Effect of Withering Light-wave Bands on Different Varieties Black Tea Quality

The natural withering indoor was used as the control, the effect of different intensity (1000 、1500、2000 lx) of red light, yellow light and blue light on the sensory assessment quality and main components of different varieties of black tea were compared in the study. The results showed that, compared with the control, the amino acids content in fuding-dabaicha and No. 1 of shuyong withered leaf together with the theaflavins (TFs) content in sichuan-zhongxiaoyezhong black tea would be kept or promoted under all light withering, and soluble sugar content in No. 1 of shuyong and sichuan-zhongxiaoyezhong black tea would be promoted under blue light withering, while the theabrownine (TB) content in fuding-dabaicha and No. 1 of shuyong black tea would be decreased under this condition. Correlation analysis showed the soluble sugar content of fuding-dabaicha black tea, and the TB content in sichuan-zhongxiaoyezhong black tea were significantly and positively correlated with yellow light intensity, while the tea polyphenols content in No. 1 of shuyong withered leaf and its black tea were great degree negatively correlated with yellow light intensity, and the soluble sugar content in sichuan-zhongxiaoyezhong black tea was great positively correlated with blue light intensity, both were not significant. Considered the sensory assessment, the optimum withering light and intensity for fuding-dabaicha black tea was 1500 lx and 2000 lx yellow light, which would keep higher content of thearubigins (TRs) that were 2.211% and 2.049%, and lower content of TB that were 3.081% and 3.025% in tea. The 1500 lx yellow light was the optimum selection for No. 1 of shuyong black tea with the highest content of amino acids which was 2.8%. The 1500 lx yellow light and 1500 lx blue light were the best choices for sichuan-zhongxiaoyezhong black tea, the amino acids content reached to 3.4% in the former, the TFs content reached to 0.280% and the TB content was as low as 2.937% in the latter. So the 1500 lx yellow light was beneficial to promote the quality of these three kinds of black tea.