Tea leaves are highly hygroscopic and absorb odors easily; they readily absorb moisture and foreign odors from the air. If stored improperly, even slightly, they will lose their flavor within a short period of time. Moreover, the more lightly fermented and highly aromatic the tea is, the more difficult it is to preserve.
Generally, after tea has been stored for a period of time, its aroma, flavor, and color will change; the freshness of the original tea will fade, and a stale taste will gradually emerge. Therefore, mastering proper tea storage methods to ensure its quality is essential in daily life.
The main factors causing tea deterioration are: 1. Light. 2. Temperature. 3. Moisture content of the tea. 4. Atmospheric humidity. 5. Oxygen. 6. Microorganisms. 7. Off-flavor contamination. Among these, deterioration caused by microorganisms is influenced by factors such as temperature, moisture, and oxygen, while off-flavor contamination is related to the storage environment.
The primary environmental factors affecting the deterioration and aging of tea leaves are temperature, moisture, oxygen, light, and their interactions.
● Temperature: The higher the temperature, the more likely the tea leaves are to turn brown; low-temperature refrigeration (or freezing) can effectively slow down browning and aging.
● Moisture: When the moisture content in tea leaves exceeds 7%, it accelerates quality deterioration and causes the color of the tea leaves to change.
● Oxygen: The oxidation of various substances that cause tea deterioration is related to the presence of oxygen.
● Light: Exposure to light has an adverse effect on tea; it accelerates various chemical reactions within the tea, and chlorophyll tends to fade when exposed to light.
