For a long time, hot air drying is the main way tea dry.
In recent years, with freeze-drying technology applied to the rapid development of tea in the drying process.
Tea vacuum freeze drier (
The tea lyophilizer for short)
Preparation of freeze-drying tea is not only need to remove the moisture is advantageous to the long-term storage, more flavor had important effect on the formation of the quality of tea.
The study found that in the process of drying, some of the tea insoluble matter cracking and isomerization, to improve the taste and with the development of pure fragrance has a very good quality, and the effect.
with oolong tea as the example below, tell me about the influence of the quality of tea tea freeze drying machine:
traditional oolong tea early drying with hot air drying.
Existing research shows that the low temperature hot air drying processing (
55℃）
Can make the linalool and its oxides (
我,(二)
, methyl salicylate, geraniol etc. Content increased;
After high temperature roasting,
110℃）
After hexanal, nerolidol, indole content reduce, limonene, (
Shun)
-
3, 7 -
Dimethyl -
1,3,6 -
Zinn triene, linalool and its oxides (
我,(二)
α;
-
Terpineol compounds content, etc.
In the process of hot air drying, such as hydrolysis, oxidation reaction, the chlorophyll in leaves and flower aroma substances more losses, adverse to the qing scent oolong tea quality.
to do so, the researchers tea vacuum freeze drying machine was applied to qing scent oolong tea processing, the experimental results showed that the vacuum freeze drying of qing scent oolong tea fragrant noble, flower show, tang yellow green and bright, taste mellow back to gan, its quality is significantly higher than hot air drying on, so that the vacuum freeze drying is more advantageous to fully display the qing scent of oolong tea & other;
Color & throughout;
、“
Sweet & throughout;
、“
Flavor & throughout;
。
In addition, the linalool in freeze-dried oolong tea, orange ene, & beta;
-
Caryophyllene, isovaleric acid ethyl benzene, & beta;
-
Cadinene, nerolidol, method of alcohol content is higher than the hot air drying tea.
Ya-hui huang will vacuum freezing dryer applications such as guangdong single clump of drying process, also shows that the vacuum freeze drying of single plexus tea quality is improved;
Of vacuum freeze drying technology exploration show that the first preliminary baking again the optimal quality of vacuum freeze drying processing of tea, but without baking directly by vacuum freeze drying processing poor quality tea samples.
Yu-fang liu description for low temperature vacuum drying technologies such as the impact on the quality of oolong tea, the results show that by using this method to make oolong tea appearance color green, bright yellow green aroma fresh lovely rich, rinsing, taste mellow fragrance, comprehensive quality is higher than the traditional hot air drying products, and less than the energy consumption of vacuum freeze drying, low-temperature vacuum drying time is short, is a new drying method can improve the quality of oolong tea.
