关键词: 抹茶, 香味阈值, 感官审评, 成分测定分析

Abstract:

The quality of samples of 6 matchas and 3 tenchas was analyzed by sensory evaluation and the chemical
composition was evaluated by conventional assays and amino acid analysis. The results showed that the particle size of
6 kinds of matcha ranged from 75 μm to 1.6 μm, reaching ultrafine powder level. The sensory evaluation scores were
(85.90±1.44)–(96.90±1.26), according with the sensory quality standard of matcha. The flavor threshold values ranged
from 1 500 to 2 500. A wide variety of components were detected in matcha samples in abundant quantities, and the amount
of water extracts was high, being averaged at 35.63%. The taste of matcha was described as highly refreshing and the
total content of free amino acids was relatively high with an average value of 7.20%. In total, 18 amino acids in matcha
were detected, including 7 ones more than 1 000 mg/kg, such as theanine, glutamate and others. The color of matcha
was verdure due to the abundance of total chlorophyll (averaged at 0.85%). Moreover, the ratio of chlorophyll a to
chlorophyll b (CHLa:CHLb) was high and ranged from (1.12±0.13) to (1.49±0.17). The texture of matcha samples was
fine and the crude fiber content was low with an average value of 8.70%. Compared with Japanese matcha products, the
quality of Chinese matcha products still needs to be improved. Further investigations with respect to ecological environment
of tea garden, species, cultivation, picking and control management in matcha production are needed to improve the quality
of Chinese matcha products.

Key words: matcha, threshold of flavor, sensory evaluation, compositional analysis