摘要
研究了单独超声波(US)及超声波结合乳酸链球菌素(nisin)(US+nisin)对胡萝卜汁中自然菌群的杀菌效果。采用处理温度0~50℃,超声波频率20 k Hz,超声波功率密度分别为242,605,968 W/cm2,超声波处理时间0~10 min。结果表明,US能有效钝化胡萝卜汁中的自然菌群,随着处理温度和处理功率密度的升高及处理时间的延长,菌落总数、霉菌和酵母菌均显著性下降(P<0.05);胡萝卜汁在605 W/cm2,30℃处理10 min时,US和US+nisin使菌落总数下降了1.78和2.39个对数值,使霉菌和酵母菌下降3.99个对数值;当处理温度为30℃时,US+nisin比单独US的杀菌效果好,表现出对菌落总数的叠加杀灭效果,两种处理对胡萝卜汁中霉菌和酵母菌的杀灭效果无显著性差异(P>0.05)。结论:US与nisin结合使用可增强对胡萝卜汁中菌落总数的杀菌效果。
The effect of ultrasound alone(US) and ultrasound combined with nisin(US+nisin) treatments on the inactivation of naturally occurring microorganisms in carrot juice was investigated. In the study, the treatment temperature was 0 to 50 ℃; the ultrasound frequency was 20 k Hz, the ultrasound power densities were 242 W/cm^2, 605 W/cm^2, 968 W/cm^2, and the treatment time was 0 to 10 min. The total plate counts(TPC), yeasts and molds(YM) decreased when temperature, ultrasound power and treatment time increased. When fresh carrot juice was treated at 605 W/cm^2 and30 ℃ for 10 min, 1.78 and 2.39 lg cycles reduction in TPC was achieved by US and US+nisin treatments, respectively,while 3.99 lg cycles reduction in YM was observed by both treatments. When the treatment temperature was 30 ℃,US+nisin treatment had a better inactivation effect on TPC than US treatment. However, there was no significant difference on the inactivation of YM between two treatments. The results showed that the combination of US and nisin had an addition inactivation effect on TPC in carrot juice.
作者
毕秀芳
陈丽伊
潘泓桦
车振明
Bi Xiufang;Chen Liyi;Pan Honghua;Che Zhenming(Sichuan Key Laboratory of Food Bio-technology, College of Food and Bioengineering, Xihua University, Chengdu 610039)
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2018年第1期211-216,共6页
Journal of Chinese Institute Of Food Science and Technology
基金
国家自然科学基金-青年基金项目(31601480)
四川省高校重点实验室开放项目(szjj2016-018)