Analysis of the Quality of Keemun Black Tea Based on Cultivars Diversity

To understand the influence of cultivars on quality of Keemun black tea,Fuzao NO.2 and Shuchazao two varieties planted in Qimen were used. The fresh leaves of two varieties were manufactured by traditional processing of Keemun black tea,and the sensory evaluation and the compounds analysis were also conducted. The results showed that,the two black teas possessed the characteristic quality of Keemun black tea with bright color and honey aroma. However,two black teas had differences in the taste and fragrance. The analysis of volatile compounds indicated that the aroma compounds such as linalool,cis-hexanoic acid-3-hexenyl ester,geraniol,methyl salicylate,phenylethyl alcohol,2-hexenal and so on had greatly different in the two black tea samples,which might be the main reason for the difference in aroma quality of the two varieties of black tea. Furthermore,the analysis of catechins and caffeine showed that the amount of gallated catechins in Shuchazao black tea was lower than that of Fuzao No.2 black tea(P<0.05),but the contents of caffeine and free amino acids were higher than that of Fuzao NO.2 black tea(P<0.05),which contributed the higher quality of Shuchazao black tea. In summary,black tea processed by different varieties in the same area contained the characteristic quality of Keemun black tea,but their flavor had significant distinction due to the difference of secondary metabolic products.