Most of the thermos cups are kept in a sealed way. Due to the structure of the tea itself, it will be fermented in a sealed condition, and the fermented tea will produce some substances that are harmful to the human body. Tea is rich in nutrients such as protein, fat, sugar, vitamins and minerals. It is a natural health drink. It contains tea polyphenols, caffeine, tannins, tea pigments, etc., and has a variety of pharmacological effects. The tea leaves are soaked in high temperature water for a long time, just like decoction with warm fire, tea polyphenols, tannins and other substances will be leached out in large quantities, making the tea water thick in color and bitter in taste.
Nutrients such as vitamin C will be destroyed when the water temperature exceeds 80 ℃, and long-term high temperature soaking will cause excessive loss, thereby reducing the health care function of tea.
At the same time, due to the high water temperature, the aromatic oil in the tea will quickly volatilize in large quantities, and the tannic acid and theophylline will seep out in large quantities, which not only reduces the nutritional value of the tea, reduces the tea fragrance, but also increases the harmful substances. If you drink this tea for a long time, it will harm your health and lead to various diseases of the digestive, cardiovascular, nervous and hematopoietic systems.
