论文信息 - Enzymatic hydrolysis of milk proteins under alkaline and acidic conditions

Enzymatic hydrolysis of milk proteins under alkaline and acidic conditions

The pH-stat and osmometric methods were adopted for control of hydrolysis of casein and whey proteins by chymotrypsin, trypsin and pepsin. Experiments in alkaline medium showed that the mean pK values determined for amino groups in milk protein hydrolysates at 52°C were 7.11 for casein hydrolysates and 7.18 for whey protein hydrolysates. During hydrolysis in acidic medium the osmotic coefficients determined for casein and whey proteins enabled calculation of the calibration factor for the osmometer (1.05) which could be assumed as constant. Results will enable monitoring of DH during hydrolysis of milk proteins in such systems.

S. Ziajka | W. Dzwolak | W. Dzwolak | S. Ziajka

[1] C. Jacobsen,et al. The pH-stat and its use in biochemistry. , 1957, Methods of biochemical analysis.

[2] F. Richards. Titration of amino groups released during the digestion of ribonuclease by subtilisin. , 1955, Comptes rendus des travaux du Laboratoire Carlsberg. Serie chimique.

[3] S. Beychok,et al. Chapter 8 – Interaction of Proteins with Hydrogen Ions and Other Small Ions and Molecules , 1964 .

[4] P. Antila. In Vitro Digestion of Bovine Milk Proteins by Trypsin Hydrolysis and pH-Stat Analysis , 1989 .

[5] A. Renken,et al. Continuous Monitoring of Enzymatic Whey Protein Hydrolysis. Correlation of Base Consumption with Soluble Nitrogen Content , 1994 .

[6] J. Adler-Nissen. Determination of the degree of hydrolysis of food protein hydrolysates by trinitrobenzenesulfonic acid. , 1979, Journal of agricultural and food chemistry.