Tea making is one of the Chinese traditional industries. To improve the quality of tea and realize the modernization of the tea-making industry, it is necessary to apply the new techniques–microwave techniques in the initial processing and deep-processing of tea making industry.
At present, microwave techniques are mainly used in water removing, drying and insects preventing, sterilization and extraction process. And the following are how microwave applies in these processes.
1. Application of Microwave Technology in Water-removing Process of Tea Making
Since there is moisture in tea leaves when manufacture green tea and oolong tea, the water removing process is necessary. When using the microwave to remove the water, the moisture in tea leaves was polarized in microwave magnetic field and had dipole features, the moisture changed its polarity direction with the magnetic field, the molecule vibrated in high speed which generated friction heat and the heat rose from the internal of the tea leaves. Using this character of the microwave, it can make the tea leaves heating up in a short time and reach the critical point temperature of the enzymatic inactivation to accelerate the removing of the water in tea.
2. Application of Microwave in Drying Process of Tea Making
The traditional hot air drying through an external heating process to dry the tea leaf which makes the tea leaves dried on the surface but still has water internally, while microwave drying heat the tea leaves from inside to outside which will make the tea leaf dry thoroughly and uniformly. Microwave drying in tea making will not only improve the drying process but also improve the quality of the tea leaves. And through microwave drying, the tea leaf keeps fresh and green.
3. Microwave Techniques Applied in Insects Preventing and Mildew Proofing Process
Since many insects will be generated in the process of storing and transportation, it is very important to take measures to keep the tea leaf away from insects and mildew. Differently from the methods of medicine fumigant, microwave technology can kill the insects and prevent mildew through lowering the moisture content which has no drug residue problems.
4. Application of Microwave Techniques in the Extraction of Tea Juice
The process of tea soft drinks is closely related to the extraction process. The conventional method of extraction of the tea-making industry is hot water extraction and microwave extraction now is gradually applied in this field. The process of extraction is to put some tea leaves in the extractor first, then put enough water into the extractor, and heat the extractor in the required temperature and time, finally get the tea juice through filtration. Microwave extraction needs less time and the extraction rate is higher than that of using the conventional method.
Microwave technique with the remarkable advantages of fast heating, uniform drying, and high efficiency, has broad application in the tea-making industry, Thus it’s obvious the best choice for tea leaves processing.
