Determination of the proportion of κ-casein hydrolysed by rennet on coagulation of skim-milk
- 1 October 1980
- journal article
- research article
- Published by Cambridge University Press (CUP) in Journal of Dairy Research
- Vol. 47 (3), 351-358
- https://doi.org/10.1017/s0022029900021245
Abstract
Summary: A method has been developed for quantitative determination of para-κ-casein, involving spectrophotometric scanning of stained protein bands following polyacrylamide gel electrophoresis. The rate of hydrolysis of κ-casein in skim-milk at pH 6·6 and 30 °C was compared with that in EDTA-treated skim-milk under the same conditions. This showed that at the visually observed clotting time, at least 90% of the total κ-casein in milk had been hydrolysed. The time course of the reaction was consistent with all the κ-casein molecules being hydrolysed with the same efficiency. The results strongly suggest that essentially all of the κ-casein in milk is equally accessible to rennet action. This is consistent with the casein micelle being porous, or having all the κ-casein on the surface.This publication has 32 references indexed in Scilit:
- Intermicellar relationships in rennet-treated separated milk: II. Process of gel assemblyJournal of Dairy Research, 1978
- The acceleration by cationic materials of the coagulation of casein micelles by rennetJournal of Dairy Research, 1977
- An improved method for the quantitative fractionation of casein mixtures using ion-exchange chromatographyJournal of Dairy Research, 1977
- The quantitative measurement of whey proteins using polyacrylamide-gel electrophoresisJournal of Dairy Research, 1976
- New methods for the determination of rennin activity with .KAPPA.-casein.Journal of Nutritional Science and Vitaminology, 1975
- Effect of varying enzyme concentration on the action of rennin on whole milkJournal of Dairy Research, 1972
- Structure of the casein micelle. A proposed modelJournal of Dairy Research, 1970
- The action of rennet on whole milkJournal of Dairy Research, 1969
- Das Lab und seine Wirkung auf das Casein der Milch. X. Eine Methode zur direkten Bestimmung der Geschwindigkeit der Primärreaktion der Labgerinnung der MilchHelvetica Chimica Acta, 1955
- 176. The Determination of the nitrogen distribution in milkJournal of Dairy Research, 1938