中文摘要：

采用愈创木酚和邻苯二酚氧化法研究了不同热处理对青菜中过氧化物酶和多酚氧化酶活性的影响.结果表明,对青菜进行90℃4 min、95℃2 min、95℃3 min、95℃4 min的热烫处理后,青菜中过氧化物酶的活性分别为37.30、39.28、34.34、24.95,相对残余活力分别下降为8.11％、8.53％、7.46％、5.42％.95℃2min热烫处理后迅速转移到冰浴条件冷却与未冷却的新鲜青菜中多酚氧化酶的相对残余活力分别为16.49％、1.24％.因此,当青菜经95℃2min烫漂后迅速转移到冰浴条件下冷却,过氧化物酶（相对残余活力8.53％）和多酚氧化酶（相对残余活力1.24％）的活性均得到了很好的抑制,相对残余活力低于10％,而且在此烫漂条件下青菜的叶绿素质量分数（2.31 mg/g）较高,色泽（-a＊值为22.84,饱和度C＊为35.56）也比较好.

英文摘要：

In this paper,guaiacol and catechol oxidation method were used to study the effect of different blanching on the peroxidase and polyphenol oxidase activity of Brassicachinensis L.The results show that the peroxidase activity of Brassicachinensis L.respectively were 37.30,39.28,34.34,24.95 after blanching for 4 min at 90 ℃,2 min at 95 ℃,3 min at 95 ℃,4 min at 95 ℃,the relative residual dynamic activity decreased to 8.11%,8.53%,7.46%,5.42%.The polyphenol oxidase relative residual activity of Brassicachinensis L.were 16.49% after blanching for 2min at 95 ℃ without rapidly transferring to ice bath to cool.If we transferred to ice bath to cool,the polyphenol oxidase relative residual activity of Brassicachinensis L.were 1.24%.Therefore,when the Brassicachinensis L.was blanched for 2min at 95 ℃ and then quickly transferred to ice bath to cool,the activity of peroxidase （the relative residual activity was 8.53%） and polyphenol oxidase （rhe relative residual activity was 1.24%） had been well suppressed and the relative residual activity was less than 10%,what＇s more,in this blanching conditions,the content of chlorophyll was higher（2.31 mg/g）,the color （the value of-a was 22.84,the value of saturation C was 35.56） was better.