How to ferment black tea?

Question 1: How does black tea ferment at home? Fermentation is the key process to form the color, aroma and taste quality characteristics of black tea. Generally, the twisted leaves are put into a fermentation rack or a fermentation cart and enter a fermentation chamber for fermentation. Proper temperature, humidity and oxygen amount should be mastered in fermentation to meet the oxidative polymerization of tea polyphenol oxidase. ① Temperature: Generally, the room temperature is controlled at about 20 ~ 25℃, and the temperature of fermented leaves is kept at about 30℃. If the leaf temperature exceeds 40℃, it is necessary to stir and dissipate heat to avoid excessive fermentation and make the tea fragrant, light and black. Especially in high temperature season, cooling measures should be taken, and the blades should be thin to facilitate heat dissipation and cooling; On the contrary, when the temperature is low, the leaves should be thick and some heat preservation measures should be taken when necessary. (2) Humidity: keeping the air humidity above 90% is beneficial to improve the activity of polyphenol oxidase and the formation and accumulation of theaflavins; On the contrary, the air humidity during fermentation is too low, which is not conducive to the enzymatic oxidation of tea polyphenols, and intensifies the non-enzymatic oxidation, leading to the darkening of soup color and leaf bottom and the weakening of taste. ③ Spreading leaf thickness: generally 8 ~ 12 cm. Young leaves and leaflets should be thinned; Old leaves and big leaves should be thick. When the temperature is low, it should be thick; Dilute when the temperature is high. However, whether it is diluted or thickened, the leaves should be kept well ventilated during fermentation. Stir once in the fermentation process to facilitate heat dissipation and ventilation. ④ Fermentation time: The fermentation time of Kung Fu black tea is generally 2-3 hours, and that of broken black tea is generally 30-90 minutes. The grass flavor of fermented leaves disappeared, and a fresh fragrance of flowers and fruits appeared, and the leaves turned red, indicating moderate fermentation. Generally, spring tea is yellow and red and summer tea is red and yellow.

Question 2: How is black tea fermented?

Fermentation is the key process to form the quality of Kung Fu black tea. The so-called black tea fermentation is a series of chemical changes with polyphenol oxidation as the main body under the action of enzymes.

Generally, the air temperature in fermentation room is 24 d, 25℃, the relative humidity is 95%, and the thickness of spreading leaves is 8D 12cm. Fermentation suitability

The green grass of tea leaves disappears, and there is a fresh fragrance of flowers and fruits. Tea leaves turn red and yellow in spring tea and red and yellow in summer tea. Young leaves are red and even, while old leaves are often red and blue because of difficulties in changing.

Question 3: Three steps to be mastered in black tea fermentation: the production technology of Mulan black tea;

The physical changes in the primary processing of black tea are mainly manifested in weight reduction, leaf shape reduction and leaf color change to red. The essence of leaf reddening is chemical change. Leaf shape reduction and weight reduction include the reduction of dry matter and water, but mainly the evaporation of water.

Generally, the water content of fresh leaves is about 75%, which will drop to 4%-6% when making tea. In the whole primary production process, with the progress of the process, the change of moisture presents a decreasing law. Generally, withering loses 40%-50% of the original water content, kneading loses 2%-5%, leaf "fermentation" loses 50%-55%, drying loses 65,438+08%-25%, and finally the water content of leaves is fully dried.

From withering to "fermentation", the gradual reduction of water can produce three effects. First, the decrease of water content increases the concentration of each chemical component, the number of molecules in fruit juice per unit volume, the number of effective collisions between molecules per unit time and the speed of chemical reaction;

Secondly, due to the decrease of water content, the enzyme changed from the bound state to the free state, which enhanced its catalytic activity and accelerated the chemical reaction.

Thirdly, the water content is gradually reduced, which makes all kinds of chemical components undergo comprehensive and beneficial changes and forms good tea quality. In the process of withering, under the condition of constant temperature and humidity, water evaporation has the law of "fast first and then slow"

Question 4: Why does black tea ferment? I'm a biology student, so I'll give you a professional definition of fermentation.

The electrons released by the oxidation of organic matter are directly handed over to an intermediate product that is not completely oxidized by itself, and at the same time, energy is released to produce various metabolites.

Fermentation is to produce some secondary metabolites. Different degrees of fermentation will produce different intermediate products.

Related to tea, that is to say, different degrees of fermentation will produce different flavors and fragrances due to different metabolites.

Withering enhanced the enzyme activity of black tea, and made tea polyphenols fully oxidized in the process of rolling fermentation, forming the unique color and aroma of black tea. Finally, the enzyme activity was destroyed by high temperature drying, and the molding quality was fixed.

Question 5: What about the taste of black tea? The fermentation is incomplete, the leaves are green at the bottom, which conforms to the taste of normal black tea and has a astringent head.

Question 6: Is black tea fully fermented? Black tea is completely fermented.

Black tea is refined through a series of technological processes such as withering, rolling (cutting), fermentation and drying. Withering is an important process in the primary processing of black tea, which is called "black tea" in the primary processing. Black tea is named after the tea soup and leaf background color are red after brewing dry tea.

The main varieties of black tea are: Qi Hong, Huohong, Dianhong, Yue Hong, Quancheng Red, Quancheng Green, Su Hong, Chuanhong and Hong Ying. Among them, Qimen black tea is the most famous.

Question 7: How is black tea fermented? Fermentation is the key to the quality of Kung Fu black tea. The so-called black tea fermentation is a series of chemical changes with polyphenol oxidation as the main body under the action of enzymes. Generally, the air temperature in fermentation room is 24 d, 25℃, the relative humidity is 95%, and the thickness of spreading leaves is 8D 12cm. The green grass of tea leaves with suitable fermentation degree disappears, and fresh flower and fruit fragrance appears, with red leaves, yellow-red spring tea, red-yellow summer tea, tender leaves and even red leaves, and the old leaves are blue because they are difficult to change.

Question 8: Is black tea fermented? Let me study with you. I hope you like it.

black tea

Black tea is a completely fermented tea. Black tea is traditionally the only known tea in the west. Westerners prefer black tea. Black tea is mainly produced in China, Sri Lanka, India, Kenya and other places. Black tea is made by picking, withering, rolling, fermentation, drying and other steps, which is one more fermentation process than green tea. Fermentation refers to the oxidation of tea leaves in the air. Fermentation reduced the contents of tea polyphenols and tannins, and produced new components such as theaflavins and thearubigins, as well as aromatic substances such as alcohols, aldehydes, ketones and esters. Therefore, the tea leaves of black tea are black, or black is mixed with orange buds; Tea soup is dark red; The aroma is fragrant; Because there is no bitterness, it tastes sweeter and more mellow.

Black tea is also called fully fermented tea. Originated in Chong 'an, Fujian (now Wuyishan City). Withering, kneading, fermenting and drying. The quality is characterized by red soup and red leaves. According to the different production methods, it can be divided into ethnic black tea, kung fu black tea and red broken tea. Location: Yunnan, Hainan, Guangdong and Guangxi. Tea is the main export product of China.

The main varieties are Qi Hong, Dianhong, Hong Min, Chuanhong, Poinsettia, Ninghong, Yue Hong, Hong Hu, Su Hong and Taihong.

Picking one or two leaf buds to two or three leaf buds, withering, rolling, fermenting, baking, refining, screening, closing the door, screening, cutting, winnowing, picking, conditioning, cooling and splicing.

Yunnan Kung Fu black tea is also called Dianhong. Kung Fu black tea is produced in Lincang, Baoshan, Simao, Xishuangbanna, Dehong, Honghe and other places along the Lancang River in Yunnan. Developed in 1939. Picking Yunnan big leaf species with one bud and two leaves, the first leaf with one bud and three leaves and the single leaf with the same tender leaves, and carrying out primary processing, withering, rolling, fermentation and drying; Refining is divided into four main processing routes: self, long body, round body and homo sapiens, which are formed by screening and splicing. The rope is tight, straight and fat, the color is oily, the golden hair is exposed, the seedlings are beautiful, the soup is red and transparent, the taste is mellow and sweet, the aroma is rich and lasting, and the leaves are red and bright.

Black tea is different from green tea. Green tea will lose its flavor over time, but black tea can be preserved for a long time and remain unchanged, so it can adapt to long-distance transportation. This may be one of the reasons why black tea spread to the west.

Question 9: How to tell whether fermented black tea belongs to fully fermented tea? It is made from tea buds and leaves through typical technological processes such as withering, rolling (cutting), fermentation and drying. Its quality is characterized by red leaves and red soup, which is fragrant, bitter and mellow.

There are many kinds of black tea, so its natural origin is wider. According to its processing method and tea shape, it can be generally divided into three categories: small black tea, kung fu black tea and red broken tea.

First, the characteristics of high quality black tea:

(1) Appearance: the cable is compact and uniform.

(2) Color: black and oily, and the bud tip is golden yellow.

(3) Aroma: Small black tea has the aroma of pine smoke; Kung fu black tea smells sweet; Chuanhong has the smell of orange candy.

(4) Soup color: the soup color is red, and there is a bright gold circle along the edge of the bowl, which is "cold and turbid" after cooling.

(5) Taste: The tea soup tastes mellow and sweet.

(6) Leaf bottom: The bud leaves are neat and uniform, soft and thick, and the color is bright and vivid.

Second, the characteristics of inferior black tea:

(1) Appearance: uneven size and length, rough appearance and many impurities.

(2) Color: the leaves are dark and the buds are black, or the tea leaves are bluish gray and silvery white; Thick old leaves are dry and red in color.

(3) Aroma: the aroma is weak, turbid, short-lasting or smelly.

(4) Soup color: the soup color is dark or light and turbid.

(5) Taste: light or rough.

(6) Leaf bottom: The flowers at the leaf bottom are blue-black and do not spread.

Question 10: It is said that black tea is fully fermented. What are the benefits of fully fermented tea? Fermented tea is relatively harmless to the stomach, which can regulate the blood lipid and blood sugar of human body and accelerate the digestion of human body. Therefore, people with a bad stomach want to drink tea to lose weight, and they can drink more fermented tea, such as black tea, oolong tea and Pu 'er tea.