How to prevent Tea from aging and deteriorating: Do well in preventing pressure, dampness, sealing, avoiding light, and preventing odor. Green Tea is suitable for canning and sealed refrigeration; black tea needs to be stored in a tightly closed and dry container; Oolong tea can be stored at room temperature using double-lid cans such as iron or tin cans; white tea requires a well-sealed tin or iron can for storage; Pu'er tea should be stored with cotton paper in a normal temperature environment without any odor.
How to Better Prevent Tea from Aging?
1. Control of moisture content in tea: The safe moisture limit for tea is below 5%. For coarse tea, if it undergoes one short-term high-temperature Drying, it may not achieve complete and sufficient drying, so two-stage drying is more ideal. Freshly dried tea needs to cool down before being bagged, but this cooling time should not be too long to avoid re-moistening; after the coarse processing, picking out stems and dust, the tea must be dried again to ensure that the moisture content is less than 5%.
2. Avoid light exposure. Experiments have shown that light is the most intense and rapid factor leading to deterioration of tea quality, so freshly made tea should be kept away from light from the refining process until packaging is completed. Additionally, tea merchants and farmers often use transparent plastic bags (PE) for temporary packaging, which should be avoided.
3. Low-temperature storage. Currently, low-temperature preservation is widely recognized as the most effective method for maintaining the original quality of tea. Whether it's color, aroma, or flavor, they can all maintain their best quality under low-temperature storage, especially the freshness of tea. In theory, the lower the temperature for low-temperature storage, the better the preservation effect, and the longer the quality retention time. However, considering economic factors, the temperature should ideally be kept between 0 to 5°C.
4. Oxygen-free packaging. Oxygen is omnipresent, making up over 20% of the atmosphere. The presence of oxygen is closely related to the development of “aging flavor,” “oil flavor,” and changes in color and taste activity during tea storage. Currently, vacuum packaging, nitrogen-filled packaging, and deoxidizer packaging are effective solutions to oxidation during tea storage. Deoxidizers suitable for tea are typically slow-acting inorganic compounds. Deoxidizer packaging requires packaging materials with good gas barrier properties, and aluminum foil bags commonly used for tea are very suitable for this purpose.
How to Store Different Types of Tea to Slow Down Aging
1. Green Tea
Green tea is the type of tea that ages the fastest and deteriorates the most easily, losing its lustrous color and unique aroma very quickly. Since green tea easily absorbs moisture, when the moisture content reaches more than 5%, it will go bad. Even unopened green tea stored for a long time will lose its fragrance, so it should be consumed fresh.
The shelf life at room temperature is about one year, and once opened, it should be transferred into a sealed container and used within a month. The most direct way to store high-quality green tea at home is to refrigerate it, but make sure it's sealed to avoid absorbing other food odors.
2. Black Tea
The moisture content of dried black tea is not high, and it is prone to dampness or loss of aroma. During storage, try to avoid mixing different types of teas. Generally, it can be placed in a tightly sealed and dry container, avoiding light and high temperatures. Storing tea in a tin foil packet or tin can is preferable.
If possible, a purple clay jar or tin can is best, while glass jars should be avoided as sunlight may penetrate them. In summary, avoiding light, heat, and odors allows for longer storage.
3. Oolong Tea
The chlorophyll in Oolong tea reacts to light through photocatalysis, so avoiding light is one of the most important conditions for storing Oolong tea. In addition to avoiding light, preventing moisture is also essential. Oolong tea is semi-fermented, so it doesn't need to be carefully preserved like non-fermented teas; it is relatively easy to store.
If you have a tin can to store tea, that's ideal. If not, you can use an iron can, porcelain can, or a double-lid tin tea can. When filling the can, make sure the tea is packed tightly to reduce oxidation, then seal the lid tightly.
4. White Tea
There are several methods to store white tea:
1. Store white tea in a tea can, with tin or iron cans being preferable, requiring good sealability;
2. Place an appropriate amount of Charcoal in a small cloth Bag and put it at the bottom of the can where the tea is stored. Then, arrange the packaged tea in layers in the can. Seal the mouth of the jar, and replace the charcoal every month;
3. You can also use the three-layer packaging method. Remember that only the same batch of tea can be stored together. First layer: place the white tea or loose tea in an aluminum foil bag, expel the air, and tie it with a rope. Second layer: then put the just-packed white tea in a plastic bag. Third layer: place the white tea in a clean, odorless, and dry cardboard box, and seal it with tape.
5. Pu'er Tea
If stored properly, Pu'er tea becomes more fragrant with age. A widely adopted method is the “Clay Pot Stack-Aging Method”: take a wide-mouthed clay pot and mix old and new teas inside to facilitate aging. For tea cakes that are about to be consumed, disassemble them into loose tea and place them in a clay pot, leaving them undisturbed for half a month before use.
This is because the outer part of a typical tea cake tends to be loose while the center is strong in character. After the above “Tea Aroma Harmonization Method,” the inner and outer parts complement each other, allowing for higher quality tea infusion.