Pu'er tea is unique among teas in that it improves with age, becoming richer and more fragrant over time. When stored properly within a reasonable timeframe, the flavor of Pu'er tea deepens and matures. There are two types of Pu'er: raw (sheng) and ripe (shou). Each has its own distinct taste, with some preferring the pure Sweetness of raw Pu'er and others the rich depth of ripe Pu'er. Without considering taste differences, which type is better for long-term storage? Let's explore this question.
Long-Term Storage of Pu'er: Raw Teas Have Greater Potential for Transformation
The most significant difference between raw and ripe Pu'er lies in their production processes. Compared to raw Pu'er, ripe Pu'er undergoes an additional step known as wet-piling Fermentation. Although this step involves simply adding Water and allowing the tea to ferment, it triggers complex biochemical changes through enzymatic reactions, microbial fermentation, and moist heat effects.
During these three processes, the chemical composition of the tea changes rapidly, transforming the internal substances of the Pu'er. The higher the degree of fermentation, the greater the transformation of internal substances during the wet-piling process. This means there is less material available for further transformation later on, significantly limiting the potential for change during long-term storage.
Long-Term Storage of Pu'er: Raw Teas Develop More Complex Flavors
In the case of ripe Pu'er, the wet-piling process, along with microbial fermentation and enzymatic reactions, generates heat. Combined with the inherent moist heat effect, this kills off many microorganisms and largely destroys the enzymes present in the tea leaves. As a result, the amount of oxidizing enzymes and microorganisms available for subsequent transformations during storage is greatly reduced.
Consequently, the main changes in ripe Pu'er during long-term storage involve alterations in its nature (from hot after fermentation to milder after storage), the dissipation of the wet-pile aroma, and transformations in aromatic compounds that affect the tea's scent. In terms of taste, ripe Pu'er tends to remain relatively stable during long-term storage.
On the other hand, the transformations in raw Pu'er during long-term storage are primarily driven by oxidizing enzymes, aided by microorganisms and natural slow oxidation. Since raw Pu'er does not undergo the intense short-term fermentation that ripe Pu'er does, it retains a richer store of internal substances. This allows more materials to participate in the transformation process, resulting in a wider range of flavors and aromas during long-term storage.
Long-Term Storage of Pu'er: The Quality of Ripe Teas May Deteriorate
All foods have an optimal consumption period, and tea is no exception. The best flavor is achieved within a specific timeframe, after which the taste may change. Contrary to popular belief, Pu'er tea does not necessarily improve indefinitely with age.
During the wet-piling fermentation process, ripe Pu'er transforms tannins into secondary metabolites with reduced astringency, as well as dimethoxy and trimethoxy derivatives with strong Antioxidant properties. It also produces thearubigins, theaflavins, and theanines, which enhance the color and flavor of the tea.
These substances are highly beneficial to the body and are the primary functional components of ripe Pu'er. After the initial period following fermentation, during which the tea reaches its peak flavor, these substances gradually break down during storage.
Therefore, there are time constraints for storing and drinking ripe Pu'er, and it should not be assumed that all Pu'er improves with age.
In conclusion, raw Pu'er is generally more suitable for long-term storage compared to ripe Pu'er. However, proper storage conditions are crucial for preserving the value of raw Pu'er. If stored improperly, the tea can deteriorate, rendering previous efforts futile.