高静压对桃汁杀菌、钝化酶活性的效果

Inactivation of Microorganisms and Enzymes in Cloudy Peach Juice by High Hydrostatic Pressure

研究在不同处理压力和时间条件下,高静压加工技术对桃汁中微生物(细菌总数、霉菌、酵母菌、大肠菌群)以及酶(多酚氧化酶、果胶甲基酯酶、脂肪氧化酶)的影响。结果表明:经400MPa、5min高静压处理即可完全杀灭桃汁中的微生物;在400MPa和500MPa条件下,桃汁中的多酚氧化酶和脂肪氧化酶的活性出现了不同程度的激活现象,但在600MPa时,随着处理时间的延长,其活性逐渐降低,经30min处理后,分别被钝化了0.7662和0.641。而果胶甲基酯酶在400、500、600MPa条件下,出现了不规律的激活或钝化现象。另外,研究表明在高静压加工前增加漂烫工艺,可以有效杀灭桃汁中的微生物及钝化酶活性。

The effect of high hydrostatic pressure（HHP） on inactivation of microorganisms,including total aerobic bacteria（TAB）,yeasts and molds,coliform microflora and enzymes,including polyphenol oxidase（PPO）,pectin methylesterase（PME）,lipoxidase（LOX） in cloudy peach juice was investigated in this study.All these microorganisms were completely inactivated by HHP at 400 MPa and 5 min.The PPO and LOX were activated by HHP at 400 MPa and 500 MPa,but inactivated at 600 MPa.Longer treatment time resulted in more inactivation.Both enzymes were inactivated by 0.7662 and 0.641,respectively at 600 MPa and 30 min.However,the PME in cloudy peach juice was irregularly changed at 400,500 MPa and 600 MPa.Furthermore,applied blanching before HHP treatment proved effective in inactivating the microorganisms and enzymes in cloudy peach juice.