The overnight tea is the tea that has been placed for one night. Objectively, judging from the time, the tea that was placed at 11 o’clock in the evening will be drunk at 7 o’clock the next morning, and the tea that was brewed at 7 o’clock in the morning will be drunk at 3 o’clock in the afternoon. The time is the same, but no one said that the tea that was brewed in the morning should not be drunk in the afternoon. Therefore, whether or not the overnight tea can be drunk is actually a matter of time and tea products, not an overnight problem.
It is not recommended to drink green tea overnight, because time will make the tea oxidized, and the taste is not good. We need to drink green tea in time. Pu’er tea, oolong tea, black tea and other tea products can be brewed after the night without a white film on the surface.
Some people also said that overnight tea was more poisonous than snakes! Because overnight tea will produce nitrite, and nitrite will be converted into carcinogen nitrosamine in the body, so overnight tea may cause cancer. At first glance, this sentence seems very reasonable, but can it really stand firm in the scientific perspective?
In fact, there are some nitrites in the water in nature, but after purification, the water fully meets the national drinking standards, so there is no need to worry too much. Moreover, even if the water is boiled repeatedly, the water content will decrease, but the concentration of nitrite in the water is also very low, which is a long way from poisoning!
In addition, some experts have conducted experiments on the rumor that overnight tea may cause cancer. They brewed Longjing, Pu’er and chrysanthemum tea respectively, placed them for 12 hours and 24 hours, and then compared them with the newly brewed tea. The experimental conclusion is that the overnight tea neither deteriorates nor has abnormal taste. The nitrite content is very low, even lower than that of plain water. This is mainly because the tea contains certain tea polyphenols, which is a natural antioxidant!
So, can overnight tea be drunk? The answer is: Of course! The only problem may be that after overnight storage, the tea will become dark and turbid, and the appearance will be reduced.
But if the overnight tea has been fermented by bacteria, there is foam in the tea, and there is a layer of white film like oil on the surface, it is generally that there are a lot of bacteria breeding in the tea, producing gas and some secretions, so it is not suitable to drink it again.