Brewing tea with cold water not only releases more catechins but also reduces the caffeine content. Drinking cold-brewed tea on a hot summer day is not only refreshing and thirst-quenching but also healthier! Brewing a delicious cold-brewed tea is even easier and simpler than hot brewing, making it suitable for busy office workers, students, and drivers.
What are the benefits of cold-brewed tea
Drinking tea can calm the mind and cultivate character. Since ancient times, tea culture has primarily revolved around brewing with hot water. Modern experiments have confirmed that tea contains beneficial components such as tannic acid, catechins, and vitamin C, elevating tea to a health beverage. The trendy "cold-brewed tea" among young people, which involves steeping tea leaves in cold water, subverts tradition while being cool and refreshing. Many studies have found that the cold-brewing method reduces the content of caffeine, phosphorus, and tannic acid, offering better health guarantees.
Cold-brewed tea involves steeping tea leaves in cold water for about 10 hours, allowing the fragrance and nutrients of the tea to be slowly released. Experiments have found that compared to regular hot-brewed tea, cold-brewed tea offers many more benefits. The amount of catechins and polyphenols effectively released is similar, but the caffeine and tannic acid content is much lower.
The caffeine in tea leaves is easily dissolved at high temperatures. Excessive caffeine can accelerate the heart rate, cause calcium loss, and some people may experience periodic headaches, insomnia, and other symptoms. It can also affect the kidneys' absorption of calcium. The caffeine released from cold-brewed tea is lower, which can avoid these problems and reduce the burden on the stomach lining.
The tannic acid (tannin) in tea can prevent oxidation, promote fat enzyme decomposition, and reduce the risk of cardiovascular diseases. However, tannic acid binds with iron in the body, affecting its absorption. If iron levels are insufficient, oxygen supply is poor, which can easily lead to iron-deficiency anemia, making it difficult to concentrate and causing memory decline. With the cold-brewing method, the tea retains its sweetness, but tannic acid and caffeine are less likely to dissolve, adding to its health benefits.
Additionally, tannic acid varies depending on the tea's roasting process. Generally, the higher the fermentation level, the less tannic acid it contains, and the more vitamin C is lost. Unfermented green tea has a higher tannic acid content and more vitamin C.
The antioxidant effects of catechins have long been confirmed. When cold-brewed, the free-form catechins (EC, EGC) are higher than in hot-brewed tea. Overall, the content of various chemical components in cold-brewed tea increases with the steeping time, with the most significant change occurring within the first two hours. After a certain period, the amount dissolved does not change much. After 8 hours of steeping, the content of all components, except caffeine, is higher than in hot-brewed tea.
The antioxidant properties of cold-brewed tea increase with the steeping time and approach equilibrium after 12 hours. Its reducing power is comparable to hot-brewed tea; its ferrous ion chelating ability is 1.08 times that of hot-brewed tea; and its DPPH free radical scavenging ability and superoxide anion scavenging ability are comparable to hot-brewed tea.
Cold-brewed tea is characterized by being ready to drink whenever needed, such as when traveling or at work, in situations where boiling water is not available. As long as you have pure mineral water, you can enjoy tea. It can also save energy such as electricity or gas. Which teas are suitable for cold brewing?
However, not every type of tea is suitable for cold brewing. Generally, the longer the fermentation time, the higher the phosphorus content in the tea. For cold brewing, it is best to choose low-fermentation teas with lower phosphorus content. Among the most common teas, green tea has a low fermentation level, followed by oolong tea, while black tea, Tieguanyin, and Pu-erh tea have higher fermentation levels.
Making your own cold-brewed tea in the summer is hygienic, environmentally friendly, and cost-effective. It not only refreshes and quenches thirst but also has special effects on lowering blood pressure and uric acid. Six steps to brew healthy tea
How can you make delicious cold-brewed tea? You can easily complete it by following these steps:
(1) Prepare equipment: tea leaves, cold water, plastic bottles, filters, and other containers.
(2) The ratio of cold water to tea leaves is about 50 ml to 1 gram, which can be adjusted according to personal taste. Then, place it in the refrigerator to chill.
(3) After about 8-10 hours, you can pour out the tea and drink it. The tea will be mellow and delicious.
(4) If you have not finished the tea, put it back in the refrigerator immediately and do not keep it for more than 24 hours.
(5) After taking cold-brewed tea out of the refrigerator, try to finish it within two hours.
(6) Cold-brewed tea leaves should generally not be re-brewed.
It is recommended to put it in the refrigerator the night before, and you can enjoy the sweetness of cold-brewed tea when you wake up.
When using tea bags, make sure there are no small staples. A wide-mouthed bottle is more suitable for cold brewing, but never choose an iron can, as the tea will cause the iron to oxidize and rust. Do not store dry tea in plastic bags, as they can easily cause the tea to lose its flavor. Do not use glass jars, as sunlight can cause chemical changes with the tea. It is best to use a sealed, airtight, and light-proof white iron can.
Do not drink tea while eating, as the tannic acid in tea will reduce the absorption of iron.