In a Cup of tea, there is a rich variety of flavors, and behind these flavors lies a marvelous combination of taste compounds.
The taste compounds in tea are diverse, including sugars, amino acids, phenolic substances and their oxidation products (primarily catechins), purine alkaloids (mainly Caffeine), and tea saponins. Together, they shape the unique flavor profile of tea.
Catechins, which have a high content in tea polyphenols, impart bitterness and astringency, particularly ester-type catechins. When tea is consumed, this bitterness mainly comes from the formation of insoluble substances through the reaction between ester-type catechins and oral mucosal proteins, leading to an astringent sensation. Simple catechins, on the other hand, provide a refreshing experience. For green tea, the impact of tea polyphenol content is complex. Within a certain range, taste scores are positively correlated with tea polyphenols, maintaining a harmonious balance of concentration, body, and freshness. However, beyond a certain amount, while the concentration of the tea increases, the freshness and body decrease, and the bitterness intensifies. The influence of tea polyphenols on the taste of tea cannot be judged by a simple relationship but must be considered in conjunction with their solubility, absolute content, and ratio to other taste compounds, especially amino acids.
Amino acids give green tea a mellow and refreshing mouthfeel. Theanine, an amino acid unique to tea leaves, is particularly important. Additionally, there are various other amino acids such as glutamic acid and aspartic acid. Not all amino acids impart umami; some are sweet or bitter. Amino acids derived from the hydrolysis of L-type proteins, which are common in nature, can impart tastes such as bitterness or sweetness to tea. These different taste qualities, when combined in various proportions and synergistic effects, create the rich and varied taste sensations in tea.
Purine compounds, primarily caffeine, are major taste components that impart a bitter flavor. Caffeine is volatile and its content decreases significantly with multiple infusions. Caffeine not only stimulates the central nervous system and activates brain cells but also affects the secretion of gastric juice and bile, which is one of the main reasons for the preference for tea. Anthocyanins are another source of bitterness, and when their content exceeds a threshold, the tea becomes distinctly bitter.
Sugars in tea, mainly monosaccharides and disaccharides, are present in low amounts but, due to human taste perception, can enhance sweetness after a slight bitterness is detected. This synergy between sweetness and bitterness provides a pleasant drinking experience.
In addition, Pectin and glycosides of phenolic substances in tea play a role in flavor formation. Water-soluble pectin gives the tea a thick and full mouthfeel. There are also metal ions in tea that can produce a salty taste, though this is often undetectable because it does not reach the threshold for perception.
A good cup of tea is a feast for the senses. From bitterness to sweetness, from freshness to fullness, every flavor is a gift from nature and a testament to the wisdom of tea makers. In savoring tea, we not only appreciate its unique flavors but also feel a sense of tranquility and peace. Let us immerse ourselves in the world of tea and savor the beauty and emotion that each cup brings. Whether enjoyed alone or shared with friends, tea brings endless joy and warmth. Let us be accompanied by tea and seek the true meaning of life in its fragrance.
In our busy lives, take a moment to Brew a cup of tea, let its delicate aroma linger, and allow your body and mind to relax and ease in its scent. Experiencing the secrets of tea flavor is experiencing the richness and diversity of life. Let us embark on a wonderful journey of life with tea as our companion.