光照强度对发酵叶主要生化成分动态变化的影响

摘要

By using two leaves and a bud shoot of Fuding Dabai as fresh leaves material, the dynamic effects of six different fermenting light intensities (0 lx, 3000 lx, 6000 lx, 9000 lx, 12000 lx and 15000 lx) on major biochemical components of tea fermented leaves were studied. Tea samples were collected every 30 min and the contents of tea polyphenols, flavonoids, total amino acids, soluble protein, soluble sugar, catechin compositions, theaflavins and amino acids were detected. The results showed that with the increasing of fermentation time, the contents of tea polyphenols and catechins compositions decreased gradually. The contents of flavonoids, total amino acids and soluble sugar showed opposite trends. Both the soluble protein and theaflavins components increased at first and then dropped, with its peak at around 120 min. Comparing different light intensity processings, 15000 lx strong light treatment significantly decreased the contents of tea polyphenols, catechins compositions, the accumulation of flavonoids and the amino acid compositions. The highest contents of soluble protein and soluble sugar were identified in samples under 9000 lx light treatment. While, the highest contents of theaflavins components and theanine were found in samples under 3000 lx light treatment. The sensory evaluation also showed that the liquor color and taste of samples under 3000 lx light treatment got the highest score, indicating a good quality.%以福鼎大白茶一芽二叶鲜叶为原料,设置0 lx、3000 lx、6000 lx、9000 lx、12000 lx、15000 lx等6个光照强度处理,研究不同光照强度对发酵叶主要生化成分的动态变化规律的影响.在发酵过程中,每隔30 min取样,测定茶多酚、黄酮、氨基酸、可溶性蛋白质、可溶性糖、儿茶素组分、氨基酸组分和茶黄素组分等含量.结果表明,随着发酵时间的延长,不同光照处理样茶多酚、儿茶素总量均呈现下降的趋势,黄酮、游离氨基酸和可溶性糖呈现上升的趋势,可溶性蛋白质总量和茶黄素总量呈现先升后降的趋势,拐点在发酵120 min左右.不同光照强度处理间比较,15000 lx强光照处理会促进茶多酚和儿茶素组分含量的下降及黄酮、游离氨基酸总量的积累;9000 lx处理样的可溶性蛋白质和可溶性糖含量最高;3000 lx处理样的茶黄素组分总量和茶氨酸比重最高;感官审评结果表明3000 lx处理样的汤色、滋味等得分最高,品质最优.