Abstract: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 treated 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 ultra-high pressure sterilization and microwave sterilization effectively inhibited the browning degree of juice, resulting in longer storage time. It was concluded that ultra-high pressure sterilization can inactivate the microorganisms and maintain original fruit taste, color and nutrients of pear jujube juice during long storage.
