How to remove tea stains from thermos cup

Since thermos cups have good heat preservation properties and can keep water warm for several hours, many people like to use thermos cups to drink water or tea in winter. However, if you use a thermos to make tea for a long time, a layer of tea stains will form on the inner wall of the thermos. Tea stains not only affect the taste of water, but also cause great harm to the human body. So, how to remove tea stains from thermos cup?

1. Toothpaste cleaning

Use your hands or a toothbrush to evenly apply toothpaste on the thermos, or directly squeeze a small amount of toothpaste on the inner wall of the thermos, let the toothpaste stay on the inner wall of the thermos for one minute, then rinse with clean water, and the tea stains on the inner wall of the thermos can be easily washed away. Because the abrasives, surfactants and hydrogen peroxide contained in toothpaste can remove tea stains and protect the cup.

2. Clean with edible salt

Soak a bottle brush or gauze in a small amount of table salt, and use the gauze or bottle brush dipped in salt to wipe the tea stains on the inner wall of the thermos cup. The effect is obvious. When salt meets water, it will produce hydrochloric acid, and the component of tea stains is calcium carbonate. The two react chemically to produce calcium chloride and bicarbonate, so the scale will disappear.

3. Vinegar cleaning

Soak the thermos in vinegar for 30 minutes, then scrub it with a toothbrush to effectively remove tea stains. This is mainly because vinegar is an acidic substance that can decompose the calcium carbonate in tea stains.

4. Citric acid cleaning

Pour a small amount of citric acid into the thermos with tea stains, add hot water to dissolve the citric acid, soak for ten minutes, and then wipe off the tea stains in the thermos with a cloth. Citric acid can be obtained in the form of squeezed lemon juice or a citric acid-enriched beverage. Because citric acid is an organic acid, it is safe and environmentally friendly to use it to remove tea stains.

5. Wash the potatoes

Cut two or three slices of potato peels and put them in a thermos, pour in 200 ml of boiling water, cover it with a lid and let it sit for 10 minutes, then shake it up and down vigorously a few times. You can see that the tea stains in the thermos are easily removed. Potatoes contain a lot of starch, which can absorb tea stains in the thermos.

6. Cleaning coffee grounds

The coffee residue can be used to wipe the inner wall of the thermos to remove tea stains, or you can directly use the thermos to make coffee and drink it, which can also remove tea stains. Because the activated carbon in coffee has strong decontamination ability and can absorb tiny dirt.