酒曲发酵产凝乳酶条件优化及其凝乳特性研究  

Optimization of Fermentation Conditions for Producing Rennet from Jiuqu and Coagulation Properties of the Enzyme

作　　者：赵笑[1] 王辑[1,2] 郑喆[1] 赵爱梅[1] 孙雨辰[1,3] 杨贞耐[1] 

机构地区：[1]北京工商大学食品质量与安全北京实验室,北京100048 [2]吉林大学生物与农业工程学院,长春130012 [3]吉林农业大学食品学院,长春130118

出　　处：《中国食品学报》2017年第2期52-62,共11页Journal of Chinese Institute Of Food Science and Technology

基　　金：北京市教委科研计划重点项目(KZ201310011011)

摘　　要：采用响应面分析法对酒曲发酵产凝乳酶的条件进行优化,确定其最佳产酶条件是:酒曲接种量5.7%,发酵时间72 h,摇床转速120 r/min,在此条件下凝乳酶凝乳活力为51.05 Su/m L,与理论预测值(52.29 Su/m L)接近。与商业凝乳酶作对照,探究不同因素对酒曲凝乳酶凝乳特性的影响,结果表明:在温度30~35℃,pH 5.5~6.1范围时,酒曲凝乳酶的凝乳效果较好。随着CaCl_2和凝乳酶添加量的增加,酒曲凝乳酶的凝乳效果增强。流变学特性表明,与商业凝乳酶相比,酒曲凝乳酶的凝乳时间较短,凝乳的粘性和弹性较高。微观结构观测结果:酒曲凝乳酶可使凝乳形成连续的、不规则且较为致密的网状结构,有利于其在干酪中的应用。In this paper,fermentation conditions for the rennet production from Jiuqu were optimized by using the method of response surface analysis.The optimal conditions were as follow：Jiuqu starter content of 5.7%,fermentation time of 72.0 h,rotating speed of 120 rpm.The milk-clotting activity of the enzyme produced under the optimal condition was 51.05 Su/mL,near the theoretical value （52.29 r/min）.Further study on factors affecting coagulating properties indicated that the rennet from Jiuqu showed good curd phenomenon at the temperature from 30 ℃ to 35 ℃ and pH from 5.5 to 6.1.With the increase of CaCl2 and rennet concentration,the coagulating property of cow milk was enhanced.Rheological studies showed that the rennet from Jiuqu had less coagulation time,and the coagulum had higher viscosity and elasticity when compared to commercial rennet.The microstructure observation showed that the curd produced by coagulation with the rennet from Jiuqu had a continuous,irregular and relatively dense mesh structure,which was beneficial to its application in cheese.

关 键 词：酒曲凝乳酶 响应面 凝乳特性 流变学特性 微观结构 

分 类 号：TS252.53[轻工技术与工程—农产品加工及贮藏工程]