不同杀菌方式对梨枣汁贮藏过程中品质变化的影响

Effect of Different Sterilization Methods on Quality of Pear Jujube Juice During Storage

以梨枣汁为材料,探讨不同杀菌方式对贮藏过程中其主要理化性质的影响。结果表明,梨枣汁经三种杀菌方式处理后在贮藏过程中,可滴定酸、褐变程度和总色差值逐渐升高,透光率变化不显著,pH值、总糖和Vc呈下降趋势。在贮藏过程中超高压杀菌处理可有效抑制微生物生长,不同杀菌方式对梨枣汁在贮藏过程中Vc含量影响存在显著性差异。超高压杀菌处理对梨枣汁灭菌率和Vc保留率分别达93.24%和95.87%,微波杀菌处理对梨枣汁在贮藏过程中可溶性固形物和总糖含量分别维持在17.50～18.50%和0.21～0.24 mg/mL。巴氏杀菌处理对梨枣汁在贮藏过程中非酶褐变指数影响显著;在相同贮藏温度下,贮藏时间越长,超高压杀菌、微波杀菌可有效抑制梨枣汁褐变程度。在梨枣汁贮藏过程中超高压杀菌处理不仅能抑制微生物繁殖,而且能保持好梨枣汁风味、色泽和营养成分。

The effect of different sterilization methods on the physic-chemical properties of jujube juice was investigated during long-term cooling storage. The results showed that titratable acidity, browning degree and total color aberration increased gradually and transmittance of jujube juices changed slightly. Total sugar, Vc and pH showed a decreasing trend. Different sterilization methods showed significant effect on Vc and microorganisms during storage. The microorganisms in jujube juice under ultra-high pressure sterilization were reduced by 93.24% and Vc content was retained as 95.87%. The soluble solids and total sugar of jujube juice lreated by microwave sterilization were within the range of 17.50～18.50% and 0.21～0.24 mg/mL, respectively. When jujube juices were stored at the same temperature, the ullra-high pressure sterilization and microwave sterilization effectively inhibited the browning degree of juice, resulting in longer storage time. It was concluded that ulWa-high pressure sterilization can inactivate the microorganisms and maintain original fi＇uit taste, color and nutrients of pear jujube juice ditring long storage.