丹参叶绿茶的保质干燥技术研究

Research on Quality Preservation Drying Technology of Salvia Leaves Green Tea

为了发展丹参叶绿茶产品,本文研究了不同干燥方法对丹参叶有效成分的影响。以丹酚酸B和叶绿素含量等指标确定了热风干燥和真空冷冻干燥的最佳工艺参数,并与丹参叶中的有效成分进行比较。最终确定的热风干燥的最佳工艺参数为温度60℃,风速0.6 m/s,物料厚度为2层。真空冷冻干燥的最佳工艺参数为采用-25℃进行预冻,保持2 h左右的时间,50 Pa升华22 h左右,20℃解析14 h。结果表明真空冷冻干燥是丹参叶绿茶保质干燥的最佳方法,其对丹参叶中的丹酚酸B和叶绿素含量保留率分别为98.76%和82.21%。

In order to develop Salvia leaf green tea products, the effects of different drying methods on effective components of Salvia leaves were studied in this paper. The optimum technology parameters for hot-air drying and vacuum-freeze drying were obtained by taking Salvianolic acid B and chlorophyll content as indexes, and comparing with the effective ingredients of Salvia leaves. The results showed that the optimal parameters were temperature 60℃, wind speed 0.6 m/s, and material thickness 2 layers for hot-air drying. The optimum processing for vacuum-freeze drying were pre-freezing for 2 h under -25℃, and kept on -25℃, 50 Pa sublimation for 22 h, then 20℃ resolution for 14 h. Experiments showed that vacuum-freeze drying was the best quality preservation method, and the preservation for Salvianolic acid B and chlorophyll were 98.76% and 82.21% respectively under these optimal parameters.