There is a saying that "not bitter or astringent is not tea". Bitterness is the original taste of tea. The ancient name of tea as "bitter tea" has long been confirmed. But those who taste tea are definitely not tasting the bitterness, but tasting the refreshing taste, sweetness, and rejuvenation of tea, and experiencing the impact of tea soup on taste buds.
The main components of tea are tea polyphenols, caffeine, and theanine. Let’s analyze these three components!
1. What are the reasons for the tea soup "returning to sweetness"?
The first argument is the result of the transformation of astringency:
Professor Wang Yuefei, deputy director of the Department of Tea Science of Zhejiang University, expressed his views in the book "Tea Culture and Tea Health" edited by him: "Tea contains tea polyphenols, which can be combined with protein to form a layer in the oral cavity. The impermeable membrane, the local muscle contraction of the oral cavity causes the astringency of the oral cavity, which makes us feel that the tea just drunk will have a bitter feeling. If the content of tea polyphenols is more appropriate, it will form a membrane with only one or two monolayers or bilayers The thickness of the film is moderate, and there is an astringent taste in the mouth at the beginning. After the film ruptures, the local muscles in the oral cavity begin to recover, and the astringency is transformed, and the feeling is regained." Therefore, Professor Wang Yuefei believes that "returning sweetness" is the result of the combination of tea polyphenols and protein.
Another way of saying:
believes that "returning Gan" is an illusion of the oral cavity, that is, the "contrast effect". McBurney and Professor Bartoshuk proposed in the article "The relationship between different taste qualities and irritants" published in 1979: "Sweetness and bitterness are a relative concept. When you taste sweeteners such as sucrose, you will find that water is a bit bitter. Yes, and when you taste bitter substances such as caffeine and quinine, you will feel that the water is sweet." And this phenomenon is a kind of contrast effect, so many people also think that this kind of illusion may also be one of the factors that cause reluctance.
Sugar:
Tea soup contains polysaccharides. These polysaccharides have no sweet taste, but have a certain viscosity, so they will stay in the mouth. Saliva contains salivary amylase, which can catalyze the decomposition of starch water into maltose, which has a sweet taste. Enzymes need a certain amount of time to decompose polysaccharides, and this difference in reaction time creates a feeling of "returning sweetness".
2. Should "good tea" have astringent taste?
As mentioned above, tea polyphenols, caffeine, and theanine are essential ingredients in tea, so should "good tea" have astringent taste?
1. The influence of environmental factors on tea quality:
Temperature and light are directly proportional to the content of tea polyphenols (high temperature, more light, more tea polyphenols and less theanine)
Temperature and light are inversely proportional to the content of amino acids (low temperature and less light, the tea picked has more amino acids and less tea polyphenols)
2. The influence of different processing techniques on tea quality:
It is certain that the post-processing of tea leaves is very critical, important and fatal.
3. On another picture, the ingredients and taste of tea
Judging the quality of tea leaves, and we talked about Mingqian tea, Yuqian tea, spring tea, autumn tea, summer tea... and so on. If you use the ingredients in tea to explain it, it is the tea polyphenols, Caffeine, theanine and some other ingredients, the content and proportion of these ingredients determine the quality of tea.
For example: low bitterness and astringency content, high freshness and sweetness content, then the result is quick sweetness, freshness and sweetness are obvious
Bitter, astringent taste is light, umami and sweet taste is strong, then the prominent fresh and sweet taste will cover part of the light bitter and astringent taste, making the bitter and astringent taste (especially astringent) less obvious.
This is why tea polyphenols cause astringency, and why tea with a high content of tea polyphenols is not astringent.