名优茶杀青叶冷冻存贮研究

对名优茶杀青叶进行冷冻存贮,研究其贮藏中主要生化成份、香气等的变化。结果表明:杀青叶在冻贮期间,其氨基酸总量、茶多酚含量的变化均达显著、极显著水平,与存贮的成品茶生化成份的变化基本一致,但其主要生化成份特别是茶多酚含量的变化滞后于成品茶,这说明杀青叶冻贮期间,其内部生化反应速度低于成品茶存贮。杀青叶冻贮6个月后,其香气成份的保留量高于成品茶26.86%,特别有利于香气成份的保存,这可能与杀青叶存贮中保存了大量的香气前体物有关。冷冻杀青叶的解冻等后加工过程对茶叶生化成份、香气等有较大影响,以微波方式快速解冻对茶叶品质最有利。

Study on the Frozen Storage of De-enzyming Leaf of Quality-tea

The changes of main biochemical components and aroma in de-enzyming leaf of quality-tea were studied during its frozen storage. Results indicated that changes of its total amino acids and its tea polyphenols reached distinct or extremely distinct levels during the frozen storage. It is consistent with the changes of the biochemical components in made tea, but the changing speed, especially the tea polyphenols, is slower in de-enzyming leaf than in those in made tea. This expressed that the biochemical reaction within tea leaves is lower in de-enzyming leaf than that in made tea. After stored six months, the remaining percentage of aromas is 26.86% higher in de-enzyming leaf than those in made tea. The frozen storage of de-enzyming leaf is particularly favorable to the preserving of aromatic compounds. This probably related to a lot of the precursor of aroma was stored in de-enzyming leaf during the storage. The late processing of the frozen de-enzyming leaf, unfreezing for example, influenced the biochemical components and aroma of tea. Quick unfreezing with microwave is more favorable the tea quality.