Abstract:

The suitability for processing black tea of the state-level excellent tea cultivars Zhongcha 302 and Zhenong 117
which were introduced from Zhejiang province to Sichuan province was investigated in comparison with Fudingdabaicha
as the dominant cultivar mainly used for producing black tea in Sichuan province based on chemical composition and
sensory characteristics. The results showed that spring and summer shoots of two cultivars contained abundant watersoluble
substances, tea polyphenols and catechin ranging from 37.19% to 42.19%, from 20.27% to 29.50%, and from
132.95 mg/g to 157.76 mg/g, respectively, which were present in significantly lower amounts in Fudingdabaicha. The ratio
of polyphenols to amino acids ranging from 4.25 to 9.81 was higher than that of the control, suggesting that both introduced
cultivars are suitable for processing black tea. Black tea produced from the two cultivars contained abundant quantities of
internal substance with characteristic components including tea polyphenols and catechin ranging from 11.81% to 19.61%
and from 18.69 mg/g to 39.13 mg/g, respectively. Moreover, the contents of theaflavins (TFs) and thearubigins (TRs) in
the tea infusions were high, ranging from 0.63% to 0.74% and from 8.66% to 9.90%, respectively and the ratio of TR
to TF ranged from 12.97 to 14.03, providing the material basis for the strong taste and red color of tea infusion. Totally
50 aroma constituents were detected in Zhongcha 302 and Zhenong 117, including alcohols, aldehydes, ketones, esters,
alkenes, alkanes and unknown compounds, among which alcohols were the most dominant compounds with relative contents
of 64.06% and 67.23% in Zhongcha 302 and Zhenong 117, respectively. The contents of major aroma constituents such as
linalool, its oxidation products, and geraniol were significantly higher than those of Fudingdabaicha. The sensory quality of
Zhongcha 302 was similar to that of Zhenong 117 and both were significantly better than Fudingdabaicha.

Key words: introduced cultivars, black tea, components, quality