不同萎凋时间对云南微波干燥红茶中色素类物质含量影响的研究

Effects of Different Withering Time on the Content of Tea Pigments in Yunnan Black Tea Dried by Microwave

萎凋是决定红茶品质的红茶加工的第一道工序。为了研究有利于提升云南微波干燥红茶品质的最佳萎凋时间,试验设置了特定萎凋条件下萎凋24 h、萎凋30 h、萎凋36 h三个萎凋时间处理;通过检测三个不同萎凋时间处理加工的红茶中茶黄素、茶红素与茶褐素含量,并结合感官审评,分析三个不同萎凋时间处理对红茶中茶色素类物质含量的影响,找出有利于云南微波干燥红茶品质形成的最佳萎凋时间。结果表明:随着萎凋时间的延长,茶黄素含量呈现下降趋势,在萎凋24 h、萎凋30 h、萎凋36 h的过程中,茶黄素含量分别依次下降了25%。萎凋24 h与萎凋30 h相比,茶红素含量上升了91%;从萎凋30 h到萎凋36 h,茶红素含量下降了31%,萎凋30 h时含量最高达到7.34%。茶褐素含量随着萎凋时间的延长呈先下降后升高的变化趋势,萎凋24 h与萎凋30 h处理相比,茶褐素含量下降了11%,萎凋30 h与萎凋36 h处理相比含量上升了17%。综合来看,萎凋时间30 h处理的红茶在数据分析上与感官审评结果一致,汤色透亮,滋味浓醇鲜爽,品质最好,综合评分最高。

Withering is the first process of black tea processing,which determines the quality of black tea.In order to study the best withering time for improving the quality of Yunnan microwave dried black tea,three different withering times were set under specific withering conditions:24 h,30 h and 36 h.By detecting the contents of theaflavin,thearubin and thearubicin in black tea processed at three different withering times,combined with sensory evaluation,this paper analyzed the influence of three different withering times on the content of tea pigments in tea.The results showed that the content of theaflavin decreased with the extension of withering time.In the process of withering for 24 h,30 h and 36 h,the content of theaflavin decreased by 25%.Compared with 30 hours of withering,the content of thearubin increased by 91%in 24 hours of withering,decreased by 31%in the process of 30 hours to 36 hours of withering,and reached the highest content of 7.34%in 30 hours of withering.With the extension of withering time,the content of theabrownine decreased first and then increased.The content of theabrownine decreased by 11%after 24 hours of withering compared with 30 hours of withering,and increased by 17%after 30 hours of withering compared with 36 hours of withering.In a word,the black tea treated with 30 h withering time is consistent with the sensory evaluation results in data analysis.The color of the soup is bright,the taste is thick,mellow and fresh,the quality is the best,and the comprehensive score is the highest.