Pu'er tea values its vintage, and many enthusiasts are passionate about collecting and drinking aged teas. When it comes to the vintage of Pu'er tea, storage is a natural topic of discussion. Besides raw materials and processing techniques, proper storage is crucial in determining the quality of Pu'er tea, ensuring it improves with age.
Some tea merchants can establish professional facilities to store Pu'er tea, controlling factors such as Humidity and temperature to ensure optimal aging conditions. However, for most merchants and enthusiasts, such professional storage is not feasible, and they must rely on natural conditions. Under these circumstances, the transformation and quality of Pu'er tea are largely determined by the natural climate.
Natural storage of Pu'er tea essentially means dry storage. By “dry storage,” we mean a clean and relatively dry environment. Cleanliness is the priority, with moderate dryness! The aging process of Pu'er tea requires both humidity and temperature. Extensive practice and scientific research have shown that the transformation of Pu'er tea involves enzymatic reactions and microbial Fermentation, leading to changes in taste. Microorganisms, referred to as beneficial bacteria, play a key role in this transformation. These beneficial bacteria and enzymatic reactions thrive best at temperatures around 20°C to 30°C and humidity levels between 60% and 70%.
The three most popular locations for storing Pu'er tea are Guangzhou, Kunming, and Menghai. These places have significantly different climates, resulting in distinct transformations and qualities in the stored teas. Today, we will focus on the advantages and disadvantages of storing Pu'er tea in Kunming.
Kunming, known as the “Spring City,” is located on the Yunnan-Guizhou Plateau, where the temperature varies little throughout the year. It is a high-altitude, humid city with relatively dry air during Winter and spring. According to macro data, the average annual temperature is 15 degrees Celsius, and the humidity is 71%, only 8 percentage points lower than in Guangzhou. However, Kunming cannot be classified as a humid climate; despite having considerable humidity, the evaporation rate is higher, making it relatively dry.
The transformation of Pu'er tea relies on fermentation, which requires temperature and humidity. Kunming's climate, being relatively dry with low air humidity and minimal temperature fluctuations, provides an ideal range for Pu'er fermentation. During aging, enzymatic reactions involving oxidation enzymes dominate, resulting in a relatively pure and singular transformation. Although the aging process takes longer, the transformation led by oxidation enzymes within the tea ensures more stable results with strong predictability in terms of quality. This approach minimizes the risk of mold or degradation, reducing potential losses to the tea.
The most prominent feature of Kunming's dry storage is a strong aged fragrance with virtually no storage odor.
First, aroma: The aroma undergoes noticeable changes, often developing honey-like notes. However, undesirable aromas such as smoky, burnt, or musty smells are harder to eliminate.
Second, liquor color: There are minimal changes in liquor color during the first two years. Afterward, it becomes distinctly clear yellow, usually lacking transparency and richness. When cooled, the clear yellow liquor oxidizes into a clear red hue. Older teas may exhibit amber tones, while younger Bud teas are more likely to turn clear red.
Third, flavor: The initial years are characterized by intense flavors, with bitterness and astringency dissipating slowly. The flavors are distinct but uncomfortable, with sweetness notably inferior to that achieved through humid storage. Over time, the tea becomes milder, and after 3-5 years, a plum-like acidity appears, indicating the tea has reached a drinkable stage.
Fourth, leaf base: Changes in the leaf base are not obvious during the first two years, with green tones and red or yellow pieces from the initial processing being evident. After around three years, the leaf base turns yellowish with light green hues, and the red pieces blend into the overall color. As the years pass, the leaf base colors gradually become uniform.