68. Impact of temperature and fermentation period on the overall quality of black tea
Abstract
Black tea processing fermentation was studied at different temperatures and times. Time and temperature have a significant effect on the aflavin content of black tea. Highest mean percentage of the aflavin (0.53%) was recorded at 20-210C while the lowest percentage (0.41%) was seen at 28-29 0C. Significant effect was also found on the the arubigens where maximum mean value (17.36%) was found at 180 minutes and minimum (15.97%) at 100 minute. Time and temperature have a significant effect on TSS. Maximum mean value (36.47%) was recorded at 120 minutes and minimum (33.90%) at 180 minute. On caffeine and acidity, there was no significant effect of time and temperature. However, the significant effect was found on quality, hue and thickness. For quality, maximum mean score (4.52) was noticed at 100 minute and minimum (4.22) at 180 minute at 20-21 0C highest mean score (4.57) and the lowest score (4.28) at 28-29 0C was observed. Maximum and minimum mean hue score was (4.43) and (4.06) at 120 minutes and 100 minutes respectively. While at 28-29 0C highest mean scores (4.53) and lowest, score (3.99) at 24-25 0C was recorded. Maximum mean score (3.94) and minimum (3.78) were found in thickness at 120 minutes and 180 minute respectively. At 20-21 0C high mean scores of (3.93) and a low score of (3.76) at 28-29 0C was observed.
Keywords: Temperature; Fermentation period; Quality; Black tea; Total Soluble Solid; Acidity
