Hostname: page-component-8448b6f56d-dnltx Total loading time: 0 Render date: 2024-04-24T15:51:54.609Z Has data issue: false hasContentIssue false

Kinetic studies of in vivo digestion of bovine unheated skim-milk proteins in the rat stomach

Published online by Cambridge University Press:  01 June 2009

Guy Miranda
Affiliation:
Laboratoire de Biochimie et Technologie Laitières, Institut National de la Recherche Agronomique, CNRZ 78350, Jouy-en-Josas, France
Jean-Pierre Pelissier
Affiliation:
Laboratoire de Biochimie et Technologie Laitières, Institut National de la Recherche Agronomique, CNRZ 78350, Jouy-en-Josas, France

Summary

The in vivo action of gastric proteinases on bovine milk proteins was studied in rats fed with skim-milk, by analysing gastric contents after 30, 60 and 240 min of digestion. Gastric proteolysis was already marked after 30 min of digestion and liberated a large number of peptides with different molecular weights. αs1-Casein and β-casein were still the main components of the stomach contents together with α-lactalbumin and β-lactoglobulin, which were little degraded, even after 240 min of digestion. A statistical analysis (multivariate method), made on several parameters (such as pH, N, and NPN) showed changes in the stomach contents during the digestion. The amino acid composition of the protein fraction was close to that of the diet, whilst that of the non-protein fraction was very different, being between the amino acid composition of the endogenous proteins and that of the diet.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1983

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alais, C. 1963 [Study of the secretion of coagulating enzymes in the abomasum of the lamb.] Annales de Biologie Animale, Biochimie, Biaphysique 3 6570.CrossRefGoogle Scholar
Benzecri, J. P. 1972 [Analysis of data, vol. 2.] Tome II. Paris: Dunod.Google Scholar
Berridge, N. J., Davis, J. G., Kon, P. M., Kon, S. K. & Spratling, F. R. 1943 The production of rennet from living calves. Journal of Dairy Research 13 145161.CrossRefGoogle Scholar
Creamer, L. K., Mills, O. E. & Richards, E. L. 1971 The action of rennet on the caseins. I: Rennin action on β-casein-B in solution. Journal of Dairy Research 38 269280.CrossRefGoogle Scholar
Delfour, A., Alais, C. & Jolles, P. 1966 Structure of cow's κ-caseino-glycopeptide: the N terminal octapeptide. Chimia 20 148150.Google Scholar
Gripon, J. C., Desmazeaud, M. J., Le Bars, D. & Bergere, J. L. 1975 [Study on the role of microorganisms and enzymes during the maturation of cheeses. 2. Effect of commercial rennet.] Lait 55 502516.CrossRefGoogle Scholar
Hill, M. D. 1974 Correspondence analysis: a neglected multivariate method. Applied Statistics 23 340354.Google Scholar
Hill, R. D., Lahav, E. & Givol, D. 1974 A rennin-sensitive bond in αs1-B casein. Journal of Dairy Research 41 147153.Google Scholar
Lison, L. 1958 [Statistics applied to biology.] Paris: Gauthier, Villars.Google Scholar
Miranda, G. & Pelissier, J. -P. 1981 In vivo studies on the digestion of bovine caseins in the rat stomach. Journal of Dairy Research 48 319326.CrossRefGoogle Scholar
Mulvihill, D. M. & Fox, P. F. 1979 a Proteolytic specificity of chymosin on bovine αs1-casein. Journal of Dairy Research 46 641651CrossRefGoogle Scholar
Mulvihill, D. M. & Fox, P. F. 1979 b Proteolytic specificity of chymosins and pepsins on β-caseins. Milchwissenschafl 34 680683.Google Scholar
Pelissier, J. -P., Mercier, J. C. & Ribadeau-Dumas, B. 1974 [Study on the proteolysis of αs1- and β-caseins by rennet. Specificity of action. Bitter peptides released.] Annales de Biologie Animale, Biochimie, Biophysique 14 343362.CrossRefGoogle Scholar
Trieu-Cuot, P. & Gripon, J. C. 1981 Electrofocusing and two dimensional electrophoresis of bovine caseins. Journal of Dairy Research 48 303310.CrossRefGoogle Scholar
Uriel, J. 1966 [Method of electrophoresis in acrylamide-agarose gels.] Bulletin de la Société de Chimie Biologie 48 969982.Google Scholar
Visser, S. & Slangen, K. J. 1977 On the specificity of chymosin (rennin) in its action on bovine β-casein B. Netherlands Milk and Dairy Journal 31 1630Google Scholar