汉中茶叶氨基酸含量测定及营养价值评价分析

为了解汉中茶区不同品种茶叶的营养成分,采用氨基酸自动分析仪法对南郑县、镇巴县目前种植的五种茶树品种中的氨基酸含量进行测定。结果表明,共检测出31种氨基酸,总含量(以干质量计)分别为中茶102 60.43 mg·g~(-1)、中茶108 66.14mg·g~(-1)、名山131 51.17mg·g~(-1)、乌牛早66.15mg·g~(-1)、南郑县紫阳群体种27.92mg·g~(-1)、镇巴县紫阳群体种33.45mg·g~(-1);必需氨基酸共7种,乌牛早中必需氨基酸含量最高,为2.83 mg·g~(-1);中茶108中茶氨酸含量最高,达53.73mg·g-1,占总含量93.6%;比较不同品种茶叶的氨基酸比值系数分(SRC)发现,中茶108、中茶102的SRC值最高,达68.504和62.663,营养价值高且均衡。综合比较,新引进品种的营养价值优于群体种。

Determination and Nutritional Evaluation of Amino Acids from Different Varieties of Hanzhong Tea

In order to evaluate the nutritional value of tea,amino acid compositions of five kinds of fresh tea leaves from major production regions such as Nanzheng,Zhenba in Hanzhong were analyzed by using automatic amino acid analyzer.The results showed that there were 31 amino acids identified in Honzhong tea,the total contents(dry weight)were Zhongcha 102 of 60.43mg·g~(-1),Zhongcha 108 of 66.14mg·g~(-1),Mingshan 131 of 51.17mg·g~(-1),Wuniuzao of 66.15mg·g~(-1),and the native species of 27.92mg·g~(-1) and 33.45mg·g~(-1) respectively.There were7 essential amino acids,the highest content was 2.83 mg·g~(-1) in Wuniuzao.The highest content of theanine was53.73mg·g~(-1),accounting for 93.6% of the total content in Zhongcha 108.Zhongcha 108 and Zhongcha 102 had the highest coefficient of amino acid ratio of 68.504 and 62.663.By comprehensive comparison,the newly introduced varieties are superior to native species in nutritional value.