It's often said that one can taste the flavor of black tea. But do you know what constitutes the true taste of black tea? And why does black tea have such flavors?

【Sweet】

The sensation of sweetness when drinking black tea comes from two main categories: sugars and amino acids in the tea leaves. Black tea is a fully fermented tea. It is made from suitable fresh tea buds and leaves through typical processes like withering, rolling, fermentation, and drying. During fermentation, extremely complex chemical reactions centered on the enzymatic oxidation of tea polyphenols occur. The chemical components in the fresh leaves change significantly: tea polyphenols decrease by over 90%, while new components like theaflavins and thearubigins are produced. Aromatic substances also increase noticeably compared to the fresh leaves.

Most sugar elements are converted into monosaccharides, and simultaneously, the amino acids in the tea leaves increase. Therefore, black tea is characterized by its black leaves, red liquor, and a sweet, mellow taste. Its sweetness is generally more pronounced than other types of tea.

Generally, if the raw material is tender, the amino acid content in the tea leaves will be higher, resulting in a fresher and sweeter liquor. Conversely, the freshness and sweetness of the liquor will be less. This is why, even from the same tea plant and using the same black tea production techniques, the quality of Jin Jun Mei is entirely a grade higher than that of Zheng Shan Xiao Zhong.

【Sour】

Generally, tea will have a certain sourness after fermentation. However, if you clearly feel the tea liquor is sour, it might be because the tea leaves were piled too densely during fermentation or the fermentation was excessive. As black tea is fully fermented, over-fermentation or poor timing control, followed by drying, can lead to sourness.

Additionally, if black tea is stored for too long, becomes damp, or is improperly stored, it can develop a sour taste. The water temperature used for brewing is also a factor, which depends on the tenderness of the black tea. For delicate black teas not tolerant of high temperatures, using water that is too hot can make the sourness noticeably apparent.

Finally, let's talk about bitterness and astringency. Actually, compared to other tea types, the astringency of black tea is not so prominent. Generally speaking, human taste preferences are broadly similar. At their core, probably no one enjoys a bitter and astringent taste. Bitterness and astringency occur because the touch receptors on the surface of the mouth encounter undesirable substances and produce resistance, leading to a puckering sensation.

【Bitter】

The main substances forming the bitter and astringent taste in tea liquor are catechins and caffeine. Catechins, commonly known as tea tannins, are unique components of tea leaves, a type of polyphenol with bitter, astringent, and收敛性 properties. Caffeine is theine. It constitutes only 2%-5% in tea leaves and only 1%-2% in coffee beans. Therefore, its bitter component in tea leaves is several times higher than in coffee beans. However, because this component was first discovered in coffee, it couldn't be named theine. Ideally, it should be called tea caffeine. Caffeine also carries bitterness and is an important component constituting the taste of tea liquor.

A very important property of caffeine is bitterness. The theanine and tea polyphenols in tea leaves can mask this bitterness. So, when measured, tea leaves contain more caffeine, but coffee's bitterness is more direct. Comparing old tea leaves and young buds, you'll find old leaves are more bitter while young buds are not, even though measurement shows young buds contain more caffeine. This is for the same reason—the theanine and tea polyphenols in young leaves cover up the bitter taste.

Any tea liquor brewed from any tea leaves cannot be completely free of bitterness and astringency. It can only be reduced through appropriate cultivar selection, manufacturing processes, and brewing methods. Generally, the fermentation process in black tea significantly reduces astringency. Black tea made from finely selected materials and with excellent craftsmanship can be almost free of bitter and astringent sensations. Of course, the degree of bitterness and astringency varies among different varieties of black tea. For example, good Wuyi Mountain Jin Jun Mei, due to its tender selection and refined processing, can minimize bitterness and astringency to the greatest extent.