高压二氧化碳对鲜榨梨汁杀菌效果及动力学研究

Inactivation and kinetics analysis of aerobic bacteria in pear juice exposed to high pressure carbon dioxide

本文研究了高压二氧化碳(HPCD)对梨汁中细菌菌落总数的影响,并分析其杀菌动力学。结果表明:随着温度、压强升高以及处理时间延长,梨汁中细菌菌落总数显著降低(p<0.05);在相同温度和处理时间条件下,HPCD处理显著高于热处理的杀菌效果,处理温度对HPCD杀菌具有协同效应;当HPCD处理条件为30MPa、40℃、60min时,灭菌效果最佳,梨汁中细菌菌落总数的残存率降低了2.66个对数;Weibull模型能较好地拟合HPCD处理后梨汁中细菌菌落总数的失活曲线,模型动力学参数比例因子a和形状因子b随压力增加和温度升高呈现逐渐变小的规律性变化。

Inactivation and kinetic analysis of aerobic bacteria in fresh pear juice exposed to high pressure carbon dioxide（HPCD） was investigated. The result showed that the log reduction of aerobic bacteria increased with increasing temperature,pressure and treatment time significantly（p〈0.05）. At an identical temperature and treated for the same time,much more log reduction of aerobic bacteria was achieved by HPCD than by heat treatment,indicating temperature played a synergistic role during HPCD treatment. The maximum log reduction was 2.66-log and obtained at 30MPa,40℃ and 60min. The survival curves of aerobic bacteria in fresh pear juice were well fitted with the Weibull model,and model parameters such as a value（scale factor） and b value （shape factor） decreased with increasing pressure or temperature.