Published online by Cambridge University Press: 01 June 2009
Whole acid casein and α-, β- and γ-caseins were isolated and treated with rennin. Chemical, chromatographical and electrophoretical analyses were done on the caseins and on the products obtained from them after rennin treatment. Three different fractions were obtained which had some specific protective activity for the Ca-sensitive forms of α-, β- and γ-casein, respectively, and which differed in their chemical, chromatographical, and electrophoretical properties.
It is suggested that each casein fraction in milk is associated with its own protective fraction which when released by the action of rennin, allows the casein to clot.