The preservation method of tea needs to be flexibly selected according to the type of tea, storage time and environmental conditions. The following are storage recommendations and precautions for different teas:
1. Main factors for tea deterioration
Oxidation: Tea polyphenols, chlorophyll and other ingredients in tea are easily oxidized after contact with oxygen, resulting in loss of aroma and darkening of color.
Humidity: Moisture content exceeding 5% will accelerate mildew, especially non-fermented teas such as green tea and yellow tea are more sensitive.
Odor adsorption: Tea leaves are loose and porous, and are easy to absorb odors in the refrigerator (such as seafood, onion and garlic).
Light and high temperature: Ultraviolet rays will destroy chlorophyll, and high temperature will accelerate oxidation reactions.
2. Recommended storage methods for different teas
1. Green tea, fragrant oolong tea (such as Tieguanyin)
Short-term (1-3 months): Store sealed and away from light at room temperature (need a cool and dry environment, temperature ≤25℃).
Long-term (more than 3 months): It is recommended to refrigerate (0-5℃), divide into small portions and seal them in the refrigerator to avoid condensation caused by repeated use due to temperature difference.
Freezing is not recommended: Freezing (-18℃) can extend the shelf life, but it is easy to produce water vapor due to temperature difference during thawing, which will destroy the structure of tea leaves.
2. Black tea, strong-flavored oolong tea (such as Dahongpao), white tea
Sealed storage at room temperature: The degree of fermentation is high, and the risk of oxidation is low. It only needs to be protected from light and moisture (shelf life is 2-3 years).
Special circumstances: When the humidity is high during the rainy season in the south, it can be refrigerated for a short period of time (strict sealing is required).
3. Black tea (such as Pu'er tea), compressed tea
Stored at room temperature with ventilation: It needs to be in contact with air to promote later transformation, and avoid sealing too tightly (such as wrapping Pu'er tea with cotton paper and putting it in a pottery jar).
Refrigeration/freezing is prohibited: Low temperature will inhibit the activity of microorganisms and block the natural aging process.
4. Flower tea (such as jasmine tea)
Short-term refrigeration: The fragrance of flowers is easy to evaporate, and refrigeration (0-5℃) can delay the loss of fragrance, but it needs to be isolated from other foods.
3. Correct operation of refrigerated/frozen tea
Packaging and sealing:
Packaging in aluminum foil bags or food-grade sealed bags, and sealing after exhausting the air.
Add a layer of plastic wrap or put it in a sealed can to prevent the penetration of refrigerator odor.
Temperature stability:
Refrigerated tea should be placed deep in the refrigerator as much as possible to reduce temperature fluctuations when the door is opened.
When frozen tea needs to be stored for a long time, it can be packaged into single-use quantities at one time to avoid repeated thawing.
Thawing tips:
After taking out the frozen tea, it needs to be placed at room temperature for 2-3 hours in an unopened state, and then opened and used after the temperature is balanced.
4. Common misunderstandings and risks
Misunderstanding: All teas are suitable for freezing
Risk: Freezing will destroy the cell structure of tea leaves, resulting in turbidity and weakened aroma when brewing (especially for tender bud teas such as Biluochun).
Misunderstanding: Put it in the refrigerator directly after opening
Risk: Tea leaves that are not strictly sealed absorb refrigerator odors, and condensation of water vapor is easy to mold.
Misconception: Use glass bottles/transparent bags for storage
Risks: Light accelerates oxidation, green tea tends to turn yellow, and black tea develops a "stale taste".