Tea should be stored in a dry and ventilated place, not in damp, high-temperature, unclean, or sun-exposed areas. Additionally, there should be no strongly scented items such as camphor, medicine, or cosmetics nearby. Experts also remind everyone that different types and grades of tea should not be stored together. Do not use quicklime as a desiccant when storing black tea or scented tea.

Environmental Factors Affecting Tea Deterioration

The main environmental conditions affecting tea deterioration and aging are temperature, moisture, oxygen, light, and their interactions.

Temperature

Higher temperatures cause the appearance and color of tea to turn brown more easily. Low-temperature refrigeration (freezing) can effectively slow down the browning and aging of tea.

Moisture

When the moisture content in tea exceeds 5%, it accelerates the deterioration of tea quality and promotes the oxidation of residual enzymes in the tea, leading to color changes.

Oxygen

The oxidation of various substances that cause tea deterioration is related to the presence of oxygen.

Light

Light exposure has adverse effects on tea, accelerating various chemical reactions. Chlorophyll easily fades when exposed to light.

From the above, it can be concluded that:

Reducing the storage environment temperature.

Minimizing contact between tea and oxygen.

Blocking tea from exposure to oxygen.

Preventing direct light exposure can all slow down tea deterioration.

Tea Storage Methods

Generally, tea purchased by households is either canned or loose tea. Since it is not consumed all at once, storage becomes an issue. Below are several commonly used household tea storage methods:

Plastic Bag and Aluminum Foil Bag Storage Method

It is best to choose food-grade plastic bags with seals, preferably those made of thick, high-density materials. Avoid using scented or recycled plastic bags. After filling the bag with tea, squeeze out as much air as possible. Using a second plastic bag to cover it in reverse is even better. Transparent plastic bags should not be exposed to sunlight. The principle of using aluminum foil bags is similar to that of plastic bags. Additionally, divide the purchased tea into small packages, seal them, and store them in the refrigerator. Brew in batches to reduce exposure to air after opening and delay quality deterioration.

Metal Can Storage Method

You can use iron cans, stainless steel cans, or tightly sealed tin cans. If the can is new or has been used to store other items with odors, place a small amount of tea leaves in the can, cover it, and shake it gently to rub the inner walls. Then discard the leaves to remove odors. Two-lidded stainless steel tea cans available on the market are convenient and practical. If you place the tea in a clean, odorless plastic bag before putting it in the can and seal the lid with tape, it is even better. Metal cans containing tea should be placed in a cool place, away from direct sunlight, odors, dampness, and heat sources. This prevents the iron can from rusting and slows down the aging and deterioration of the tea. Tin cans, with their dense material, are particularly effective in preventing moisture, oxidation, light, and odors.

Low-Temperature Storage Method

Keep the tea storage environment below 5 degrees Celsius, i.e., use a refrigerator or freezer to store tea. When using this method, note the following:

For storage periods within six months, maintaining a temperature of 0–5 degrees Celsius is the most economical and effective. For storage exceeding six months, freezing (-10 to -18 degrees Celsius) is better.

It is best to use a dedicated refrigerator (freezer) for storage. If you must share the refrigerator (freezer) with other food items, the tea should be properly packaged and completely sealed to avoid absorbing odors.

Ensure good air circulation in the refrigerator (freezer) to achieve cooling效果.

When purchasing tea in large quantities, divide it into small packages (cans) first before placing them in the refrigerator (freezer). Each time, take out only the amount needed for brewing. Avoid repeatedly freezing and thawing the same package of tea.

When taking tea out of the refrigerator (freezer), allow the tea in the can to return to room temperature before opening it. Otherwise, suddenly opening the can may cause moisture to condense on the tea, increasing its water content and accelerating the deterioration of the remaining tea.

Long-Term Tea Storage Treatment Methods

To store tea for extended periods, the moisture content should be controlled between 3-5%. The degree of roasting and drying is crucial to the tea's storage life. Generally, heavily roasted tea with lower moisture content can be stored longer.

When the optimal storage period for tea is reached, it should be taken out and re-roasted. You can clean an electric rice cooker until odor-free, dry it, and then place the tea on a ceramic plate or aluminum foil inside the cooker. Set the switch to the [Keep Warm] position, half-cover the lid, and stir occasionally. After about half a day, the tea will transform from a stale odor to a clean, ripe aroma. It is ready when pinched between thumb and forefinger, it crumbles easily. After cooling, it can be repackaged and stored again.

Some people use microwave ovens to dry and roast tea. However, due to the short heating time and difficulty in controlling the process (often with the door closed), it can lead to surface charring or failure to remove stale odors. This method still requires technical improvements.

The safest method is to entrust珍藏 tea to a familiar tea master or tea farmer for re-roasting.