绿茶低温真空与热风联合干燥新工艺研究

Green Tea Drying Technology of Low-temperature Vacuum Combined with Hot Air

为提高烘干绿茶的品质,特别是保证得到绿茶绿润的干茶色泽,对绿茶的干燥工艺进行了探索。对揉捻后的绿茶采用低温真空与热风联合干燥,以传统的热风干燥和真空冷冻干燥为对照,对不同干燥方法绿茶中叶绿素、茶多酚、氨基酸等有效成分保留程度、绿茶感官品质以及能耗等指标进行综合评价。结果表明:联合干燥工艺绿茶的外形、香气、叶底得分均比传统热风干燥的高,特别是在外形色泽上有明显优势;同时,其综合品质也高于冷冻真空干燥工艺的品质;联合干燥工艺能耗介于热风干燥与冷冻真空干燥之间。

For enhancing the quality of drying green tea, especially guarantee green tea green embellish appearance, the test of following drying process were carried out： using low-temperature vacuum drying combined with hot air to drying green tea after it rolled, take traditional hot air drying and vacuum freeze drying as controls, comprehensive evaluation of the indicators such as chlorophyll, tea-polyphenol, amino acids, effective ingredients preservation degree, green tea sensory quality and energy consumption. The results show that the combined drying technology of green tea got higher score in appearance, aroma and infused leaf than the traditional hot air drying, especially in appearance has obvious advantages in color of dry tea. At the same time, the comprehensive quality is higher than that of frozen vacuum drying process. The energy consumption of combined drying technology lies between hot air drying and freeze vacuum drying.