Caseins peptic hydrolysis

Peptic hydrolysis of ester derivatives of /3-casein and a-lactalbumin... 

Sitohy, M., Chobert, J.-M., and Haertle, T. 2001b. Peptic hydrolysis of methyl-, ethyl- and propyl-ester derivatives of (3-casein and a-lactalbumin. Milchwissenschaft 56, 303-307. 

Enzymatic gelation of partially heat-denatured whey proteins by trypsin, papain, pronase, pepsin, and a preparation of Streptomyces griseus has been studied (Sato et al., 1995). Only peptic hydrolysate did not form a gel. The strength of the gel depended on the enzyme used and increased with increasing DH. Hydrolysis of whey protein concentrate with a glutamic acid specific protease from Bacillus licheniformis at pH 8 and 8% protein concentration has been shown to produce plastein aggregates (Budtz and Nielsen, 1992). The viscosity of the solution increased dramatically during hydrolysis and reached a maximum at 6% DH. Incubation of sodium caseinate with pepsin or papain resulted in a 55-77% reduction in the apparent viscosity (Hooker et al., 1982). 

To summarize, the final products of peptic digestion are composed of deutero-albumose C, products not precipitable by phosphotungstic acid, and peptones. The different results which have just been set forth relate to serum-albumin. Zunz has found that egg-albumin, casein or globulin, treated in a similar way, act in a similar manner. Yet the progress of digestion of these various materials does not show entirely the same course. In general, extensive hydrolysis is reached with these bodies with more difficulty than with serum-albumin. 

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