Analysis of Quality Components in Black Tea from Middle and Lower Reaches of Yangtze River

Sensory evaluation combined with the physical and chemical components and aroma components analysis of black tea collected from middle and lower reaches of Yangtze River have been successfully applied to extract the taste and aroma quality related information. The result showed that quality characteristics of black tea from middle and lower reaches of Yangtze River were sweet aroma,sweet potato aroma,sweet alcohol and other aromas and tastes. High content of water extract,caffeine and terpenol,with the proportion of thearubigins to theaflavins between 1:10 and 1:13,jointly formed the foundation for red and bright tea soup,mellow taste and sweet aroma of black tea from middle and lower reaches of Yangtze River. High content of soluble sugar and thearubigins in Hubei black tea have laid the material basis of red and bright tea soup,sweet and pure taste. High content of water extract,tea polyphenols,caffeine,flavonoids,catechins,theaflavin and thearubigins in Hunan black tea have laid the material basis of deep red tea soup and thick taste. High content of amino acids and soluble sugar in Zhejiang and Anhui black tea have laid the material basis of sweet and pure taste. The major aroma compounds were alcohols and aldehydes. Characteristic aroma components including linalool,linalool oxide,geraniol,benzaldehyde,benzeneacetaldehyde,2-methylbutyraldehyde,2-hexenal,β-cyclocitral,methyl salicylate,and β-ionone together laid the foundation for the sweet,sugar and flower aroma of black tea. Furthermore,2-pentylfuran,2-ethylfuran and 1-ethyl-2-formyl pyrrole present nuts and burnt flavor,which have direct effects on the formation of camerlsed aroma of black tea.