In the rumor that overnight tea should not be drunk, drink easy to get cancer, the reason is that overnight tea contains secondary amines, can be converted into carcinogens nitrosamines. In fact, there is no scientific basis for this claim. Moreover, secondary amine itself is not carcinogenic, there must be the presence of nitrate to form nitrosamines, and to a certain order of magnitude to have a carcinogenic effect.
From the point of view of hygiene, tea exposed to poor sanitation in the environment, easy to breed corrupt microorganisms, so that the tea rancid and spoiled. This situation is not drinkable, drink a small diarrhea, big say no good.
If it is in a clean and tidy environment, tea preservation is not easy to deteriorate, you can watch the CCTV "Is it true? The program team on the "overnight tea can not drink" this statement to investigate, the conclusion is: overnight tea is safe and can drink.
Tea has a large composition of substances called tea polyphenols, as well as some vitamin substances it plays a role in preventing the formation of nitrites. It is a natural antioxidant. From the taste, flavor to compare, whether it is placed 12 hours or 24 hours of overnight tea as long as there is no deterioration, "although it has been steeped for a longer period of time, but it also has the tea should have the taste, Puerh pay attention to the flavor and mellow taste, overnight tea may also be better.
Precautions: "overnight tea" although many uses, high temperatures in summer, the tea is easy to rancid flavor, if set aside for 24 hours, do not drink overnight tea, so as not to cause diarrhea.
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