Abstract:

In order to clarify the effect of constant temperature far-infrared technology on the aroma and taste quality of low-value tea in summer and autumn, the sun-dried white tea and stir-fried green tea produced by machine-harvested fresh leaves in summer and autumn in Yuhang District of Hangzhou City were used as initial samples, and the aroma was extracted by far-infrared technology at different temperatures and radiation distances, and the sensory quality and physicochemical components of the treated samples were evaluated. The results showed that the aroma and taste quality scores of sun-dried white tea increased by 1.0 point, the coarse taste disappeared, the aroma was sweeter and the taste was more mellow when the treatment 1(temperature 80 ℃+radiation distance 12 cm) was adopted. The total sensory quality score of stir-fried green tea was the highest under treatment 3 (temperature 120 ℃+radiation distance 15 cm), which increased by 3.2 points compared with the control. The aroma changed from coarse green to sweet, and the taste changed from coarse taste to mellow. Biochemical component analysis showed that the water extract, tea polyphenols, soluble protein and other contents of tea resources in summer and autumn were reduced, and the soluble sugar content of stir-fried green tea was increased after the constant temperature far-infrared aroma extraction technology, which improved the aroma and taste quality defects of low-value tea resources, and had a better flavor quality improvement effect.

Key words: tea in summer and autumn, sun-dried tea, stir-fried tea, sensory quality, biochemical composition