香水梨和皇冠梨果实多酚氧化酶特性的研究  

Study on the Characteristics of Polyphenol Oxidase in Pgrus ussuriensismaxim and“Huangguan”Pear

作　　者：张欣[1] 贝盏临[1] 张安东[1] 

机构地区：[1]北方民族大学生物科学与工程学院,银川750021

出　　处：《食品工业》2016年第7期219-223,共5页The Food Industry

基　　金：宁夏科技支撑项目(2012);北方民族大学专任教师基本科研项目(2015);国家级大学生创新训练计划项目(201411407037)

摘　　要：研究以香水梨和皇冠梨的果实为试材,正交设计优化提取梨果中多酚氧化酶（PPO）的3个试验因素：Tween80浓度、时间和料液比。确定最佳提取条件均：Tween 80为1.0%、提取时间为3 h,料液比为1︰2（g/mL）。得到香水梨PPO为4.755 mg/g、皇冠梨PPO含量为2.666 mg/g。在20℃±0.5℃下测定香水梨和皇冠梨的PPO活性自然活性变化,0-10 min内香水梨的PPO活性均高于皇冠梨。试验还研究了温度、pH、机械匀浆、柠檬酸、抗坏血酸、L-半胱氨酸等条件对两种梨果PPO活性的影响,结果表明：随打浆时间的延长,香水梨、皇冠梨的褐变指数均逐渐增高;香水梨、皇冠梨的PPO最适温度均为35℃;香水梨PPO最适pH为5,皇冠梨PPO最适pH为6;柠檬酸、抗坏血酸、L-半胱氨酸对香水梨、皇冠梨的PPO活性均表现出抑制作用,其中柠檬酸的抑制作用较弱。Pgrus ussuriensismaxim and ＂Huangguan＂ pear was used as tested materials. The orthogonal design optimization extraction pear fruit polyphenol oxidase （PPO） of the three experimental factors were studied. Tween 80 concentration, time, and solid-liquid ratio was determined The optimum extraction conditions were founded as followings： Tween 80 1.0%, extraction time 3 h, and material to liquid ratio 1 ： 2 （g/mL）. Under these condions, Pgrus ussuriensismaxim PPO content was 4.755 rag/g, and ＂Huangguan＂ pear PPO content was 2.666 mg/g. The activity of PPO in Pgrus ussuriensismaxim and ＂Huangguan＂ pear was determined by 20 ℃-0.5 ℃, and the activity of PPO in 0-10 rain was higher than that of＂Huangguan＂ Pear. The effect of the experiment conditions of temperature, pH, a mechanical homogenizer, citric acid, ascorbic acid, and L-cysteine, ete on two kinds of pear PPO activity were also studied. The results showed that： with the prolongation of beating time, Pgrus ussuriensismaxims, ＂Huangguan＂ peares browning index were increasing gradually; Pgrus ussuriensismaxim and ＂Huangguan＂ pear PPO optimum temperature was 35 ℃; Pgrus ussuriensismaxim PPO optimum pH was 5, ＂Huangguan＂ pear PPO optimum pH was 6; citric acid, ascorbic acid, L-cysteine on Pgrus ussuriensismaxim, ＂Huangguan＂ pear PPO activity showed inhibitory effect, of which the citric acid inhibition effect was weak.

关 键 词：香水梨 皇冠梨 多酚氧化酶 酶学特性 

分 类 号：TS255.1[轻工技术与工程—农产品加工及贮藏工程]