Many people find that the raw Pu'er tea becomes increasingly astringent with each Infusion, why is this so? Why does the astringency increase with the number of infusions?
The reasons for the strong astringency in raw Pu'er tea are multifaceted, including the rate at which the tea's compounds are released, the influence of catechins, the reinforcing effect of astringency, excessive leaf-to-Water ratio, too high water temperature when brewing young raw Pu'er, incorrect brewing time, improper Pouring technique, and the quality of the water used for brewing.
These factors cause the drinker to experience an increase in astringency with each infusion. This explains why raw Pu'er tea becomes more astringent as it is repeatedly steeped.
However, if the astringency is due to the natural release of compounds from the tea leaves and the tea is of good quality, the transformation happens quickly, allowing the astringency to convert into a sweet aftertaste before it can become overly pronounced, leaving the mouth feeling pleasantly moist. If the problem lies in the brewing method, then using the correct approach is essential to bring out the true flavors of raw Pu'er tea.
The Rate at Which Compounds Are Released
During brewing, amino acids, Caffeine, and theaflavins are released more quickly than the catechins that cause astringency. Therefore, when drinking raw Pu'er tea, one initially experiences the tea's aroma and sweetness before encountering the astringency.
The stimulation of nerve endings by catechins is a gradual process that takes some time to be noticeably felt by the body. It also depends on individual sensitivity; those with higher nerve sensitivity are more likely to perceive astringency than those with average sensitivity.
Astringency has a reinforcing effect, becoming stronger with the volume of tea consumed, the concentration of the tea, and the frequency of consumption within a given period. The greater the volume of tea consumed, the more concentrated the tea, and the more times it is drunk within a certain timeframe, the stronger the stimulation by tannins such as lipid-type catechins will be. This reinforcement increases the perception of astringency.
Improper Brewing Intensifies Astringency
The recommended leaf-to-water ratio for raw Pu'er is 1:15. Excessive leaf-to-water ratio leads to a higher concentration of soluble polyphenols, thereby increasing the perceived astringency.
Water temperature around 95 degrees Celsius is generally suitable for brewing young raw Pu'er. Higher temperatures cause a large amount of polyphenols to be released, increasing the content of astringent compounds and intensifying the perception of astringency.
Raw Pu'er is not a highly aromatic tea. Pouring boiling water directly onto the leaves makes the tea bitter and astringent. Instead, pour the water slowly along the inner wall of the brewing vessel.
Leaving the tea to steep for too long increases the content of polyphenols in the water, making the astringency more noticeable.
The quality of the water used for brewing is also a factor influencing the astringency of Pu'er tea. Water with high hardness has lower activity and dissolves fewer compounds from the tea, which can make the astringency more prominent.