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M L Gigante - One of the best experts on this subject based on the ideXlab platform.
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Effect of addition of CO2 to raw milk on quality of UHT-treated milk.
Journal of Dairy Science, 2012Co-Authors: P C B Vianna, M E F Dias, F M Netto, Eduardo H.m. Walter, J A F Faria, M L GiganteAbstract:The objective of this study was to evaluate the effect of addition of CO2 to raw milk on UHT milk quality during storage. Control milk (without CO2 addition) and treated milk (with CO2 addition up to pH 6.2) were stored in bulk tanks at 4 degrees C for 6 d. After storage, both samples were UHT processed using indirect heating (140 degrees C for 5 s). Samples were aseptically packed in low-density polyethylene pouches and stored in the dark at room temperature. Raw milk was evaluated upon receipt for physicochemical composition, Proteolysis, lipolysis, standard plate count, psychrotrophic bacteria, and Pseudomonas spp. counts, and after 6 d of storage for Proteolysis, lipolysis, and microbial counts. After processing, UHT milk samples were evaluated for physicochemical composition, Proteolysis, and lipolysis. Samples were evaluated for Proteolysis and lipolysis twice a month until 120 d. Peptides from pH 4.6-soluble N filtrates were performed by reversed-phase HPLC after 1 and 120 d of storage. A split-plot design was used and the complete experiment was carried out in triplicate. The results were evaluated by ANOVA and Tukey's test. After 6 d of storage, CO2-treated raw milk kept its physicochemical and microbiological quality, whereas the untreated milk showed significant quality losses. A significant increase in Proteolysis occurred during 120 d of storage in both treatments, but the increase occurred 1.4 times faster in untreated UHT milk than in CO2-treated UHT milk. In both UHT milks, the Proteolysis was a consequence of the action of plasmin and microbial proteases. However, the untreated UHT milk showed higher microbial protease activity than the treated UHT milk. The addition of CO2 to the raw milk maintained the quality during storage, resulting in UHT milk with less Proteolysis and possibly longer shelf life, which is usually limited by age gelation of UHT milk.
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Effect of addition of CO₂ to raw milk on quality of UHT-treated milk.
Journal of dairy science, 2012Co-Authors: P C B Vianna, M E F Dias, F M Netto, Eduardo H.m. Walter, J A F Faria, M L GiganteAbstract:The objective of this study was to evaluate the effect of addition of CO(2) to raw milk on UHT milk quality during storage. Control milk (without CO(2) addition) and treated milk (with CO(2) addition up to pH 6.2) were stored in bulk tanks at 4°C for 6d. After storage, both samples were UHT processed using indirect heating (140°C for 5s). Samples were aseptically packed in low-density polyethylene pouches and stored in the dark at room temperature. Raw milk was evaluated upon receipt for physicochemical composition, Proteolysis, lipolysis, standard plate count, psychrotrophic bacteria, and Pseudomonas spp. counts, and after 6d of storage for Proteolysis, lipolysis, and microbial counts. After processing, UHT milk samples were evaluated for physicochemical composition, Proteolysis, and lipolysis. Samples were evaluated for Proteolysis and lipolysis twice a month until 120d. Peptides from pH 4.6-soluble N filtrates were performed by reversed-phase HPLC after 1 and 120d of storage. A split-plot design was used and the complete experiment was carried out in triplicate. The results were evaluated by ANOVA and Tukey's test. After 6d of storage, CO(2)-treated raw milk kept its physicochemical and microbiological quality, whereas the untreated milk showed significant quality losses. A significant increase in Proteolysis occurred during 120d of storage in both treatments, but the increase occurred 1.4 times faster in untreated UHT milk than in CO(2)-treated UHT milk. In both UHT milks, the Proteolysis was a consequence of the action of plasmin and microbial proteases. However, the untreated UHT milk showed higher microbial protease activity than the treated UHT milk. The addition of CO(2) to the raw milk maintained the quality during storage, resulting in UHT milk with less Proteolysis and possibly longer shelf life, which is usually limited by age gelation of UHT milk.
Paul L.h. Mcsweeney - One of the best experts on this subject based on the ideXlab platform.
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Rennet activity and Proteolysis in reggianito Argentine hard cooked cheese
Australian Journal of Dairy Technology, 2020Co-Authors: Erica R. Hynes, M. C. Candioti, C. A. Zalazar, Paul L.h. McsweeneyAbstract:It is generally believed that enzymes in rennet are largely denatured by cooking during the manufacture of hard cheese. However, typical products of rennet action on α s1 -casein have been detected in these varieties. The aim of the present work was to relate residual rennet activity with Proteolysis in Reggianito Argentino, a hard cooked cheese. For that purpose, we analysed samples of cheese cooked at low (45°C), control (52°C) or high temperature (60°C) for residual rennet activity. We also studied Proteolysis in cheese at the end of ripening by means of peptide mapping and electrophoresis. Rennet activity was inversely proportional to cooking temperature, although the activity was quantifiable even in cheeses cooked at high temperature, suggesting renaturation or incomplete denaturation of the enzyme. Indices of Proteolysis, especially the levels of the peptide α s1 -CN(f24-199), were consistent with residual rennet activity. Secondary Proteolysis was also different for cheeses cooked at different temperatures.
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Proteolysis in caprine milk cheese treated by high pressure to accelerate cheese ripening
International Dairy Journal, 2002Co-Authors: Jordi Saldo, A. L. Kelly, Esther Sendra, Paul L.h. Mcsweeney, Buenaventura GuamisAbstract:The application of high-pressure treatment to a hard caprine milk cheese was studied as a method of acceleration of Proteolysis during ripening. Levels of Proteolysis in the cheese subjected to treatment at 50 MPa for 72 h were only slightly different to those in control cheese, with differences being less apparent by the end of ripening. Treatment at 400 MPa for 5 min caused more significant quantitative and qualitative changes in Proteolysis that persisted throughout the ripening. This treatment resulted in increased levels of free amino acids, although cheese treated at 400 MPa had profiles of peptides and caseins, obtained by HPLC and PAGE, similar to younger untreated cheese or cheese treated at 50 MPa. Plasmin activity in cheese was unaffected by pressure treatment, whereas coagulant activity was decreased by treatment at 400 MPa. Overall, application of high pressure at the beginning of ripening significantly increased secondary Proteolysis, or conversion of peptides into free amino acids. © 2002 Elsevier Science Ltd. All rights reserved.
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advances in the study of Proteolysis during cheese ripening
International Dairy Journal, 2001Co-Authors: M. J. Sousa, Ylva Ardö, Paul L.h. McsweeneyAbstract:Cheese ripening involves a complex series of biochemical, and probably some chemical events, that leads to the characteristic taste, aroma and texture of each cheese variety. The most complex of these biochemical events, Proteolysis, is caused by agents from a number of sources: residual coagulant (usually chymosin), indigenous milk enzymes, starter, adventitious non-starter microflora and, in many varieties, enzymes from secondary flora (e.g., from Penicillium sp. in mould-ripened cheeses or Propionibacterium sp. in Swiss cheese). Proteolysis in cheese has been the subject of active research in the last decade; there have been developments in the analytical techniques used to monitor Proteolysis and patterns of Proteolysis in many cheese varieties have now been investigated. This review focuses on certain aspects of Proteolysis, including proteolytic agents in cheese and specificity of some ripening enzymes, comparison of Proteolysis and contribution of Proteolysis to cheese flavour.
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Advances in the study of Proteolysis during cheese ripening
International Dairy Journal, 2001Co-Authors: M. J. Sousa, Ylva Ardö, Paul L.h. McsweeneyAbstract:Cheese ripening involves a complex series of biochemical, and probably some chemical events, that leads to the characteristic taste, aroma and texture of each cheese variety. The most complex of these biochemical events, Proteolysis, is caused by agents from a number of sources: residual coagulant (usually chymosin), indigenous milk enzymes, starter, adventitious non-starter microflora and, in many varieties, enzymes from secondary flora (e.g., from Penicillium sp. in mould-ripened cheeses or Propionibacterium sp. in Swiss cheese). Proteolysis in cheese has been the subject of active research in the last decade; there have been developments in the analytical techniques used to monitor Proteolysis and patterns of Proteolysis in many cheese varieties have now been investigated. This review focuses on certain aspects of Proteolysis, including proteolytic agents in cheese and specificity of some ripening enzymes, comparison of Proteolysis and contribution of Proteolysis to cheese flavour. © 2001 Elsevier Science Ltd. All rights reserved.
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Methods for Assessing Proteolysis in Cheese During Maturation
Advances in Experimental Medicine and Biology, 1995Co-Authors: Paul L.h. Mcsweeney, T. K. SinghAbstract:Proteolysis is the principal and most complex biochemical event occurring during the maturation of the majority of ripened cheese varieties. The extent of Proteolysis varies from very limited (e.g., Mozzarella) to very extensive (e.g., blue-mould varieties). The products of Proteolysis vary from large polypeptides, comparable in size with intact caseins, through a range of intermediate-sized and small peptides to free amino acids and their degradation products. Proteolysis in cheese involves a complex and dynamic series of events and has important implications for the development of the correct flavour and texture characteristic of the variety. Owing to its complexity and importance to the biochemistry of cheese ripening, Proteolysis in cheese has been the subject of much study and a wide range of analytical techniques have been developed to assess its extent and nature.
C. A. Zalazar - One of the best experts on this subject based on the ideXlab platform.
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Rennet activity and Proteolysis in reggianito Argentine hard cooked cheese
Australian Journal of Dairy Technology, 2020Co-Authors: Erica R. Hynes, M. C. Candioti, C. A. Zalazar, Paul L.h. McsweeneyAbstract:It is generally believed that enzymes in rennet are largely denatured by cooking during the manufacture of hard cheese. However, typical products of rennet action on α s1 -casein have been detected in these varieties. The aim of the present work was to relate residual rennet activity with Proteolysis in Reggianito Argentino, a hard cooked cheese. For that purpose, we analysed samples of cheese cooked at low (45°C), control (52°C) or high temperature (60°C) for residual rennet activity. We also studied Proteolysis in cheese at the end of ripening by means of peptide mapping and electrophoresis. Rennet activity was inversely proportional to cooking temperature, although the activity was quantifiable even in cheeses cooked at high temperature, suggesting renaturation or incomplete denaturation of the enzyme. Indices of Proteolysis, especially the levels of the peptide α s1 -CN(f24-199), were consistent with residual rennet activity. Secondary Proteolysis was also different for cheeses cooked at different temperatures.
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proteolytic activity of three probiotic strains in semi hard cheese as single and mixed cultures lactobacillus acidophilus lactobacillus paracasei and bifidobacterium lactis
International Dairy Journal, 2009Co-Authors: Carina Viviana Bergamini, E R Hynes, S Palma, Nora Sabbag, C. A. ZalazarAbstract:Abstract The influence of three probiotic strains ( Lactobacillus acidophilus , Lactobacillus paracasei and Bifidobacterium lactis ) in semi-hard cheese Proteolysis patterns was assessed. Probiotics were inoculated both as single cultures and as a three-strain mix, and added to milk either after a pre-incubation step or directly to the vat. B. lactis did not show any effect on Proteolysis of cheeses, while L. paracasei showed limited impact at the end of the ripening. In contrast, L. acidophilus significantly influenced secondary Proteolysis from the beginning of ripening, causing an increase in the levels of small nitrogen-containing compounds and free amino acids and changes in the peptide profiles. The effect of Lactobacillus acidophilus on peptidolysis was more noticeable when it was added to cheese–milk after pre-incubation in an enriched milk fat substrate. Similar results obtained with the three-strain mixed culture, suggesting that L. acidophilus played a major role in secondary Proteolysis of probiotic cheeses in this trial.
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influence of probiotic bacteria on the Proteolysis profile of a semi hard cheese
International Dairy Journal, 2006Co-Authors: Carina Viviana Bergamini, Erica R. Hynes, C. A. ZalazarAbstract:Abstract Two probiotic strains, Lactobacillus acidophilus and Lactobacillus paracasei subsp. paracasei, were used as adjunct cultures in semi-hard cheesemaking experiments, in order to study their influence on Proteolysis during ripening. Cheeses with and without probiotic bacteria were manufactured. The population of probiotics remained above 107 cfu g−1 during all ripening, and they did not influence primary Proteolysis. However, L. acidophilus produced a significant increase in the level of low molecular weight nitrogen compounds and individual free amino acids; the amino acid profiles were also different. Multivariate analysis of peptide profiles showed that samples were grouped mainly by ripening time, although the impact of probiotics was also noticeable. L. acidophilus showed a clear influence on secondary Proteolysis, while a minor effect of L. paracasei was evidenced at the end of the ripening. These results showed that the tested strains influenced distinctly Proteolysis of cheeses, probably as a consequence of their different proteolytic systems and their activity via the alimentary matrix (cheese).
P C B Vianna - One of the best experts on this subject based on the ideXlab platform.
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Effect of addition of CO2 to raw milk on quality of UHT-treated milk.
Journal of Dairy Science, 2012Co-Authors: P C B Vianna, M E F Dias, F M Netto, Eduardo H.m. Walter, J A F Faria, M L GiganteAbstract:The objective of this study was to evaluate the effect of addition of CO2 to raw milk on UHT milk quality during storage. Control milk (without CO2 addition) and treated milk (with CO2 addition up to pH 6.2) were stored in bulk tanks at 4 degrees C for 6 d. After storage, both samples were UHT processed using indirect heating (140 degrees C for 5 s). Samples were aseptically packed in low-density polyethylene pouches and stored in the dark at room temperature. Raw milk was evaluated upon receipt for physicochemical composition, Proteolysis, lipolysis, standard plate count, psychrotrophic bacteria, and Pseudomonas spp. counts, and after 6 d of storage for Proteolysis, lipolysis, and microbial counts. After processing, UHT milk samples were evaluated for physicochemical composition, Proteolysis, and lipolysis. Samples were evaluated for Proteolysis and lipolysis twice a month until 120 d. Peptides from pH 4.6-soluble N filtrates were performed by reversed-phase HPLC after 1 and 120 d of storage. A split-plot design was used and the complete experiment was carried out in triplicate. The results were evaluated by ANOVA and Tukey's test. After 6 d of storage, CO2-treated raw milk kept its physicochemical and microbiological quality, whereas the untreated milk showed significant quality losses. A significant increase in Proteolysis occurred during 120 d of storage in both treatments, but the increase occurred 1.4 times faster in untreated UHT milk than in CO2-treated UHT milk. In both UHT milks, the Proteolysis was a consequence of the action of plasmin and microbial proteases. However, the untreated UHT milk showed higher microbial protease activity than the treated UHT milk. The addition of CO2 to the raw milk maintained the quality during storage, resulting in UHT milk with less Proteolysis and possibly longer shelf life, which is usually limited by age gelation of UHT milk.
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Effect of addition of CO₂ to raw milk on quality of UHT-treated milk.
Journal of dairy science, 2012Co-Authors: P C B Vianna, M E F Dias, F M Netto, Eduardo H.m. Walter, J A F Faria, M L GiganteAbstract:The objective of this study was to evaluate the effect of addition of CO(2) to raw milk on UHT milk quality during storage. Control milk (without CO(2) addition) and treated milk (with CO(2) addition up to pH 6.2) were stored in bulk tanks at 4°C for 6d. After storage, both samples were UHT processed using indirect heating (140°C for 5s). Samples were aseptically packed in low-density polyethylene pouches and stored in the dark at room temperature. Raw milk was evaluated upon receipt for physicochemical composition, Proteolysis, lipolysis, standard plate count, psychrotrophic bacteria, and Pseudomonas spp. counts, and after 6d of storage for Proteolysis, lipolysis, and microbial counts. After processing, UHT milk samples were evaluated for physicochemical composition, Proteolysis, and lipolysis. Samples were evaluated for Proteolysis and lipolysis twice a month until 120d. Peptides from pH 4.6-soluble N filtrates were performed by reversed-phase HPLC after 1 and 120d of storage. A split-plot design was used and the complete experiment was carried out in triplicate. The results were evaluated by ANOVA and Tukey's test. After 6d of storage, CO(2)-treated raw milk kept its physicochemical and microbiological quality, whereas the untreated milk showed significant quality losses. A significant increase in Proteolysis occurred during 120d of storage in both treatments, but the increase occurred 1.4 times faster in untreated UHT milk than in CO(2)-treated UHT milk. In both UHT milks, the Proteolysis was a consequence of the action of plasmin and microbial proteases. However, the untreated UHT milk showed higher microbial protease activity than the treated UHT milk. The addition of CO(2) to the raw milk maintained the quality during storage, resulting in UHT milk with less Proteolysis and possibly longer shelf life, which is usually limited by age gelation of UHT milk.
M. J. Sousa - One of the best experts on this subject based on the ideXlab platform.
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advances in the study of Proteolysis during cheese ripening
International Dairy Journal, 2001Co-Authors: M. J. Sousa, Ylva Ardö, Paul L.h. McsweeneyAbstract:Cheese ripening involves a complex series of biochemical, and probably some chemical events, that leads to the characteristic taste, aroma and texture of each cheese variety. The most complex of these biochemical events, Proteolysis, is caused by agents from a number of sources: residual coagulant (usually chymosin), indigenous milk enzymes, starter, adventitious non-starter microflora and, in many varieties, enzymes from secondary flora (e.g., from Penicillium sp. in mould-ripened cheeses or Propionibacterium sp. in Swiss cheese). Proteolysis in cheese has been the subject of active research in the last decade; there have been developments in the analytical techniques used to monitor Proteolysis and patterns of Proteolysis in many cheese varieties have now been investigated. This review focuses on certain aspects of Proteolysis, including proteolytic agents in cheese and specificity of some ripening enzymes, comparison of Proteolysis and contribution of Proteolysis to cheese flavour.
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Advances in the study of Proteolysis during cheese ripening
International Dairy Journal, 2001Co-Authors: M. J. Sousa, Ylva Ardö, Paul L.h. McsweeneyAbstract:Cheese ripening involves a complex series of biochemical, and probably some chemical events, that leads to the characteristic taste, aroma and texture of each cheese variety. The most complex of these biochemical events, Proteolysis, is caused by agents from a number of sources: residual coagulant (usually chymosin), indigenous milk enzymes, starter, adventitious non-starter microflora and, in many varieties, enzymes from secondary flora (e.g., from Penicillium sp. in mould-ripened cheeses or Propionibacterium sp. in Swiss cheese). Proteolysis in cheese has been the subject of active research in the last decade; there have been developments in the analytical techniques used to monitor Proteolysis and patterns of Proteolysis in many cheese varieties have now been investigated. This review focuses on certain aspects of Proteolysis, including proteolytic agents in cheese and specificity of some ripening enzymes, comparison of Proteolysis and contribution of Proteolysis to cheese flavour. © 2001 Elsevier Science Ltd. All rights reserved.
