어육 단백질의 기능성을 개선하기 위해 정어리 분말단백질의 pepsin가수분해물을 이용하여 plastein을 합성하기 위한 반응조건을 검토하였다. plastein합성반응 최적조건으로서는 pepsin, ${alpha}-chymotrypsin$, protease(from Aspergillus saitoi) 및 papain의 경우 PH는 각각 4, 7, 5 및 6, 기질농도는 pepsin과 ${alpha}-chymotrypsin$의 경우 40%였으나 protease와 papain은 50%였다. 온도는 4종의 효소 모두가 $50^{circ}C$였다. 기질의 가수분해도가 60%이상에서 plastin합성반응이 이루어졌으며, 가수분해도가 78.4% 이상이었을 때 plastein 생성량은 높았다.
In order to develop a new type of food source for the effective utilization of fish protein, plastein reaction was applied to improve the functional properties of sardine protein. Conditions necessary for optimal plastein productivity from sardine protein using pepsin, ${alpha}-chymotrypsin$, protease(from Aspergillus saitoi) and papain were established. Sardine protein concentrate was hydrolyzed with pepsin yielding an approximate degree of hydrolysis of 78.4%. Enzyme induced plastein was optimized at : pH 4 for pepsin, pH 7 for ${alpha}-chymotrypsin$, pH 5 for pretense and pH 6 for papain : Substrate concentrate 40% for pepsin and ${alpha}-chymotrypsin$, 50% for pretense and papain : the time of incubation, 24hr : enzymestrate ratio, 1 : 100(wv) incubation temperature, $50^{circ}C$.
