Immobilization of Thermolysin and Application of the Immobilized Thermolysin to Cheese-making

Thermolysin의 고정화(固定化)와 고정화(固定化) Thermolysin의 Cheese제조(製造)에의 이용(利用)

Thermolysin was immobilized on Dowex MWA-1 with 10% glutaraldehyde and incorpo rated into a fluidized-bed continuous coagulation scheme to make Cheddar type cheese. The activity yield of thermolysin was 25%. The immobillized thermolysin was stable at $60^{\circ}C$ in the presence of 1/200M calcium ions and the half-life value is 16 days at the temperature. Raw milk alkalified to pH 7.0 was passed through a column of thermolysin beads at $55^{\circ}C$, cultivated with Streptococcus cremoris and allowed to coagulate. A typical milk curd was formed to make Cheddar type cheese, avoiding troublesome microbial contamination successfully during continuous hydrolysis process. During ripening of this cheese for 6 months at $10^{\circ}C$, its ripening ratio and taste were similar to those of cheese prepared by the traditional method.

Thermolysin 을 Dowex MWA-1에 10% glutaraldehyde로 고정화하였으며, 이 고정화 thermolysin을 사용하여 연속적응유(連續的凝乳)를 행(行)하였다. Thermolysin의 고정화수율(固定化收率)은 25%이었다. 고정화 thermolysin은 1/200M $Ca^{++}\;ion$의 존재하에서 $60^{\circ}C$의 고온에서도 안정하였으며 이 온도에서의 half-life는 16일이었다. 원료 milk를 pH 7.0이 되도록 조정하여 $55^{\circ}C$로 유지된 고정화 thermolysin column을 통과 시 켜 분해시킨 후, Streptococcus cremoris를 접종하여 응유(凝乳)시켜 curd를 얻었으며, 이렇게 하므로써 미생물오염이 방지될 수 있었으며 연속적응유를 효과적으로 행할 수 있었다. 고정화 thermolysin을 사용하여 얻은 cheddar type의 cheese는 rennet을 사용한 전통적인 방법으로 만든 cheese 와 거의 비슷하였다.