What is a thermos, everyone knows. This vessel, which allows you to keep the temperature of the product placed inside, has found its application in various areas of life. The thermos accompanies climbers, conquerors of turbulent rivers, and various other travelers on their difficult journey. Fishermen, mushroom pickers and just lovers of outings also prefer to have a supply of a hot drink with them.
Thermos comes in handy in everyday life. Thanks to him, it is possible to eat a hot homemade dinner anywhere, and even at home, where there are no problems with heating food or water, this vessel is useful for brewing and infusing medicinal plants and fragrant herbal teas.
There is no doubt that a thermos is a useful thing, but how to choose the best one from the many available models? What criteria to focus on when buying, in addition to price, design and manufacturer?
The main selection criterion is the purpose of the thermos
First of all, you should figure out for what purposes it is needed, because the best thermos is the one that benefits. Such vessels are for drinks, for food or universal.
Thermoses for drinks
Thermoses for drinks, as a rule, have a narrow neck, closed with a cork. Usually it has a valve that allows you to pour out the contents without interference. This design contributes to a longer preservation of the temperature of the drink, since the most significant heat loss occurs through the lid. These thermoses are very popular with outdoor enthusiasts, which partly determines the shape of the vessel: a narrow, tall object can be easily placed on top of a bag or backpack. It does not require much space, but will always be at hand.
A fundamentally different type of thermoses for drinks is pump-action. It is also designed for liquids poured through a pump in its lid. This is very convenient — the thermos does not need to be tilted for fear of spilling the contents, and it cools down much more slowly. But these designs have volumes of more than 3 liters and the corresponding dimensions, so they will be the best solution for trips to nature with a family or a large company.
Another type of thermos for drinks is a thermo mug. This product is not intended to be carried in backpacks and bags and cannot retain heat for a long time, as it has the simplest non-screw lid. But stretching the pleasure of hot tea or coffee will help anywhere: on a trip, at work, on a fishing trip. Fans of ice fishing especially appreciate thermal mugs, because they can even be put on the snow, without fear that the tea will instantly cool down.
Expert advice! When buying a thermos for drinks, it is best to choose more voluminous ones. Of course, if the task is not to save as much as possible in weight. The larger the volume of the vessel, the longer it keeps warm, therefore, even for travel, 1 liter is better than 0.7 liters.
Thermoses for food
Thermoses for food differ, first of all, in a wide neck through which it is convenient to fold and remove food. It is customary to take lunch with them to work, and hence one more of their features follows — a small volume corresponding to one serving.
The so-called thermoses are also intended for food. Behind the heat-insulating walls are three small hermetically sealed food-grade plastic containers. Naturally, the size of such a vessel turns out to be rather big, but you can put a separate dish in each of the containers.
Universal thermoses can be used for both food and products. They have a wide flask and a lid, like food, but this lid has a valve for liquid. Very convenient in cases where there is no clear constancy in the nature of the content.
FROMexpert tip! If before buying a thermos it is difficult to decide on its purpose, then it is better to buy for drinks with a narrow neck. Such thermoses retain heat better, besides, practice shows that most often these vessels are used to transport liquids.
Having decided on the purpose of your future purchase, you need to move on to considering the characteristics of suitable options. You can start with the materials from which the body and bulb are made.
Everything is simple here. It is either metal or plastic. A thermos with a metal case is stronger, but a plastic one can be multi-colored and with drawings.
Expert tip: For home use, any will do, but otherwise it’s better not to give up strength for the sake of design. A thermos with a metal case can be fearlessly dropped even on stones, and nothing will happen to it, but a plastic case will not forgive this.
Glass mirror flask, which is now used quite rarely. The advantages are that it is easy to wash, it does not absorb the smells of products and does not distort their taste. If the flask is damaged, then you can buy a new one and replace it without throwing away the thermos. However, with all these pluses, it has one significant minus — great fragility.
A plastic flask, on the contrary, has only two advantages: low weight and strength, but it has a number of disadvantages. Plastic absorbs food odors, and, moreover, has its own. When heated, it can release harmful substances, it is poorly washed. The difference in the thermal expansion coefficients of plastic and metal spraying leads to the fact that after some time it will begin to fall off, so it is better to avoid thermoses with a plastic flask. The only thing for which you can buy such a thermos is for the so-called technical needs. For example, warm up a frozen car lock.
A steel flask is the best option, especially for lovers of an active lifestyle. It is durable, does not emit harmful substances when heated, is washed a little worse than glass, but much better than plastic.
Expert advice! Thermoses with a glass flask, which do not distort the taste of the product, are ideal for home use — you can brew fragrant tea and aromatic herbs in them. For all other cases, it is better to choose a thermos with a steel flask — it retains heat just as well, but it will last much longer.
When thinking about choosing the size of a thermos, you need to keep in mind: the larger its volume, the longer the temperature remains, provided that the vessel is filled tightly and completely.
If you need a thermos for lunch, then a small one is also suitable, 0.25 — 0.7 liters. Such vessels are quite compact, fit in a regular bag and do not take up much space.
For trips and travels, it is best to take a container from a liter to two. Usually these are universal or thermoses for drinks. They have adequate weight and fit easily in a backpack.
A solid thermos, with a volume of 3 liters or more, is best for a summer cottage or for relaxing with a large company.
Buying and checking a thermos
Having decided on the main parameters: the purpose of the thermos, material and volume, you can go to the store. It is better to choose products from well-known companies, which even indicate the time during which the contents are guaranteed to retain their temperature. As a rule, such products have a guarantee, and the chances of buying low-quality goods are much less.
Having picked up a model that is suitable for the price and design, you need to carefully examine it so that there are no chips, scratches, dents and similar defects. A product with a steel flask cannot be suspiciously light, no matter what the seller assures.
Then you need to shake the thermos and make sure that nothing rattles inside. Extraneous sounds are a clear sign that the bulb is not fixed properly. The lid and cork should fit snugly so as not to release heat.
The next step is to check for foreign odors. It is necessary to unscrew the lid and smell the thermos inside. There should not be strong foreign odors, and if they are, it means that low-quality materials were used for manufacturing, which may well turn out to be toxic.
The purchased thermos remains to be subjected to the last test: a test in operation. To do this, pour boiling water into the vessel and check the temperature of the outer walls after half an hour. If they become warm, the thermos can be carried back to the store, as it is not airtight and will definitely not cope with its tasks.
After a day, it must be opened and the temperature of the contents checked. If the contents are slightly warm inside, then the purchase will have to be returned, but if the liquid is hot enough, then everything is in order with the thermos.