茶鲜叶水洗工艺研究初报

Preliminary Report of Washing Process on Fresh Tea Leaves

试验探寻了茶鲜叶水洗工艺对干茶感官品质、内含成分以及清洗水样溶解性总固体物含量和浑浊度变化的影响。结果表明,茶鲜叶水洗对干茶感官品质的影响差异不明显。不过在茶鲜叶水洗过程中,茶多酚含量下降了12%,咖啡碱、水溶性糖、水浸出物含量也有不同程度的下降,但变化不明显,而氨基酸含量基本没变化;未洗鲜叶与水洗流程的清洗、甩干、热风除水前3个阶段的鲜叶香气组分相对含量无明显的差异,鲜叶水洗后摊放阶段的苯甲醛、香叶醇、L-柠檬烯、芳樟醇、芳樟醇氧化物Ⅰ、壬醛、水杨酸甲酯、反-2-癸烯醛、己酸-顺-3-己烯酯、己酸-反-2-己烯酯、α-法尼烯、δ-杜松烯、邻苯二甲酸二异丁酯等的含量有所增加,而顺-3-己烯醇、苯乙醇、反式石竹烯的含量则有所下降。清洗后水中的溶解性总固体物含量上升了21.6%,浑浊度是对照的11.5倍。

The effects of water washing of fresh tea leaves on the sensory quality and chemical components of dry tea,total dissolved solids content and turbidity changes in cleaning water were studied.The results showed that water washing of fresh tea leaves had little effect on the sensory quality of dried tea.However,during the water washing process,the content of tea polyphenol decreased by 12%;caffeine,water soluble sugar,water extracts also decreased at varying level which was not obvious;and the amino acid content did not change.During the first 3 stages of washing process,washing,drying and hot water removing,the fresh leaf aroma components showed no difference to the tea leaves not washed.In the spreading stage after washing,the content of benzaldehyde,geraniol,L-limonene,linalool,linalool oxide Ⅰ,nonyl aldehyde,methyl salicylate,trans-2-decene aldehyde,caproic acid-cis-3-hexenyl ester,hexanoic acid-trans-2-hexenyl acetate,α-farnesene,δ-cadinene,phthalate diisobutyl increased;while the content of cis-3-hexenol,phenyl ethanol,and trans-caryophyllene declined.After cleaning,the content of total dissolved solids in water increased by 21.6%;and the turbidity was 11.5 folds of that of CK.