Refrigerator bag: what it is, how it works, how long it lasts cold?
Keep food fresh, chilled or even frozen outside the home and without a stationary refrigerator can be easily and simply with a thermal bag. For those, who has not yet acquired such a useful accessory, definitely, will be interesting to know, how a cooler bag works and what its effectiveness depends on. Let's understand!
Types and principle of operation of cooler bags
Refrigerator bags on store shelves are now visible and invisible. They come in different forms, colors and sizes. However, functionally such accessories are divided into:
- thermal bags;
- bags with cold batteries;
- car refrigerators, able to cool the air inside.
Let's look at these types of thermal bags in a little more detail.
Thermo bag, can only keep cold. It is arranged on the principle of an ordinary thermos, moreover, such an accessory can not only maintain low temperatures, but also keep the food hot. That is, you can always enjoy ice cream on the beach or treat your friends to a warm pizza on a picnic outside the city.
The thermo-bag is arranged very simply - it has an insulating foil layer inside, example, foamed polyurethane or foil insulation. Such a bag closes tightly and can maintain the same temperature inside the chamber for 2-3 hours. This bag is very convenient to use, if you lead an active lifestyle and spend a lot of time on the road and on your feet. The bag can be worn on the shoulder. There are models, made in the form of backpacks, and after use, such an accessory twists and does not take up much space. There are also thermo-boxes. They have a rigid construction, and as an insulating material can be foam.
If you buy fruit or drinks at the market on a hot summer day, put them in a regular thermos bag and go to nature and you will have to enjoy warm fruits and drink warm drinks.
But the bag with cold batteries will be able to help you in this situation and cool down a bit of purchased products. Essentially, this is a regular thermos bag with a thick layer of insulation inside. But in the complete set with such purchase cold accumulators - tight bottles with a salt solution or special gel inside are on sale also.. Such a battery must first be frozen. If the frozen container is placed in a thermo bag, then the saline solution will thaw very slowly, giving the cold food inside. The use of batteries increases the storage time of products inside the thermos bag - by about 10-12 hours.
However, there are bags-containers, able to actively and long-term cool the air and products inside. Such devices are powered by an outlet or cigarette lighter. It is thanks to this, the car refrigerator can work as long as days. Usually, such containers are the largest and are designed for motorists, travelers and those, who goes on vacation to nature with a large company.
What determines the retention time of the temperature inside the thermal bag?
Of course, buying a cooler bag, we all want, that our acquisition proved to be as effective as possible and lasted as long as possible. That is why, choosing one or another model, focus on the thickness of the insulating layer, ergonomics and the device of your purchase, presence or absence of cold accumulators, etc.. d.
Remember, that bag is made of dense material, with a reliable fastener and a safety valve, having a thick insulating layer, able to maintain temperature, 15 ° below, than the environment. However, without cold accumulators, this effect will be short-lived - about 3 hours.
By the way, we strongly do not recommend buying a cooler bag, if you are unsure, that the thermolayer in it is more 0,8 div. Less thickness of polyurethane or foil insulation is simply not able to keep cold or heat inside, longer, than 1-1,5 years.
If you get cold batteries or do it yourself - the shelf life of products in the chamber of the thermal bag increases by at least 6 hours. And the temperature can be 20-25 ° lower, than out of the bag. With the right placement of products in the middle and a sufficient number of cold batteries (on 1 l of products - 50 g cooler), the retention time inside the bag is from 12 to 24 hours. Depends again on the thickness of the thermal layer.
Cold accumulators can be bought ready-made. And you can use the tools at hand - ice packs, bottles with frozen water or plain saline (per pint of water - 3-4 tablespoons of salt). You can use granular filler from clean baby diapers. It must be wet, remove from torn diaper and freeze in package.
Before bookmarking products, try to cool the bag itself. Example, place it in the refrigerator compartment, and put something very cold inside. All products to be frozen are better not just to cool, and freeze well. Well, and it is better to pack each product in newspaper or food foil. Stacking products, try to evenly place the cold accumulators - purchased or made at home. Leave a couple of batteries at the bottom of the bag and under the lid of the bag. Remember, competent stacking of products - plus 1-2 hours to keep cold inside!
By the way, the frequency of opening the bag also affects the time of maintaining the temperature, and even its location. If you put the most dense and reliable bag in the sun or will often look inside - long-term cooling and maintaining the desired temperature you will not get. The thermal bag should be kept in the shade or in a cool place, also, it can be covered with a blanket or other things, which will interfere with heat transfer. To open the bag less often, buy a model with quick access valves - small side fasteners, which allow you to get out of the bag a small product or a bottle of water, without opening it and without letting warm air in the middle.
By the way, all the same rules apply in the case, if you need to keep food warm. Only cold batteries do not freeze you, and heat in hot water.
What do you need a cooler bag
The scope of use of an isothermal bag is extremely wide. Think for yourself:
- You can make large purchases of products, not worrying about their preservation. Even an afternoon walking around the market on a hot July day, you can be absolutely at ease with the freshness of purchased meat or dairy products, if you carry them in a thermal bag with cold accumulators;
- You can bring cold drinks, ice cream and other products on the beach;
- You can store the necessary cosmetics and medicines in a thermobag, which cannot be stored outside the refrigerator;
- You can bring food, perishable on a long trip (to nature, to the sea, to the country, on a camping trip);
- You can save pastries or other dishes, warm drinks, even if you have a picnic or a country picnic;
- You can hire, teaching, Workout your lunch in a small thermo container;
- You can safely wait for an unexpected power outage, repair or defrost of the refrigerator without loss of products from the freezer;
- You can store your catch in fishing or hunting meat in a thermal bag.
Some sensible housewives get several thermal bags of different sizes for different needs. In short, just buy or make a cooler bag with your own hands, and, believe me, you will not stand idle!
A real mini fridge - how it works
As we have said, except isothermal bags, there are also mini-refrigerators with the possibility of autonomous operation. These are rigid plastic or plywood boxes with a very thick isothermal layer of foam or foam, as well as foil inner chamber. in addition, when connected to electricity or car battery, such a device begins to generate cold, acting on the principle of an ordinary household refrigerator. Mini-refrigerators also have a small amount of refrigerant, compressor and tube system. When the power is on, the compressor begins to drive the refrigerant through the capillaries of the device, the air inside the mini-refrigerator compartment starts to cool down.
Sometimes, gas in cylinders is used instead of electricity. However, keep in mind, that 5 liters of cylinder will be enough for you for a week, not more. And yet, such an installation can be transported from place to place - it can only operate stationary.
More advanced devices work on the basis of this phenomenon, as heat absorption at the junction of two semiconductor materials. This phenomenon is known as the Peltier effect. Such a mini-refrigerator can receive energy from a simple cigarette lighter socket in the car or from a built-in generator. This model will be completely autonomous, it can be put in the country or carried in the trunk of a car.
As you can see, technology continues to move forward, making a person's daily life as comfortable as possible even there, where there can be no talk of civilizations. Now you have the opportunity to drink a cool drink, sunbathing on the beach, even if there are no shops nearby. Now you can go on long picnics and eat fresh food, without the risk of gastric upset. You can safely defrost and disinfect the refrigerator, without breaking my head, where to go a mountain of frozen products.
in addition, knowing the principle of operation of the cooler bag, you will be able to choose a really practical and effective model, and use its full potential. Always keep up with the times and live comfortably!
