鲜切水果磁电方法益生菌增效研究  

Enrichment of Probiotics in Fresh-cut Fruits Using Magnetic-electric Process Method

作　　者：杨哪[1] 金亚美[1] 徐悦[1] 徐学明[1,2] 金征宇[1,2] 

机构地区：[1]江南大学食品学院,无锡214122 [2]江南大学食品科学与技术国家重点实验室,无锡214122

出　　处：《农业机械学报》2016年第2期258-263,322,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：'十二五'国家科技支撑计划项目(2012BAD37B00)

摘　　要：为实现鲜切水果的益生菌富集,将感应交变电场施加于浸渍溶液体系,同时在旋转磁场的影响下有效促进溶液中鼠李糖乳杆菌向鲜切苹果和草莓渗透,考察了浸渍时体系场强、电场频率、磁场强度和频率、环境p H值和温度对样品中鼠李糖乳杆菌数的影响,发现体系场强和磁场强度越高则越有利于菌体在样品中的扩散和渗透,体系场强3 V/cm,磁场强度0.13 T时可获最高的菌数含量,即鲜切苹果和草莓菌体浓度可达9.23×108个/g和1.22×108个/g,较低的p H值环境同样有利于菌体在样品中的富集,但环境p H值为6.9和8.1时,在试样期内其各自样品中最高菌体浓度分别只有4.32×108个/g和5.4×107个/g,即低于酸性环境下获得的活菌数,处理鲜切苹果时存在最适电场频率和磁场频率各自分别为200 Hz和1 Hz,该研究为益生菌在鲜切果蔬中的快速富集提供了一种参考方法。Probiotic enrichment in fresh-cut fruits was achieved in the impregnation system when induced alternating electric field was used in conjunction with rotating perpendicular magnetic field. The method was intended to promote the efficiency of Lactobacillus rhamnosus diffusion into the tissues of apples and strawberries based on the experimental transformer structure. The amount of probiotic in the sample tissues was investigated under the influence of voltage levels（ 1 V / cm,2 V / cm,3 V / cm）,voltage frequencies（ 50 Hz,200 Hz,400 Hz）,magnetic field intensities（ 260 Gs,900 Gs,1 300 Gs）,rotating magnetic frequencies（ 0. 1 Hz,1 Hz,10 Hz）,temperature（ 20℃,40℃,60℃,80℃） and the p H values（ 3. 2,3. 5,4. 6,5. 5,6. 9,8. 1,10. 7） of the impregnation solutions. It was demonstrated that high voltage levels and magnetic field intensities were conducive to the diffusion of probiotics into the sample tissues. The highest amount of probiotic in the sample tissues was achieved at system voltage of3 V / cm and magnetic field intensity of 1 300 Gs. The maximum amounts of probiotic in fresh-cut apples and strawberries were increased to 9. 23 × 108 CFU / g and 1. 22 × 108 CFU / g,respectively. Impregnation solutions with low p H values were conducive for the accumulation of probiotics in the samples. The highest amounts of Lactobacillus rhamnosus were 4. 32 × 108 CFU / g and 5. 4 × 107 CFU / g in the fresh-cut apples and strawberries,respectively,during processing at p H values of 6. 9 and 8. 1 which showed lower living bacterium content in fresh-cut fruits compared with the samples in the acidic impregnation solution.The optimal electric field frequency and magnetic field frequency for impregnation treatment of fresh-cut apples through this magnetic-electric method were at 200 Hz and 1 Hz,respectively. The proposed impregnation method can provide a reference for probiotic enrichment of fresh-cut fruits.

关 键 词：鲜切水果 益生菌增效 磁电方法 

分 类 号：TS255.54[轻工技术与工程—农产品加工及贮藏工程]