Development of new fermented tea by mixed kneading of third crop of green tea leaves and loquat leaves

Abstract

The third crop of green tea leaves contains a relatively large amount of catechins, giving its hot-water extract a bitter taste. The loquat leaves have strong enzymatic activity of catechin oxidization and contain chlorogenic acid which accelerates this oxidation. We investigated the production method of fermented tea by mixed kneading of the third crop of green tea leaves and loquat leaves and examined the most appropriate time to harvest green tea leaves. Fresh green tea leaves (27 kg) were withered by blowing air over them (70°C) for 20 min in a primary tea-rolling dryer. The tea leaves were then mixed with fresh loquat leaves (3 kg) and kneaded with a tea roller at room temperature for 20 min. The amount of catechins in the green tea leaves was decreased by this process, resulting in hot-water extract of mixed tea leaves that was bright red and had improved taste and aroma. The best quality fermented tea was produced from the third crop of green tea leaves harvested 35 days after the second crop harvest. We established a new production method to manufacture fermented tea by mixed kneading of the third crop of green tea leaves and loquat leaves using a primary tea-rolling dryer and tea roller. Using this method, good quality fermented tea was manufactured.