红茶色素的形成与降解作用的初步研究

Study on the Formation and Degradation of Black Tea Pigments

在红茶制造中,用铜酶抑制剂二乙基二硫代氨基甲酸钠能抑制多酚氧化酶活性24%左右,从而部分的抑制了茶叶发酵,特别是茶黄素的形成受到了抑制。采用茶叶匀浆发酵法,结果表明,非酶性氧化产物中茶黄素约为酶促氧化形成量的6.8%,茶红素约为20.6%。用茶黄素单没食子酯在纯过氧化物酶作用下,研究其降解作用,其产物用双向纸层析和紫外光谱进行分析鉴定,结果鉴别出3,4-二羟苯甲酸、咖啡酸、没食子酸和邻苯二酚等4种成分。

The activity of polyphenoloxidase could be inactivated by copper ionchelating regent-sodium diethyldithiocarbomate-by 24% during the proces-sing of fermentation,reducing the formation of theaflavins.Results ofaqueous suspension fermenting showed that non-enzymic oxidation producedabout 6.8% of the theaflavins produced by enzymatic oxidation and about20.6% of the thearubigin during the fermentation.The degradation oftheaflavin gallate was observed under the condition of purified peroxidase,and the products were analysed with paper-partition chromatography and ultraviolet spectroscopes.The products were identified as 3,4-dihyroxycinnamic acid,caffeic acid,gallic acid and catechol.