How to clean a thermos from tea plaque inside: the best ways with video

Average time to read It takes ~ 3 minutes to read

How to clean the thermos from tea plaque inside? This question ever arises for every owner. Even if you wash the flask well and thoroughly after use, this does not guarantee that an unpleasant dark residue will not occur. The peculiarity of tea and the tannins contained in it is that the insoluble fractions simply have nowhere else to go, except to settle on the walls. And the longer the tea is in a thermos - the denser the film.

Methods for cleaning a thermos

The reasons for the appearance of plaque

Phenols, tannins and an alkaloid thein are “responsible” for tea layers. Thanks to them, the drink has an astringent taste. But with a decrease in temperature, the above substances lose the ability to make a solution, and they stand out in the form of an oily film. It shimmers with rainbow colors and has a pearly shade. In black tea, which is undesirable for more than 5 minutes, it is formed more than in green tea.

If you continue to drink a cooled drink, the film will enter the stomach, where it will not do any harm to the body. But when you tilt the cup or the thermos (which is inevitable), the film will appear on the walls and will dry out soon.

By the way, if you regularly observe a dense coating in the cup, drinking it hot is an indication that the tea is excessively strong.

There is another version that the harder the water you drink, the more dense the coating will be. The longer the cold tea stands, the denser the film on it. Therefore, use spring or bottled water if possible.

Tea in a thermos

How to clean tea plaque inside a thermos

How to wash a thermos from tea plaque inside? There are many ways in the world, but the result depends on what material the bulb is made of. There are 2 types - glass or stainless steel. Glass is more fragile, but it is less capricious in leaving.

But there is always a cleaning agent in the house, because their choice is quite wide. All of the recipes listed below are indicated for the most common thermos flask - 750 ml. If you have more dishes, increase the dose.

Vinegar, citric acid or lemon

In this case, the acids contained in these substances “work”. The only question with them - how to clean a metal thermos from tea plaque - will not be solved. Acids are quite aggressive, so they negatively affect metal, and even stainless steel. But there will be nothing to the glass.

Any vinegar (natural or synthetic), with a concentration of 6-9%, acts as a solvent. It should be placed in a thermos (a third or half), pour boiling water (or boil the whole composition), close and leave for a couple of hours. There is an option to pour vinegar undiluted (but not the essence) for a shorter time. Acetic acid is hygroscopic and simultaneously absorbs all unpleasant odors. Then drain the liquid, wipe the walls of the flask and wash well.

The most environmentally friendly way than to clear a thermos of tea plaque: cut into small slices lemon, Pour it with boiling water in a flask and hold the night. This method is also good because the nasty aroma will disappear.

Lemon Slices

Lemon acid - an inexpensive (along with soda) and effective way than washing a thermos from tea plaque. Pour a couple of tablespoons (optionally with a slide) of acid into the dishes, pour boiling water and (depending on the degree of layering) let it stand for several hours or longer. Rinse the flask under running water and, if any stains remain, repeat the procedure again.

Baking soda

Sodium bicarbonate is used as a gentle soft abrasive in both types of flasks, and it is considered a quick way to wash the thermos inside. Put soda on a wet kitchen sponge and walk carefully along the walls. If you have a deep and narrow flask, then no fingers will reach the bottom. You can use a brush for dishes or a wand (for a sponge, pushing it deeper).

Strong or dense pollution will not succumb to soda the first time, and then another option should be applied, with soaking.

Baking soda


Here is the answer to the question: “How to clean a metal thermos from tea plaque?” Krupa remarkably eliminates plaque in stainless steel flasks. Here pearl barley, peas or rice act as an eco-sponge. Swelling from boiling water, porridge becomes loose and cleans surfaces well. Just a few tablespoons of raw grains is enough, and a couple teaspoons of soda is still added to enhance the effect.

Pour barley with boiling water, close the lid and leave for 30-60 minutes. Then shake the thermos well without opening it, and sponge the walls. Remember to throw in the trash.

Carbonated drinks

You probably already know that beloved by millions of children, Coca-Cola, Fanta or Sprite remove limescale from the kettle. Similarly, these undiluted cleaners remove tea deposits. Coca-Cola works especially well. Orthophosphoric acid contained in drinks will remove rust along the way, it is used for etching teeth in dentistry and when soldering metals.

If you change your mind about using this miracle drink inside, bring it to a boil, fill it in a thermos, close the lid and leave it for a while (it can be done until the morning).

Coca Cola


Sodium hypochlorite is a wonderful disinfectant, bleach and antibacterial drug. But use it, especially concentrated, should be used with caution. Whiteness contains aggressive chlorine, which can cope with plaque, but at the same time can damage welds, rubber gaskets or corrode plastic. And you will get a clean thermos that will not fulfill its primary function and keep warm. Therefore, pouring whiteness in its pure form is impossible.

But after applying the whiteness diluted with water (1: 1) on the sponge, you can wipe the glass flask. Thus, any musty and unpleasant aroma is “defeated”. Then the thermos should be washed thoroughly with soap and dried for a long time in the open. But especially sensitive noses will still smell for some time.


Ammonium chloride is an aggressive substance with a very pungent odor. It will remove the foul odor and plaque, but at the same time it can corrode the flask from stainless steel with prolonged contact. With a mixture of ammonia and chalk applied to a sponge or cloth, the inner surface of the glass flask is well cleaned, the main thing is not to soak and do it quickly.


How to remove a smell

Sometimes it seems that the flask is cleaned perfectly, but an unpleasant odor is still present. In this case, with absolute certainty, it can be argued that the case is in the lid. If it is made from natural cork, it absorbs odors best. And you need to not only wash the thermos from tea plaque, but also periodically disinfect the cork.

  1. A natural cork and plastic with rubber bands can be kept in concentrated saline for several hours. A natural cork is poured with a hot salt solution (but not boiling water) for several minutes.
  2. Never leave a tightly closed thermos. Even the washed and dried flask “suffocates” and an unpleasant odor appears in it. And the remaining few drops of moisture will lead to the appearance of mold, fungus and musty.
  3. Mustard helps eliminate odor. Her large tablespoon should be diluted in boiling water and pour this slurry into a container. Turn the thermos horizontally and change its position several times so that the mustard touches all the walls of the flask. And you will immediately solve 2 problems: how to clean the thermos inside of tea plaque and disgusting smell. Do this periodically, arranging the prevention of your insulating dishes.

What can not be used to clean a thermos

How to wash a thermos inside from tea is undesirable? Chlorine-based active substances (Domestos, Dressing duckling). They are not intended for processing food surfaces. And do not even try to use them in a metal flask. Not only is there a risk of ruining the dishes, you also get a drink with an unpleasant aftertaste.

Hard abrasives (metal brushes, scrapers, crushed eggshells, sand) can even clean the surface, but they will definitely damage the polished walls in both types of flasks.

Prevention of plaque and odors

One of the main ways how to clear a thermos from a scum - not to create it, drinking hot tea at once. The longer the drink is, the more plaque forms on it. The tea which has stood and drunk after 12 hours contains guanidine. It makes the heart beat faster, increases blood pressure and causes euphoria, which is why the infamous chifir is so loved in prisons. Remember - boiling already brewed tea and drinking it after a few hours is undesirable.

Other rules:

  • use soft water
  • do not brew tea for more than 15 minutes,
  • do not drink yesterday's drink.

The most important prevention of unpleasant odors is drying the thermos. Never leave it closed or turned upside down to any surface. An open flask should completely dry in air and then any unpleasant odor (even from strong smelling herbs that have soaked into the walls) will not appear.

With great interest I always read your comments to my articles. If you have any questions, feel free to ask them, leave, you are welcome, Your feedback in the form below. Your opinion is very important to me. Thanks to your criticism and thanks, I can make this blog more useful and interesting.

I would be very grateful if you rate this post and share it with your friends. This is easy to do by clicking on the social media buttons above. Do not forget the article you like Add to bookmarks and subscribe to new blog posts on social networks.

How to get rid of the smell in the dishwasher

How to get rid of the smell in the dishwasherCare

Content: Causes unpleasant smell Methods for cleaning How to prevent unpleasant smellJust because dirty dishes are put into the technique, this can contribute to the formation of...

Read More
Means for removing scale in coffee machines

Means for removing scale in coffee machinesCare

If you like coffee and you have a coffee machine, then you probably understand that periodically you need to clean it and remove all the scum. Manufacturers took care of coffee lovers and began ...

Read More
How to wash the refrigerator: housewife tips

How to wash the refrigerator: housewife tipsCare

Russia, Moscow region, Moscow+79041000555 It takes ~ 2 minutes to read A refrigerator in the kitchen is one of the most necessary items of household appliances. He requires careful attention...

Read More