[关键词]
[摘要]
为提高夏季日照绿茶的整体品质,采用循环滚炒(加工30 min)和茶叶复干技术(加工30 min、60 min和90 min)对夏季日照绿茶进行干燥,分别从感官审评、主要品质成分以及香气组成等方面对茶叶品质变化进行对比分析。结果表明,不同炒干条件下的夏季日照绿茶品质差异明显,其中采用茶叶复干技术加工30 min后的绿茶外形更紧结、色泽更润、汤色更绿,滋味无明显水闷气;茶叶中的内含物质保留量更高(水浸出物、茶多酚、游离氨基酸含量分别是44.70%、16.00%、2.20%),且对叶绿素总量(0.27%)破坏程度低,具有高火香气的杂环化合物相对含量(1.61%)大幅减少。4种炒干处理的夏季日照绿茶被检测到38种共有香气成分,茶叶复干技术加工30 min的绿茶香气组分以酯类为主,其他3种炒制条件下的绿茶则以酸类为主。因此,在130 ℃的温度条件下,采用茶叶复干技术加工30 min,可有效解决传统夏季日照绿茶存在的色香味形欠佳的品质问题。本研究结果为茶叶复干技术在日照绿茶加工中的应用提供了理论依据。
[Key word]
[Abstract]
In order to improve the overall quality of Rizhao green tea harvested in summer, the sensory evaluation, changes of main quality components and aroma components of Rizhao green tea harvested in summer dried by the technology of circular roll-roasting (processing for 30 minutes) and tea re-drying (processing for 30 minutes, 60 minutes and 90 minutes) were analyzed. The results showed that the quality characteristics of Rizhao green tea harvested in summer dried by different roasting methods were obvious different. The quality of green tea dried by re-drying technology (processing for 30 minutes) was better than other three roasting methods, with the tighter shape, the more moist color, the greener soup, no obvious water tightness taste; the higher retention of the contents (water extracts, tea polyphenols and free amino acids were 44.70%, 16.00% and 2.20%, respectively), the lower damage to the total amount of chlorophyll (0.27%), the significant reduction of heterocyclic compounds with high-fire aroma. Thirty-eight identical aroma components were detected in 4 kinds of Rizhao green tea dried by different methods. The main aroma components of green tea processed by there-drying technology for 30 minutes were esters, while the other three kinds of green tea were acids. Therefore, the problem of poor quality of traditional summer green tea could be effectively solved using the tea re-drying technology for 30 minutes at 130 ℃. The results of this work can provide theoretical basis for the application of there-drying technology in the processing of Rizhao Green Tea.
[中图分类号]
[基金项目]
浙江省重点研发计划项目(2017C02007)