Abstract
The color of made tea is one of the most important factors for evaluating tea cultivars or lines. In the present study, we investigated the relationship between the sensory test score of color and the measured color space unit of hue angle (h*), pigments, and pH value for objective evaluation of line selection. The experimental results showed that the sensory test score of color had a significant correlation with the measured color space unit of h* value and the conversion rate of chlorophyll into pheophytin. The pH value of made tea also had a positive correlation with the sensory test score, because a lower pH would induce a higher pheophytin conversion rate. Although the h* value of fresh tea leaves had a high correlation with that of made tea in the first tea crop season, a low correlation was found with the second tea crop. Thus, there may not be a matching relationship between the color of fresh tea leaves and that of processed tea leaves.
In conclusion, measurement of the h* value, conversion rate of chlorophyll into pheophytin, and pH value would be useful in the evaluation of tea cultivars and lines.
