Degradation of Milk Proteins by Extracellular Proteinase From Brevibacterium Linens Flk-61

Abstract

The objective of this study was to investigate the specificity of an extracellular proteinase from Brevibacterium linens FLK-61 on the degradation of milk proteins (a(s1)-, beta-casein, sodium caseinate and whey proteins). Each protein and the enzyme solution were incubated at 45 degrees C for "0" 15 and 30 min and 1, 2, 3, 4 and 5 h. After that, hydrolysis of the proteins was evaluated by urea-PAGE electrophoresis and densitometry. It was found that the enzymatic degradation of alpha(s1)-casein occured much faster and it was more complete (P<0.01) than degradation of beta-casein. No degradation of whey proteins was found during 5 h incubation.