贮藏温度对优质绿茶品质劣变的影响

Influence of storage temperature on quality worsening of excellent green tea

以优质绿茶为原料,进行为期12个月的贮藏试验,研究贮藏温度对优质绿茶品质劣变的影响.结果表明,-15,0,4℃及室温下贮藏10个月后,优质绿茶的物理性状、品质成分含量、感官品质都有下降或劣变.茶汤明暗度表征量L,茶汤透光率T640值逐渐下降,茶汤红绿色度表征度a,茶汤黄蓝色度表征度b值逐渐上升且增幅较大;氨基酸、茶多酚、咖啡碱、水浸出物、儿茶素、简单儿茶素、酯型儿茶素的含量下降,含水量上升,感官品质下降,不同温度间差异显著.贮藏温度越低,优质绿茶的品质成分保留量越多,感官品质保持得越好.

By using an excellent green tea as material, storage experiments which lasted 1 2 months were carried out. The results showed that the main physical characters, contents of quality components and sensory quality of the excellent green teas were declined after they were stored for 10 months under different temperatures. The values of L, T640 of the tea liquor declined continuously while the values of a, b increased continuously and quickly. The content of quality components, such as amino acid, tea polyphenols, caffeine, water extracts, total catechins, simple catechins and estered catechins all reduced while the content of moisture increased and the sensory quality deteriorated. A notable difference exists among different samples stored at different temperature. The general trends are that the lower the storage temperature is the more the contents of quality components are reserved and the better sensory quality is maintained.