Biochemical Differentiations among Three Yongtai Green Teas

Objective Differential biochemical compositions of three varieties of tea cultivars in Yongtai, Fujian, were analyzed for germplasm preservation and marketing promotion.

Method A comprehensive evaluation on Camellia sinensis cv. ‘Fuding Dabaicha’, ‘Longjing 43’, and ‘Baiye 1’ was carried out based on sensory evaluation, biochemical determination, and multivariate statistical correlation, principal component, cluster, and partial least squares-discriminant analyses.

Result The contents of water extract in the three varieties of tea ranged 48.07%-49.53%, polyphenols 18.43%-22.19%, total catechins 72.62-107 mg·g⁻¹, caffeine 20.43-28.42 mg·g⁻¹, and total free amino acids 51.49-59.96 mg·g⁻¹. There were 21 free amino acids, including 28.68-32.86 mg·g⁻¹ of theanine, detected in them. The biochemicals in the teas were significantly similar among the teas, and the five principal components constituted a cumulative variance contribution rate of 87.77%. The clustering analysis based on the biochemical composition classified the teas into three categories. The A-class tea contained high contents of water extract, polyphenols, and catechins, while the B- and C-classes had high contents of individual and total amino acids. The classification was consistent with the results obtained by sensory evaluation.

Objective All three tea cultivars from Yongtai were considered suitable for making high-quality green tea with high water extract, amino acids, and theanine. In comparison, Longjing 43 and Anji Baicha had greater contents of individual amino acids, total amino acids, and tea polyphenols than Fuding Dabaicha, whereas Anji Baicha topped the three varieties on catechins.