What does heap fermentation of Pu 'er tea mean?

This is a process of making Pu 'er tea. In the pile fermentation of Pu 'er tea, damp heat created a good environment for yeast metabolism, enhanced the activity of enzyme and provided a heat source for the change of chemical composition of tea. The added mold can use various polysaccharides as carbon sources of sugar metabolism, produce a large number of polysaccharides and monosaccharides, provide sufficient nutrition for yeast, and then multiply rapidly. When providing an environment conducive to yeast reproduction, the quality of tea during processing is characterized by sweetness and smoothness. It can be seen that the formation of glycol quality characteristics of Pu 'er tea is directly related to the growth and decline of yeast. In other words, the quality characteristics of Pu 'er tea, such as aging, mellow and smooth, are inseparable from the dominant strains in the fermentation process.

In the process of fermentation, macromolecules of carbohydrates are broken down into small molecules of sugars and soluble sugars. Soluble sugar is an important substance that constitutes the taste and consistency of Pu 'er tea soup, and at the same time it is so-called "sweet" in sense. Protein contained in tea accounts for 15%~30% by mass, which is decomposed into various amino acids after processing, giving tea soup nutrition and umami taste; Aromatic substances and sugars produce terpenoid alcohols through complex biochemical reactions, showing old fragrance; Tea polyphenols are the most distinctive substances in tea, and the tea pigments formed after fermentation give tea soup a unique color and the quaint reddish-brown leaf bottom color of Pu 'er tea.

Therefore, yeast plays an important role in the quality formation of Pu 'er tea. If the amount of Pu 'er tea can be properly controlled in the process of pile fermentation, it can increase the effective nutritional components of Pu 'er tea and substances that have health care effects on human body, endow Pu 'er tea with unique dietotherapy characteristics, and help to form the sweet, mellow and fragrant quality style of Pu 'er tea. However, if it is not properly controlled, it will form unfavorable substances such as spicy, prickly, biting, hemp, hanging, locking and acid, which will affect and reduce the quality of Pu 'er tea. Therefore, the quality characteristics of good Pu 'er tea, such as sweetness, smoothness and mellow taste, are closely related to the role of yeast in pile-fermentation of Pu 'er tea.