You cannot drink black tea overnight.

Although there is no evidence to support that overnight tea causes cancer, tea is a good "culture medium" for unknown bacteria, and some pathogenic bacteria can even multiply in overnight tea. Sometimes after drinking a pot of tea and leaving the rest overnight, you will find that the tea becomes turbid. In warm and humid weather, white hairy "mold" can even grow overnight. Drinking this kind of tea may cause gastroenteritis and other problems.

Extended information:

Dark tea, represented by Pu'er tea, is a post-fermented tea with relatively coarse raw materials. The characteristic of dark tea is that it "becomes more fragrant as it ages" and requires a more intense boiling water brewing process to fully dissolve the ingredients contained in it. Loose tea tends to smell bad, while pressed brick tea also needs to be cooked.

When brewing black tea for the first time, you need to quickly wash the tea in 10 seconds. That is, first put the tea leaves into the cup, pour in boiling water, pour out the water after a while, then pour in boiling water, and cover. Put the lid on the cup. This not only filters out the impurities of the tea, but also makes it more fragrant and mellow. Subsequent brewing time is usually 5 minutes.

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