Tea can actually be stored for a long time, but its essence is still agricultural products and has a shelf life. Within the shelf life, the main factors that cause tea deterioration are: First, light. Second, the temperature. Third, the moisture content of tea. Fourth, the air humidity. Fifth, oxygen. Sixth,Microorganisms. Seventh, odor pollution. Therefore, for most teas, the main point of preservation is to avoid light, keep constant temperature, dry, and seal oxygen.

1. Effect of humidity.

The content of chlorophyll in the young shoot leaves is very high, and under light and heat conditions, it is easy to lose green and turn brown. Tea polyphenols are susceptible to oxidation during storage, causing browning. Vitamin c is an important component of tea with nutritional value, and its content is closely related to the quality of tea. Vitamin c is also a substance that is easily oxidized and difficult to preserve. After being oxidized, vitamin c not only reduces the nutritional value of the tea, but also makes the tea brown and loses its freshness.

When the water content in the tea leaves is too low, the tea leaves tend to age and deteriorate. When the amount of sweat in the tea is about 3%, the tea is easy to preserve. When the water content of the tea exceeds 6%, or the air humidity is higher than 60%, the color of the tea becomes brown and dark, and the quality of the tea deteriorates. The water content of the finished tea should be controlled at 3%-6%, and over 6% should be refired and dried.

2. Influence of temperature.

The higher the temperature, the faster the tea ages.

During the storage of tea, the temperature of browning will increase 3 to 5 times each time the temperature rises by 1 ° C. When stored below 10 ° C, the browning of tea can be suppressed. Refrigerating at 20 ° C can almost prevent the aging and deterioration of tea leaves on a regular basis.

3. Effects of oxygen.

If the tea is not stored properly, the oxygen will accelerate the oxidation of the tea and affect the quality of the tea.

4. Effect of light.

Light belongs to energy. Under the light of tea, tea leaves will cause chlorophyll to break down leg color. During the storage of tea, exposure to light will affect the quality and even lose its drinking value.