How to Fix the Green Leaves of Chrysanthemum Tea Before Drying

During the processing of chrysanthemum tea, mechanical fixing is first performed. This can be done by steam or microwave.

Steam fixing utilizes high temperatures to inactivate the polyphenol oxidase enzyme in fresh chrysanthemums, while also causing them to lose some moisture and soften. The resulting chrysanthemum tea treated with high-temperature steam fixing has a vibrant color.

During steam fixing, the temperature must be maintained above 100°C. A single processing line can process 4,000-5,000 kg of fresh chrysanthemums in one hour, with a steam fixing time of 1-2 minutes. This shorter time allows for the evaporation of water, releasing the low-boiling-point aromatic compounds in the fresh chrysanthemums, releasing their delicate fragrance without excessively evaporating the aromatic oils.

During microwave killing, fresh chrysanthemums are evenly placed on the conveyor belt of the microwave killing line, overlapping by 2-3 times. Then, the conveying speed is determined according to the processing power of the microwave line for killing. Microwave killing can quickly raise the temperature to the passivation temperature of fresh chrysanthemum polyphenol oxidase, which is between 60-80 degrees Celsius in a short period of time, effectively reducing the volatilization of low-boiling point aromatic oil substances in the chrysanthemum product. The microwave killing time is generally 2-3 minutes. After the killing is completed, it can be dried.