变温滚炒与高温足干提香结合对秋季炒青绿茶品质的影响

Effect of Combination of Variable Temperature Roll-roasting and High Temperature Final Drying Fragrance-enhancing on the Quality of Autumn Roasted Green Tea

为充分利用秋茶鲜叶资源,以一芽三叶(部分一芽二叶)鲜叶为原料,采取变温滚炒与高温足干提香结合工艺加工炒青绿茶,分别对茶样香气与内含品质成分进行检测分析并结合感官审评。结果表明香气以变温滚炒(前期温度260℃、时间15 min,后期温度220℃、时间25 min)与高温足干提香(105℃、60 min)组合工艺最佳,栗香高锐、持久,滋味浓强、回甘,感官评分最高(91.10分);香气组成为醇类含量36.38%、碳氢类23.43%、杂环化合物12.50%、酯类10.08%、醛类6.30%、酮类5.44%、酸类4.64%及含硫化合物1.24%。变温滚炒处理的醇类和醛类相对含量比恒温滚炒的高33.52%,变温滚炒与高温足干提香结合处理的醇类和醛类相对含量最高。此外,变温滚炒处理的脱氢芳樟醇含量比恒温滚炒的高609.60%。其他内含品质成分方面,变温滚炒与高温足干提香组合处理茶样的茶多酚、咖啡碱含量较恒温滚炒和相对低温足干提香处理的高,酚氨比值较大(5.59),茶滋味较浓强;儿茶素总量及EGCG含量与对照等处理更高,滋味的收敛性更强,回甘更明显。

In order to make full use of the fresh tea leaf resources of autumn tea,using fresh leaves with one bud and three leaves(some with one bud and two leaves) as raw materials,roasted green tea was processed by adopting the combination process of variable temperature roll-roasting and high temperature final drying fragrance-enhancing.The aroma and quality components of the tea samples were detected and analyzed,and sensory evaluation was combined.The results showed that the combination process of variable temperature roll-rosting(initial temperature 260℃ for 15 minutes,later temperature 220℃ for 25 minutes) and high-temperature final drying fragrance-enhancing(105℃,60 minutes) was the best for aroma,with high and long-lasting chestnut aroma,strong and sweet taste,the sensory score was the highest(91.10points);The aroma composition was alcohols of 36.38%,hydrocarbons of 23.43%,heterocyclic compounds of 12.50%,esters of 10.08%,aldehydes of 6.30%,ketones of 5.44%,acids of 4.64%,and sulfur compounds of 1.24%.Among them,the relative content of alcohols and aldehydes in the variable temperature roll-roasting treatment is 33.52% higher than that in the constant temperature roll-roasing treatment,and the relative content of alcohols and aldehydes in the combination of variable temperature roll-roasting and high temperature final drying fragrance-enhancing treatment is the highest.In addition,the dehydrolinalool content in the variable temperature roll-roasting treatment is 609.60% higher than that in the constant temperature roll-roasting treatment.In terms of other quality components,the combination of variable temperature roll-roasting and high temperature final drying fragrance-enhancing treatment has a higher content of polyphenols and caffeine in tea samples compared to constant temperature roll-roasting and relatively low temperature final drying fragrance-enhancing treatment,with higher phenol ammonia ratio(5.59),and stronger tea taste;The total amount of catechins and EGCG content were higher than those of the control treatment,with stronger astringent taste,and sweeter aftertaste.