Tea has a strong tendency to absorb moisture and odors from the air, making it susceptible to losing its flavor and aroma if not stored properly. The more delicate and highly fragrant the tea, the harder it is to preserve. Over time, tea can change in fragrance, taste, and color, losing its fresh quality and developing an aged taste. Therefore, understanding how to store tea correctly to maintain its quality is essential in daily life.

1. The main factors that cause deterioration in tea include:

I. Light.

II. Temperature.

III. Moisture content of the tea.

IV. Atmospheric humidity.

V. Oxygen.

VI. Microorganisms.

VII. Contamination by foreign odors.

The deterioration caused by microorganisms is influenced by temperature, moisture, and oxygen levels, while odor contamination is related to the storage environment. To prevent the degradation of tea, control must be exerted over light, temperature, moisture, and oxygen. Packaging materials should be able to block light, such as metal cans or aluminum-lined bags. Oxygen can be removed through vacuum sealing or nitrogen flushing, or by using desiccants. There are two main methods of tea storage based on the temperature: room temperature storage and cold storage. Regardless of the method used, the relative humidity of the storage space should ideally be kept below 50%, and the moisture content of the tea during storage should be maintained at less than 5%.

2. Why is Storing Tea Important?

To store tea effectively, it's important to understand both the ‘how' and the ‘why', which will help you make informed decisions and improve your knowledge as a tea connoisseur.

Moisture causes the tea to become damp.

Due to its porous nature and hygroscopic properties, tea absorbs moisture easily. If the tea crumbles easily when pressed, it indicates that it is relatively dry. If it feels slightly soft, attention should be paid.

Air causes oxidation in tea.

Many active compounds in tea are prone to oxidation, especially polyphenols and vitamin C. Exposure to oxygen can cause green teas to turn yellow and black teas to turn brown, diminishing their freshness and aroma.

Light causes discoloration in tea.

Tea is sensitive to light, particularly chlorophyll, which can break down under light exposure, causing the tea to darken and turn brown. Some fatty substances in tea can also oxidize when exposed to light, leading to the development of stale flavors.

High temperatures cause the tea to spoil.

Exposure to high temperatures can alter the color and taste of tea. Temperature significantly affects the rate of oxidation reactions in tea. Studies have shown that for every 10°C increase in temperature, the rate of browning in dry tea and tea infusion accelerates three to five times.

Foreign odors cause the tea to develop off-flavors.

Due to its porous structure, tea not only absorbs moisture and oxygen but also easily picks up foreign odors. This includes odors from the environment and packaging materials.

3. Different Storage Methods for the Six Main Types of Tea

Green Tea

To preserve the freshness and aroma of green tea or lightly oxidized oolong teas like Tieguanyin, they can be stored in the refrigerator with a temperature range of approximately 0°C to 5°C. By altering the environmental temperature, the oxidation rate of the chemical components in the tea is reduced, thereby slowing down the aging and deterioration process.

Yellow Tea

Yellow tea is similar to green tea in terms of storage. It can be sealed and placed in the refrigerator (ideally at around 5°C) and should be stored separately from other foods to avoid absorbing their odors.

Black Tea (Red Tea)

Black tea is prone to moisture absorption and loss of aroma, so it is best to avoid mixing different types of tea. It can be stored in sealed containers like cans, tea bags, or thermoses. Before placing the tea in these containers, it is recommended to use a plastic bag to package the tea and remove as much air as possible, then seal it tightly to retain the tea's aroma.

Oolong Tea (Blue Tea)

Oolong tea places a great emphasis on aroma, so care should be taken to minimize the loss of fragrance during storage. When filling containers, leave minimal empty space to reduce the dispersion of aroma. Oolong tea, being a partially fermented tea, is relatively easy to store. Ceramic jars, metal cans, and tea bags are suitable options for storage, but tin cans are ideal. When filling the container, ensure that the tea is packed tightly to minimize oxidation and then seal it securely.

White Tea

White tea can be stored long-term under suitable conditions and, if properly preserved, many compressed white teas improve with age. Compressed teas can be stored in a dry place with moderate air circulation and no foreign odors. A popular method is the “Terracotta Pot Maturation Method,” which involves placing a mix of old and new tea in a wide-mouthed terracotta pot to promote aging. For cakes of tea intended for consumption soon, they can be broken into loose leaves and placed in a jar for about half a month before use. This method helps to harmonize the flavors within the cake, as the outer layers tend to be looser and more permeable, while the center has a stronger character. After this “tea essence balancing method,” the tea can achieve better quality and taste.

Pu'er Tea (Dark Tea)

Pu'er tea requires ventilation, dryness, and freedom from foreign odors for proper storage. It is best stored at room temperature. Maintaining ventilation and dryness is crucial when storing Pu'er tea. Avoid using plastic bags for storage! Instead, use materials like kraft paper or traditional paper that allow some air circulation. If storing a larger quantity, you can place a certain amount of activated charcoal nearby to absorb moisture and odors.