Effect of Leaf Maceration and Withering Duration on Selected Tea Quality Parameters-A Case of Non-aerated Teas from TRFK 306 and TRFK 6/8 Clones

Abstract

Leaf maceration and withering are processing steps that influence tea quality. The current study involved two tea clones, TRFK 306 and TRFK 6/8. Assessment was done on the effects of these steps on total monomeric anthocyanins (TMA), total soluble solids (TSS) and the tasters’ comments. The tea leaves were processed by orthodox (rolling) and Cut, Tear and Curl (CTC) manufacture methods and withered at an interval of 5 hours. TMA were assayed following Giusti and Wrolstad protocol while TSS was determined by weight differential method. Experienced tea tasters participated in the sensory exercise. Data was subjected to general linear model using SAS package version 9.1.3. Both CTC and orthodox non-withered teas had 93 mg/L residual anthocyanins while long withered teas had lower levels averaging 24 mg/L. TRFK 306 non-withered orthodox and CTC teas had 3.2 mg/ mL and 3.43 mg/mL TSS, respectively, while those withered for 20 hours and processed by both methods had 3.5 mg/mL and 3.23 mg/mL TSS, respectively. TRFK 6/8 none withered orthodox and CTC teas had 4.29 mg/mL and 3.62 mg/mL TSS, respectively while those withered for 20 hours had 3.62 mg/mL and 3.51 mg/mL TSS, respectively. The colour score for non-withered TRFK 306 orthodox and TRFK 6/8 teas was 3.33 and 3.00 respectively, while teas withered for 20 hours from both clones had 4.00 and 3.67 colour scores. It was established that leaf maceration style does not affect TMA and long withering duration reduces the levels of anthocyanins. TRFK 6/8 had more TSS than TRFK 306 irrespective of processing method. Rolling and withering improves the liquor colour of teas.