Abstract:
4 levels and 5 factors were used in the orthogonal test to investigate the effect of baking temperature and time on quality of Dangui Oolong tea from southern Fujian. The results showed that treatments of A
4B
1C
4D
2E
3 and A
3B
2C
4D
3E
1 produced teas of the highest quality. The brewed tea was golden and bright soup, lightly scented with slight sweetness in aroma, or with floral aroma,and mellow in taste. The tea baking was carried out in 3 stages:the first done with a higher temperature to eliminate off-flavors, the second with a lower temperature and longer time to generate flavoring components in teas, and the last with a higher temperature to accentuate the aroma. The optimal temperature and time for the 3 baking stages were found to be 120℃ for 20 min, 90℃ for 130 min, and 120℃ for 30 min. An alternative process was called for 110℃ for 30 min, 90℃ for 140 min, and 130℃ for 10 min. The biochemical composition in tea was also altered during baking. The contents of caffeine and water extracts were significantly increased. The orthogonal experiment indicated that, as far as baking was concerned, the third stage affected the tea quality most significantly.