设3 000、6 000、9 000 lx等3个光强梯度,研究了萎凋光照强度对萎凋叶含水率、容重、柔软性、弹性、塑性、色差等物理特性,以及呼吸特性的影响,并对后续加工叶的物理特性进行了测定。结果表明,随着萎凋进程中鲜叶含水率的逐渐下降,鲜叶容重、柔软性呈先升后降的趋势,在萎凋适度范围内（含水率60%~65%）,以6 000 lx处理最高;弹性呈先下降后增加的趋势,不同处理间以6 000 lx处理的弹性相对较高,塑性变化规律与之相反;色差明亮度L值总体呈下降趋势,红绿度a值呈先下降后增加的趋势,以6 000 lx处理下a值最小,即保绿特性最好,感官审评结果也表明6 000 lx处理的干茶样汤色和外形得分最高,品质最优;CO2释放量总体呈先下降后增加再平稳的变化趋势,3个处理均在萎凋6 h时出现拐点,以6 000 lx处理的释放量最大。
Setting three different withering light intensities, the water content, bulk destiny, flexibility, elasticity, plasticity and color value, the released amount of CO2 of the withering leaves were evaluated, and the effects of different withering light intensity on physical characteristics of rolled leaves, fermented leaves and fired tea were also analysed. The results showed that with the increasing of withering time, moisture content of tea fresh leaves decreased gradually, bulk destiny and elasticity of leaves increased at first and then decreased during withering, and were the highest at 6 000 lx in moderate range (the moisture content was between 60% and 65%), elasticity decreased at first and then increased, the elasticity of tea leaves were relatively highest when the withering light intensity was 6 000 lx, and the variation of plasticity was opposite, the L value (luminosity) declined generally, the “a” value (red and green degree) decreased at first and then increased, and it had the lowest value at 6 000 lx, namely the green keeping was the best, the results of sensory evaluation also showed that the liquor color and shape of black tea at 6 000 lx had the highest score, with the best quality, the released amount of CO2 decreased at first, then increased and was stable finally, the urning point occurred during withering at 6 h, and the amount was the largest when the withering light intensity was 6 000 lx.
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