Why does green tea turn red after brewing for a long time?

For green tea, green tea is rich in theaflavins, which is the main reason why green tea is green or yellow-green when brewed. However, for theaflavin, it will oxidize with the oxygen in the air, and if the green tea is left in the air for a long time, the theaflavins will be oxidized into thearubigin or theabrownin, which will make the brewed tea soup turn red.

Normal! When green tea is brewed for a long time, the flavonoids in the tea are oxidized and polymerized, or turn yellow, or turn red.

But it is not recommended to brew for a long time, in fact, all the nutrients in the tea are in the first 2 courses.

The most important thing about tea is the first three courses, and the subsequent brewing is completely useless, which is equal to cold and white.

I hope you drink the tea ceremony.

Come on, don't be too reluctant, it's only when you give up that you are magnificent!

How quick it is to have a cup of tea and chat together!

The reason why the tea color becomes darker is mainly that the tea contains a certain amount of protein, tannin pectin substances, tea polyphenols and precipitates, which combine with calcium, magnesium, iron, etc. in the mineral water to form turbidity and precipitation, thereby affecting the turbidity of the tea. In addition, the oxidation of iron ions in the water displaces the tannic acid and tea polyphenols of the tea, which will convert the colorless hydroxyl group into a colored hydroxyl group, thereby deepening the color of the tea and giving it a tan color. This is similar to people cutting apples with iron knives, and the flesh on the surface of the cut gradually turns brown after air oxidation, which is also due to the interaction between iron and tannin pectin.

Therefore, it is better for tea lovers to choose mineral water with a low content of total dissolved solids.

Tea soup contains tea polyphenols, which are in contact with the air, and are more likely to undergo enzymatic oxidation into theaflavins (flavonoids), thearubigins (red), and theabrownins (brown) under humid and hot conditions. So the tea soup will become darker and yellower.

Green tea boiled red can be drunk, green tea is not fermented tea leaves, under normal circumstances, the color of the gas soup is emerald green or tender green, and after boiling the tea for a long time, the tea soup is oxidized, thus turning red, and secondly, when the pH value of the water used for boiling tea is greater than 7 (weak alkaline), the color of the tea soup will also turn red, but it is a normal phenomenon to drink, just pay more attention to it.

After the red phenomenon, if the quality of the tea soup is normal, there is no obvious change, you can drink, if it is left for too long, the tea soup appears to change the taste, rancid taste, etc., you can no longer continue to drink.

Whether it is boiling tea or making tea, green tea is not easy to soak for a long time, because green tea itself pays attention to the fresh taste, and long-term soaking will lead to a thick tea soup, so that you can't really taste the taste of tea.

Secondly, long-term soaking will also cause the substances in the tea soup to be oxidized, which will make the tea soup tend to be red. When the pH value of the water used to make tea is greater than 7, that is, it is weakly alkaline, and the color of the tea soup is easy to become dark and red. Because colorless tea polyphenols are easily converted into theaflavins or thearubigins in weakly alkaline water, this phenomenon is more obvious in teas with lighter soup color.

The above content refers to People's Daily Online-9 major effects Drinking green tea often has many benefits.

People's Daily Online-Expired green tea can't make black tea.

Summary. Tea problem: check whether the tea has deteriorated, whether there is oxidation, the tea is easy to get old if it is not stored properly, and the tea soup turns yellow after brewing, resulting in poor taste and unsightly color.

Too much tea: If you put too much tea, the soup will be yellowish and the taste will be strong.

Machine cut green tea: Machine cut green tea, the tea leaves are incomplete, many tea leaves will be cut in half, or broken points, and the tea soup of this tea will also be yellowish.

Why does green tea turn yellow after brewing for a long time.

Tea problem: check that the tea has no deterioration and no oxidation, and the tea is easy to get old if it is not stored properly, and the tea soup turns yellow after brewing, resulting in a bad taste and unsightly color. Excessive amount of tea in the year of excitation:

If you put too much tea, the soup will be yellowish and the taste will be strong. Machine cut green tea: Machine cut green tea, the tea leaves are incomplete, many tea leaves will be cut in half, or broken points, and the tea soup of this tea will also be yellowish.

Drinking it has no effect on the body, right?

First, it may be that you used boiling water to brew green tea. It is recommended to use 80 to 85 degrees of water to make green tea, because most green teas are relatively tender teas, and green tea is not fermented tea, which is more afraid of burning. Boiling water can easily burn green tea and turn it yellow.

Second, it may be that you have closed the lid tightly. We generally brew green tea in a glass, under normal circumstances, it is not necessary to cover it, if necessary, it is best to wait for it to cool down before covering, and the time is not too long. We all know that if the green tea is covered for a long time, not only will the green tea become unfragrant, but also the sour smell will be noisy, and the soup will become turbid and yellow.

Third, prolonged exposure to air. Sometimes we don't drink green tea after brewing it, but when you come back after you're done, the color of green tea is no longer turquoise or tender green, but also a more cloudy yellow. Fourth, there are too many bubbles.

It doesn't affect you, but it just affects the taste of the tea.

<>Oh, okay. I wish you a happy life [Bixin].

I don't know how serious the red you are talking about. First of all, green tea will definitely not be brewed red, the endoplasmic characteristics of green tea are originally clear soup and green leaves, if it is brewed red, it is not green tea. If it is the kind that turns yellow to red, then there are two possibilities: first, your tea is too large, and the steeping time is long, and the quality of the tea has been seriously damaged; Second, you brew old tea, not new tea, green tea pays attention to drinking new, and the quality has changed after aging.

If it's very red, then there's only one possibility, you're not brewing green tea. You can look at dry tea, black tea is characterized by red stems and red macro leaves, thin and tight cords, and the color is reddish-brown. Ripe Pu'er tea is also reddish-brown in color, and the cords are relatively thick.

However, these two types of green tea that you mistake for may not be high. There is also a type of tea called Moonlight White, which looks like a bud head, a bit like green tea, but it will have a characteristic that its leaves are black on one side. After this tea is brewed, the soup color is also red, and the aroma is very unique, which is a combination of black tea and Tieguanyin.

If none of the above is true, then you should find someone who regularly drinks tea to help you take a look at it, and don't drink anything messy.

Under normal circumstances, the color of green tea brewed should be faint green or yellow, but the green tea that some people buy is red when brewed.

Why does green tea turn red.

1. The water temperature is too high (the water temperature of green tea should be 80-85° for the best, and the water temperature is too high to harm the essence and efficacy of tea).

2. The grade of tea is too low (it may be mixed with aged tea or non-tea leaves).

3. The soaking time is too long (resulting in the precipitation of a large amount of tea polyphenols in green tea, and the soup color formed after oxidation with air is too heavy).

That's what a good green tea should look like.

Good tea leaves are fragrant and rich, the aroma of flower tea is even worse, the taste is pure, the teeth and cheeks are fragrant, the aftertaste is sweet and mellow, and the tea is clear and yellow; Inferior tea and fake tea have no tea fragrance, and the tea is turbid with cyan, exuding a clear odor and astringency.

Green tea trivia.

Green tea is a tea made without fermentation, which retains the natural substances of fresh leaves, and contains more nutrients such as tea polyphenols, catechins, chlorophyll, caffeine, amino acids, and vitamins. These natural nutrients in green tea have special effects on anti-aging, anti-cancer, anti-cancer, anti-bacterial, anti-inflammatory, etc., which are unmatched by other teas. Green tea is a tea made from the new shoots of suitable tea trees through typical processes such as killing, rolling, and drying.

The color of its dry tea and the tea soup after brewing, and the bottom of the leaves are mainly green, so it is called green tea. Green tea is the fresh leaves picked by high temperature first, killing various oxidases, keeping the tea green, and then rolled and dried, clear soup green leaves are the common characteristics of green tea quality. The scope of green tea production in China is extremely extensive, Henan, Guizhou, Jiangxi, Anhui, Zhejiang, Jiangsu, Sichuan, Shaanxi (southern Shaanxi), Hunan, Hubei, Guangxi, Fujian are the main green tea producing provinces in China.

Classification of green tea.

According to the production technology of the process, green tea can be divided into: roasted green tea, dried green tea, roasted green tea and steamed green tea.

1.Fried green is a kind of long fried green tea, which is divided into: long fried green (is a long strip of fried green tea, after refining is called Mei tea), qu fried green (is a kind of strip-shaped curly fried green tea), flat fried green (is a flat shape of fried green tea), special fried green (is a kind of fried green tea) and round fried green (is a kind of bead-shaped appearance of fried green tea).

2.Roasted green tea is a kind of green tea that uses drying method to dry green tea, and is divided into: strip type (strip roasted green is a famous tea with delicate picking and fine processing), curved type (curved roasted green tea is a kind of tea strip with curved or round roasted green tea), flat type, etc. (flat roasted green tea is a kind of tea strip with flat roasted green tea).

3.Steamed green tea is a kind of green tea that is rolled and dried after being finished with steam.

4.Sun-dried green tea is a kind of sun-dried green tea made by using sunlight, which is divided into: bud tip sun-dried green tea (bud tip sun-dried green tea is a kind of bud-tip sun-dried green tea with extremely high tenderness) and strip-shaped sun-dried green tea (strip-shaped sun-green tea is a kind of sun-dried green tea that forms strips on the outside).