南北两地气候差异对白茶萎凋效果和品质的影响

Influence of Climate Difference between the North and the South of China on the Withering Effect and Quality of White Tea

文章以福鼎大白为原料,于早春在泰安和福鼎两地分别采用室内萎凋和复式萎凋两种传统工艺加工白茶,测定其萎凋过程中的环境因子和鲜叶、成茶品质理化指标,并审评成茶感官品质。结果表明:(1)早春首批白茶加工时,泰安的平均温度高于福鼎,而平均湿度和平均光照强度低于福鼎;白茶萎凋时其萎凋叶的减重速率升高快于福鼎,萎凋时间仅需17 h,显著短于福鼎的52 h;(2)与福鼎相比,泰安早春首批鲜叶的芽叶外形细长、茸毫少;品质生化成分咖啡碱、可溶性糖含量低,但茶多酚、可溶性蛋白含量高;成茶中可溶性蛋白和可溶性糖含量与鲜叶情况一致,其它主要理化指标差异不显著;成茶感官品质外形、叶底得分低,而滋味、香气稍偏青;(3)在泰安气候条件下加工白茶,需采取适度增湿、厚摊等措施延长萎凋时间,避免品质偏青。

Fuding dabai was used as raw material in early spring and processed by two traditional withering techniques(indoor withering and multiple withering)in Taian and Fuding city.The environmental factors during the withering were measured and the chemical components and sensory evaluation of fresh leaves and processed tea were analyzed.The results showed that:(1)When the first batch of white tea was processed in early spring,the average temperature of Taian was higher than that of Fuding and the average humidity and light intensity of was lower than that of Fuding.During the withering,the weight loss rate of the withered leaves in Taian increased faster than that of Fuding.The withering time was only 17 h,which was significantly shorter than Fuding’s 52 h.(2)Compared with Fuding,the first batch of fresh leaves of Taian had slender shape and few fuzz,the chemical components were low in caffeine and soluble sugars,and high in polyphenols and soluble proteins.The content of soluble proteins and sugars in processed white tea was consistent with that of fresh leaves,while other chemical components had no significant difference.The processed white tea had lower score of sensory evaluation in appearance and infused leaf,while taste and aroma with grass flavor.(3)Moisturizing,thickening and other measures were necessary to prolong the withering time and avoid grass flavor during the white process under the Taian climatic conditions.