萎凋叶含水量对南川大树茶红茶品质的影响  

Effects of the Water Content in Withered Leaves on the Quality of Camellia nanchuanica Black Tea

作　　者：杨杰 张绍绒 张琦 张成 罗理勇[1] 曾亮[1] YANG Jie;ZHANG Shaorong;ZHANG Qi;ZHANG Cheng;LUO Liyong;ZENG Liang(College of Food Science,Southwest University,Chongqing 400715,China;Economic Crop Technology Extension Center of Nanchuan District,Nanchuan Chongqing 408499,China)

机构地区：[1]西南大学食品科学学院,重庆400715 [2]重庆市南川区经济作物技术推广中心,重庆南川408499

出　　处：《西南大学学报（自然科学版）》2024年第3期54-69,共16页Journal of Southwest University(Natural Science Edition)

基　　金：国家重点研发计划项目(2022YFD1600805);重庆市技术创新与应用发展专项(cstc2020jscx-tpyzxX0009);茶资源拓展利用功能研究室专项(2022[8]号)。

摘　　要：南川大树茶是重庆的特色茶树资源,所制红茶滋味甘醇甜爽,甜香浓郁.由于其叶大节间长、表皮蜡质厚等特点,很难在萎凋过程中科学把控萎凋叶的含水量.为明确南川大树茶红茶萎凋时的最佳含水量,以南川大树茶春季1芽2叶为原料,经相同加工工艺将含水量为68%,62%和56%的萎凋叶制成红茶,通过感官审评和熵权TOPSIS评价成品茶的品质特征,并测定加工过程中的滋味、色泽和酶活变化.结果表明:加工过程中萎凋叶含水量与POD酶活性呈显著负相关(r=-0.571),萎凋叶含水量为56%时酶活性最强,此时茶多酚、儿茶素和茶色素的变幅最大,滋味浓厚度下降.感官审评结果表明:62%含水量萎凋叶所制成品红茶与68%和56%相比,干茶色泽黑润亮,滋味甜醇浓厚,香气持久纯正.其游离氨基酸总量(6.21%)、茶红素(3.37%)、L^(*)和a^(*)值均高于68%和56%含水量萎凋叶所制红茶.成品茶中共检测出79种香气物质,62%含水量萎凋叶所制红茶香气质量分数(3119.61μg/kg)高于68%和56%,其中赋予茶汤花香和果香的香叶醇、芳樟醇、橙花醇和苯乙醇质量分数高于68%和56%.进一步通过熵权TOPSIS法对检测到的滋味、香气成分进行综合评价,验证表明62%含水量萎凋叶所制红茶综合品质最佳.综上,62%含水量是南川大树茶适宜的萎凋含水量.Camellia nanchuanica is a special tea resource of Chongqing.Black tea has a sweet and refreshing taste with a strong sweet aroma.It is difficult to manage the right degree of withering during processing because of its long internodes and thick epidermis wax of leaves.To determine the optimal moisture content for the withering of black tea of Camellia nanchuanica,this study collected the one-bud and two-leaf shoots in spring to process black tea with withered leaves that had moisture contents of 68%,62%,and 56%with the same process.The taste,color,and enzyme activity were assessed during the processing.The sensory quality and entropy-weight TOPSIS analysis were employed to evaluate the black tea.The results showed that there was a significant negative correlation between the water content of withered leaves and the enzyme activity of POD(r=-0.571).The enzyme activity was the strongest when the water content of withered leaves was 56%.At this point,the variation of tea polyphenols,catechins and pigments were the largest,and the taste intensity decreased.The total free amino acids(6.21%),thearubigins(3.37%),L^(*) and a^(*) values of black tea from withered leaves with 62%water content were higher than those from withered leaves with 68%and 56%water contents.The results of sensory evaluation showed that the black tea made from withered leaves with 62%water content was darker and brighter than that made from leaves with 68%and 56%water contents.The taste was sweet and mellow,and the aroma was pure and lasting.A total of 79 aroma substances were detected in the black tea.The aroma mass fraction of black tea made with 62%water content leaves was 3119.61μg/kg,which was significantly higher than that of made from 68%and 56%water contents leaves.The mass fractions of geraniol,linalool,nerol and phenylethanol that gave the tea soup floral and fruity fragrance were higher than those of made from 68%and 56%water contents leaves.Further comprehensive evaluation of the detected taste and aroma components was conducted using th

关 键 词：南川大树茶红茶 萎凋叶含水量 品质 香气成分 

分 类 号：TS272[农业科学—茶叶生产加工] S377[轻工技术与工程—农产品加工及贮藏工程]