灭菌与老化处理对绿茶鲜汁饮料品质的影响

Effect of Heat Sterilization and Storage on Quality Attributes of Fresh Green Tea Beverages

研究了灭菌和老化处理对绿茶鲜汁饮料色差、感观品质及主要生化成分影响。结果表明,高温灭菌和老化处理过程中汤色黄度增加,明度和绿度降低,苦涩味、收敛性降低,滋味趋于醇和;而茶多酚、游离氨基酸总量基本不变,咖啡因呈现逐步降低趋势,表儿茶素降低,儿茶素升高。饮料品质的变化是主要是儿茶素类等物质剧烈变化引起的。不同原料的绿茶鲜汁饮料在灭菌和老化过程中品质变化表现出差异性。

Effect of heat sterilization and storage on quality attributes of fresh green tea beverages was studied. The results showed that the lightness and greenness of the infusions decreased with the treatments of heat sterilization and storage whereas the yellowness increased. The concentration of tea polyphenols and amino acids did not correspondingly change with the colors, but the concentration of caffeine in the beverage decreased during storage. Among the major catechins, EGCG、ECG、EGC decreased, and GCG、CG、GC increased with heat sterilization and storage treatments. The changes in quality attributes of the different beverages could be due to variation in content of tea catechins, amino acid and caffeine.