat aggregation, pH change through the isoelectric point and interaction with human saliva proteins, including mucin, proline-rich proteins (PRPS) and a-amylase. BSA also interacted with artificial and human saliva, whereas a-lac did not interact with either artificial or human saliva. Heat treatment caused extensive whey protein aggregation and precipitation. Artificial saliva and human saliva behaved differen

Las proteínas del suero proveniente del proceso de elaboración de quesos poseen propiedades funcionales específicas y un elevado valor nutricional. Por esta razón, estas proteínas son utilizadas en la elaboración de sistemas alimentarios. El proceso de congelación (congelación, almacenamiento del producto congelado y descongelación) es un tratamiento ampliamente utilizado para conservar ingredientes y alimentos elaborados. No obstante, la formación de cristales de hielo puede afectar la calidad de estos productos. El objetivo general de esta tesis fue estudiar el efecto del proceso de congelación sobre las características físicas y químicas de sistemas alimentarios (suspensiones y un queso blando magro) elaborados con proteínas del suero. Se estudiaron suspensiones de proteínas del suero que fueron tratadas térmicamente a cuatro temperaturas y sometidas al proceso de congelación. Se analizó el contenido de proteína que se desnaturalizó y/o que formó agregados (PDA) y se determinó la cinética global de desnatualización-agregación. Además, se estudiaron quesos blandos magros elaborados con proteínas del suero que fueron sometidos al proceso de congelación, tomando muestras a distintos tiempos de maduración. Se determinaron las propiedades fisicoquímicas (humedad, concentración de sal, pH, proteína total y proteína en la fracción soluble a pH 4,6) y se calcularon los índices de maduración. Las propiedades reológicas de las suspensiones y de los quesos estudiados fueron analizadas por medio de ensayos oscilatorios realizando barridos de frecuencia dentro de la región de viscoelasticidad lineal. Los resultados obtenidos permitieron caracterizar a los sistemas alimentarios estudiados, identificando las propiedades que fueron afectadas por el proceso de congelación., Whey proteins have specific functional properties and high nutritional value. For this reason, they can be used to elaborate food systems. Freezing process (freezing, storage of the frozen product, and thawing) is a conservation technique widely used to preserve ingredients and processed foods. However, the formation of ice crystals can affect the quality of these products. The main objective of this thesis was to study the effect of the freezing process on the physical and chemical properties of food systems (suspensions and low-fat Soft Cheeses) elaborated with whey proteins. Suspensions of whey proteins were heat treated at four temperatures and frozen. The denatured/aggregated protein content was analyzed and the overall kinetic of denaturation-aggregation was determined. Low-fat Soft cheeses elaborated with whey proteins were frozen and analyzed at different ripening times. Physicochemical properties like moisture content, salt concentration, pH, total protein content, protein content in the soluble fraction at pH 4.6, and index of maturation were determined. Rheological properties of suspensions and cheeses were analyzed performing frequency sweeps in the linear viscoelastic region. Based on the results, the characterization of the analyzed food systems could be conducted, identifying the properties that have been affected by freezing process., Consejo Nacional de Investigaciones Cietíficas y Técnicas, Agencia Nacional de Promoción Científica y Tecnológica, Unversidad Nacional del Litoral

High nutritional value expressed with well balanced essential amino acid ratio, as well as favorable physic-chemical properties, make whey proteins very interesting ingredients for food industry and other industry branches. Whey proteins are mostly used for the improvement of nutritive value of the final product, as well as for the attaining certain technological-functional properties of product, such as foam or gel forming and emulsion forming and stabilization. Wide palette of products based on whey proteins is well know and whey protein concentrates, isolates and hydrolysates have the widest appliance. However, in recent world literature, more and more data show significant therapeutic effect of some less represented whey proteins, even in a medical treatment of the most serious illnesses. Refined whey proteins have defensive role in organism and therapeutic function, which opens possibility of refined whey protein industry development., Visoka nutritivna vrednost izražena dobro izbalansiranim odnosom esencijalnih aminokiselina, kao i povoljne fizičko-hemijske osobine čine serum proteine vrlo interesantnim ingredijentima u prehrambenoj i drugim granama industrije. Serum proteini se najčešće koriste u cilju poboljšanja hranljive vrednosti finalnog proizvoda, kao i radi postizanja određenih tehnološko-funkcionalnih svojstava proizvoda, poput obrazovanja pene ili gela, obrazovanja i stabilizacije emulzije. Danas je poznata široka paleta proizvoda na bazi serum proteina, pri čemu su proteinski koncentrati, izolati i hidrolizati našli najširu primenu. Međutim, u savremenoj svetskoj literaturi sve je više podataka o značajnom terapeutskom efektu pojedinih manje zastupljenih serum proteina čak i pri lečenju i najtežih oboljenja, što otvara mogućnost razvoja industrije prečišćenih proteina surutke, koji imaju odbrambenu ulogu u organizmu i terapeutsku funkciju.

This paper deals with the investigation of the impact of the heat treatment of reconstituted skim milk conducted at different temperatures, and the adding of demineralized whey on the protein solubility, soluble protein composition and interactions involved between proteins in a chemical complex. Commercial skim milk has been reconstituted and heat treated at 75 degrees C, 85 degrees C and 90 degrees C for 20 minutes. Demineralized whey has been added in concentrations of 0.5%, 1.0 and 2.0%. The soluble protein composition has been determined by the polyacrilamide gel electrophoresis (SDS-PAGE) and by the densitometric analysis. Due to the different changes occurred during treatments at different temperatures, proteins of heat-treated samples containing added demineralized whey have had significantly different solubility. At lower temperatures (75 degrees C and 85 degrees C) the adding of demineralized whey decreased the protein solubility by 5.28%-26.41%, while the addition of demineralized whey performed at 90 degrees C increased the soluble protein content by 5.61%-28.89%. Heat treatments, as well as the addition of demineralized whey, have induced high molecular weight complex formation. beta-Lg, alpha-La and kappa-casein are involved in high molecular weight complexes. The disulfide interactions between denatured molecules of these proteins are mostly responsible for the formation of coaggregates. The level of their interactions and the soluble protein composition are determined by the degree of temperature.

In recent years, partly due to advances in protein separation technology, many studies have focused on the immunomodulatory activity of bovine milk and colostral protein components. Individual milk proteins have been purified for the purpose of studying their physical properties and physiological functions. Today there is substantial evidence to indicate that the major components of bovine milk, such as whey protein and several highly purified whey protein isolates, can regulate immune function in heterologous species. Intense research has focused on identifying biologically active components within bovine milk whey, as well as characterising the mode by which mammalian immune function is modulated by these components. However, information regarding the effect of bovine whey proteins on immune responses to orally and parentally-administered antigens is currently conflicting and far from exhaustive. Consequently, this thesis sought not only to investigate the immunomodulatory ability of previously untested bovine whey products on general immunoresponses but also to investigate the ability of bovine whey proteins to modulate murine immune responses to vaccines currently in routine medical use. Initially, individual whey proteins (α-lactalbumin, β-lactoglobulin and lactoferrin) were screened for their in vitro effects on lymphoid cell function and phagocytic function. These in vitro studies found that the individual whey protein components had a positive immunomodulatory effect, providing evidence that these components have the potential to enhance immune function, and investigation into their immunomodulatory capabilities in an in vivo murine model was consequently undertaken. The results of the in vivo studies demonstrated that the dietary whey protein isolates and whey protein concentrate tested in this study could not only enhance two important indices of ex vivo lymphoid and non-lymphoid cell function (lymphocyte proliferation and phagocytic function) but could en

Two variants of fresh cheese were prepared: cheese prepared from milk heated at 650C for 30 minutes (control samples) and those prepared from milk heated for 10 minutes at 850C (experimental samples). Second method caused the protein co aggregates formation. Results of these investigations suggested that the whey obtained during fresh cheese production from co aggregates had considerable lower total nitrogen content (0.0601%) and milk fat content (0.08%). These values represented 46.37% and 33.33% of the control samples respectively. Also, dry matter of experimental whey samples was lower for 3.72% than in the whey of control samples. The cheese prepared on the basis of co aggregates had for 5.11% lower total solids content than control samples. The average values of these and control samples were 28.38% and 33.49% respectively. This may be due to protein co aggregates properties and the different structure of cheese curd. Disregarding to the higher utilization of the milk fat, the lower milk fat content in total solids content of experimental cheese is the result of higher participation of total nitrogen., Sveži sir je izrađen u dve varijante: a) od mleka termički tretiranog na 650C u toku 30 minuta (kontrolni sir) i b) od mleka termički tretiranog na 870C u toku 10 minuta (ogledni sir), u kom su obrazovani koagregati proteina mleka (hemijski kompleks između kazeina i serum proteina). Rezultati istraživanja su pokazali da je surutka dobijena proizvodnjom svežeg sira na bazi koagregata proteina mleka imala znatno manji sadržaj ukupnog azota (0.0601%), što čini 46.37% ukupnih azotnih materija surutke kontrolnih sireva. Znatno manji sadržaj mlečne masti (0.08%) čini 33.33% mlečne masti surutke kontrolnih sireva. Takođe, ukupan sadržaj suve materije iznosio je 6.21%, što je za 3.72% manje u odnosu na suvu materiju surutke kontrolnih sireva. Ogledni sirevi imali su 5.11% manji sadržaj suve materije nego kontrolni sirevi. Kod oglednih sireva sadržaj suve materije u proseku je iznosio 28.38%, a kod kontrolnih 33.49%. Teže izdvajanje vode kod oglednih sireva može se objasniti prirodom koagregata proteina mleka i postojanjem drugačije strukture sirnog testa oglednih sireva. Manji sadržaj mlečne masti u suvoj materiji oglednih sireva posledica je većeg učešća ukupnog azota u suvoj materiji sira, bez obzira na veće iskorišćenje mlečne masti.