羔羊皱胃酶凝乳特性的研究  

Investigation on the Milk-clotting Properties of Kid Rennet

作　　者：徐明生[1] 王毕妮[1] 张富新[1] 

机构地区：[1]陕西师范大学食品工程系,陕西西安710062

出　　处：《华北农学报》2005年第6期103-106,共4页Acta Agriculturae Boreali-Sinica

基　　金：陕西省自然科学基金资助项目(2003C134);陕西师范大学重点科研资助项目(2002-12)

摘　　要：对羔羊皱胃酶的凝乳特性进行了研究.结果表明,皱胃酶的最适作用温度为50℃,低于40℃酶稳定性较好,60℃处理10 min,酶活完全丧失.在乳pH 5.5～7.5之间,随乳pH的增大而降低,当pH达到7.5时酶活近乎完全丧失;酶液在pH 2.0～7.0之间处理20 h后,酶活还保持稳定.Al3+,Ca2+和Na+对皱胃酶有较强的促凝乳作用,K+,Mg2+,Mn2+,Fe3+无较明显的促进和抑制凝乳作用,而Cu2+和Zn2+有明显的抑制酶活的作用.并研究了底物浓度对酶活的影响,得出羔羊皱胃酶催化反应的米氏常数Km为1.893g/L.The milk-clotting properties of kid rennet were investigated in the paper. The results showed that the optimum clotting temperature of kid rennet was 50℃. The milk-clotting activity of rennet was stable at less than 40℃, after 10min treatment at 60 ℃, it would completely lose. The milk-dotting activity decreased with the increase of milk pH value between 5.5 and 7.5, at pH 7.5 it almost losed completely. Treating kid rennet for 20 hours at the pH in the range of 2.0～7.0, the dotting activity maintained stable. Al^3＋ , Ca^2＋ and Na^＋ had obvious functions to accelerate milk coagulation. K^＋ , Mg^2＋ , Mn^2＋ and Fe^3＋ had no obvious functions to accelerate or inhibit milk coagulation. But Cu^2＋ and Zn^2＋ could keep milk from coagulating. The influence of milk concentration on enzymatic activity was also studied, obtaining the Km of kid rennet was 1. 893 g/L.

关 键 词：羔羊皱胃酶 凝乳活性 

分 类 号：S512.01[农业科学—作物学]