温压协同处理黑莓β-葡萄糖苷酶失活动力学研究  

Inactivation Kinetics of Blackberry β-Glucosidase by Combined High Hydrostatic Pressure and Temperature Treatments

作　　者：魏本喜[1] 马永昆[1] 马善丽[1] 严蕊[1] 张龙[1] 白洁[1] 

机构地区：[1]江苏大学食品与生物工程学院,江苏镇江212013

出　　处：《高压物理学报》2012年第3期281-288,共8页Chinese Journal of High Pressure Physics

基　　金：国家863计划项目(2007AA100405)

摘　　要：以黑莓β-葡萄糖苷酶为对象,研究其温压协同条件下的失活动力学规律,可为超高压食品处理技术的工业化和花色苷的保留提供有力的技术支持。实验压力为300～600MPa,温度为35～55℃。结果表明:β-葡萄糖苷酶在温压协同条件下的失活过程为两个阶段,第一阶段用瞬时失活值描述,压力和温度影响其大小,不受保压时间影响;第二阶段将β-葡萄糖苷酶分为稳定部分和敏感部分,β-葡萄糖苷酶的失活过程用双相一级反应动力学模型描述,其失活速率常数随温度、压力的升高而增大。敏感部分和稳定部分在400MPa、55℃条件下,失活速率常数KL和KS分别为2.777和0.047min-1,二者失活90%所需时间DL和DS分别为0.83和49.1min。在400MPa条件下,敏感部分的D值减少90%所需增加的温度TZ和活化能Ea分别为23.36℃和81.95kJ/mol;在45℃条件下D值减少90%所需增加的压力pZ和活化体积Va分别为1 111MPa和-5.02cm3/mol。The inactivation kinetics of β-glucosidase in blackberry were investigated at high hydrostatic pressure （300-600 MPa） combined with moderate temperature （35-55 ℃）. Analysis of the obtained kinetic data revealed a dual-effect of combined pressure-temperature inactivation： the first one, designated as an instantaneous pressure kill value （IPK）,which depended on temperatures and pressures,but was independent of treatment time; and the second one, a labile and stable fraction of β- glueosidase from blackberry are present and the inactivation kinetics of β-glucosidase by high hydrostatic pressure combined with temperatures are adequately described by the two-fraction model. The kinetic rate constants Kt. and Ks of labile and stable fractions are 2. 777 and 0. 047 min-1 , and the decimal reduction times DL and Ds are 0.83 and 49.1 min at 400 MPa and 55℃. Tz representing the needs of temperature increase for a 90% reduction of the D value and the activation energy Ea of the labile fraction at 400 MPa are 23.36 ℃ and 81.95 kJ/mol,pz representing the needs of pressure increase for a 90% reduction of the D value and the activation volume Va at 45℃ are 1 111 MPa and -5.02 cm3/mol.

关 键 词：温压协同 黑莓 Β-葡萄糖苷酶 失活 动力学 

分 类 号：O521.9[理学—高压高温物理]