در پيچش دهي برگ هاي چاي CTC الگوي تغييرات تيافلاوين در چاي سياه -ايران - ارزيابي روش هاي سنتي و

PATTERN OF THEAFLAVIN CHANGES IN IRANIAN BLACK TEA-EVALUATION OF THE CTC AND CONVENTIONAL PROCESS IN THE ROLLING OF GREEN TEA LEAVES

Oxidative fermentation of tea leaves as an enzymatic process plays a definite role in the quality of black tea. In the present study, the optimized time of fermentation for Iranian black tea was determined. The results obtained were discussed in terms of measured theaflavin (TF), the major pigment formed during black tea manufacture. The effect(s) of the tea quality was studied: the traditional and CTC (Cut, tear, curl as the newer method) of the tea leaves tissue disintegration were compared. Iso-butyl-methyl ketone as the solvent of choice (i.e. as mentioned in the literature) was used to extract TF and other black tea liquor content. These con-tents were measured using the spectrophotometric method ( A =380 nm). The results were analyzed using nonlinear regression. The fitted equation obtained may predict the changes of chemical variables in black tea and the importance of these changes on tea quality were discussed in terms of the correlation coefficient.