川红工夫加工过程多酚类物质及其相关酶的变化规律

Changes in Polyphenols and Enzymes Responsible for Their Formation during Processing of Chuanhong Gongfu Tea

以四川小叶种群体品种的一芽二叶为原料,采用传统工艺制备川红工夫,检测其茶多酚、黄酮、儿茶素、茶黄素、茶红素的含量,以及多酚氧化酶和过氧化物酶活性的变化,分析多酚类化合物含量与其形成相关酶活性之间的关系。结果表明:茶多酚和儿茶素含量在加工过程中呈现下降趋势;黄酮、茶黄素和茶红素含量在揉捻阶段显著增加,黄酮和茶黄素含量在发酵过程中较揉捻时降低;多酚氧化酶和过氧化物酶活性在揉捻阶段呈较显著下降趋势。通过相关性分析发现:茶多酚含量与多酚氧化酶(polyphenoloxidasePPO和过氧化物酶(peroxidasePOD活性之间存在极显著正相关;茶黄素含量与POD活性呈极显著负相关;茶红素含量与POD活性及PPO活性分别呈极显著和显著负相关。适当延长揉捻时间和减少发酵时间,或是在发酵过程中采用提高多酚形成相关酶活性的方法,可制备出高茶黄素含量的川红工夫。

Chuanhong Gongfu tea was made by the traditional process from one bud with two leaves from a small-leaf variety in Sichuan. The contents of tea polyphenols, flavonols, catechins, theaflavins, thearubigins, and the activities of polyphenoloxidase and peroxidase in Chuanhong Gongfu tea were investigated to study the correlation between the contents of tea polyphenols and the activities of the enzymes responsible for their formation. The results showed that the contents of tea polyphenols and catechins displayed a downward trend whereas the contents of fl avonols, theaavins and thearubigins at the rolling stage increased significantly, and the activities of polyphenoloxidase and peroxidase decreased. However,the contents of fl avonols and theaavins during the subsequent fermentation process declined. There were signicant or extremely signicant correlations between the contents of tea polyphenols and the activities of the enzymes responsible for their formation during the manufacturing process of Chuanhong Gongfu tea. High contents of theaavins in Chuanhong Gongfu tea can be achieved by prolonging the rolling time and reducing the fermentation time, as well as by improving the activities of the enzymes related to polyphenols formation.