A modern refrigerator has long ceased to be just a freezer, having turned into a complex climate system that can extend the life of food by several days or even weeks.
The key element of this system is freshness zone a special compartment where ideal conditions are maintained for storing perishable food without subjecting it to freezing. This is where the meat retains its color, the fish does not lose its elasticity, and the greens remain crispy.
Many users do not even suspect that incorrect placement of products in the chamber nullifies all the efforts of engineers, reducing the shelf life of food. Understanding the physical processes occurring inside this compartment will allow you to save money and eat better.
Physical principles of operation of the zero chamber
The basis for the functioning of the freshness zone is the precise control of two parameters: temperature and humidity. Unlike the main chamber, where the temperature usually fluctuates between +3...+5°C, in the zero zone a regime is maintained that is close to 0°C, but does not fall below the freezing point of water.
At this temperature, biochemical processes in products slow down, which inhibits the proliferation of bacteria and the oxidation of fats. However, simply cooling the air is not enough, since at zero temperature the humidity must be strictly controlled, otherwise the food will either dry out or rot.
Technically, this is implemented in two ways: using a separate evaporator or by redistributing air flows. In simpler models, cold air from the main evaporator is directed into a special insulated box, where a fan maintains constant circulation.
In advanced systems Liebherr BioFresh or Bosch VitaFresh independent cooling circuits are used. This allows you to create completely different climatic conditions in different compartments of the same zone, which is critically important for dissimilar products.
⚠️ Attention: Do not fill the freshness zone with products to capacity. For the air circulation system to work effectively, it is necessary to leave gaps between the packages, otherwise the temperature inside the box will align with the main chamber.
Why do products not freeze at 0 degrees?
Water in products contains dissolved salts and sugars, which lowers the freezing point. Pure water freezes at 0°C, but meat or fish begins to crystallize at -1...-2°C. Therefore, the range from 0 to +1°C is the “golden mean”.
Types of freshness zones: wet and dry
Not all products require the same conditions. Vegetables and fruits “breathe”, releasing moisture, and require high humidity to avoid wilting. Meat and fish, on the contrary, quickly become covered with mucus in a humid environment, so they need “dry” freshness.
Manufacturers solve this problem by dividing the freshness zone into two types of containers. The first type is humid compartment (humidity control), where humidity is maintained at 90-95%. Here the air circulates slowly, which prevents the evaporation of moisture from the surface of the products.
The second type is dry compartment, where the humidity is about 50-55%. Such boxes often have active ventilation or a special design of dampers that allows the air to dry out. This is where raw meat, poultry and hard cheeses should be placed.
In some refrigerator models, for example, series Samsung Twin Cooling, modes are switched mechanically using a slider on the box lid. By closing or opening the holes, you regulate the flow of dry air from the freezer.
What and where to store: compatibility table
Correct sorting of products is the key to their long-term storage. It would be a mistake to put everything in one box, hoping for a miracle. Each group of products has its own biological characteristics that must be taken into account.
For example, fruits emit ethylene, a gas that accelerates ripening. If you put apples next to greens, the latter will turn yellow many times faster. Therefore, division into compartments is not just marketing, but a necessity.
Below is a table that helps you navigate the placement of various product categories depending on the type of freshness zone:
| Product type | Recommended compartment | Shelf life (approximate) | Features |
|---|---|---|---|
| Fresh meat, poultry | Dry zone (0°C, 50%) | 3-5 days | Do not wash before storage |
| Fish and seafood | Dry zone (0°C, 50%) | 2-3 days | Best in an airtight container |
| Leafy greens, herbs | Humid zone (0°C, 90%) | 7-10 days | Requires high humidity |
| Berries, soft fruits | Humid zone (0°C, 90%) | 4-6 days | Keep away from condensation |
| Hard cheeses, sausages | Dry area or shelf | 10-15 days | Need ventilation |
It is important to note that ready-made meals, soups and open canned food are not intended for the freshness zone. Their place is on the middle shelves of the main chamber, where the temperature remains stable around +4°C.
Temperature and humidity control
Climate control in the freshness zone can be mechanical or electronic. In mechanical systems, you manually move a damper to change the ratio of air being mixed. This is simple, but less accurate.
Electronic systems, such as Electrolux FreshZone or LG Fresh Balanceruse sensors and microprocessors. The user selects the type of product on the display, and the refrigerator itself regulates the operation of the dampers and fans.
Particular attention should be paid to the preliminary preparation of products. If you put a hot pan or just washed wet vegetables in the freshness zone, the sensors may not have time to react, and the microclimate will be disturbed.
☑️ Preparing products for the freshness zone
Some models have a “quick cooling” function. It temporarily increases the operation of the compressor to quickly cool newly loaded products to the desired temperature.
⚠️ Attention: The characteristics of the equipment may vary depending on the model and year of manufacture. Before using new functions, read the manufacturer's instructions, as the location of the controls may differ.
Common operating errors
Even owners of expensive refrigerators often make mistakes that reduce the effectiveness of the freshness zone to zero. The most common of them is storing products in plastic bags without access to air in a “dry” zone.
As a result, a greenhouse effect is created inside the bag, condensation does not evaporate, and the product deteriorates faster than in a conventional chamber. It is better to place meat and fish in a dry area in open containers or special perforated containers.
Another mistake is overloading the boxes. As already mentioned, the air must circulate. If you fill the box to the top, the cold simply will not reach the products in the center, and they will begin to deteriorate.
Also, you should not store products with a strong odor (smoked meats, some cheeses) next to delicate products (butter, berries) in the freshness zone, if the refrigerator model does not provide hermetically sealed odors.
Care and maintenance of the zero zone
The freshness zone requires regular hygiene. Since the temperature here is close to zero, bacteria multiply more slowly, but do not disappear completely. Periodically (every 1-2 months) the boxes must be removed and washed.
For washing, use warm water and a mild detergent. Aggressive chemicals and abrasive sponges cannot be used - they can damage the plastic or antibacterial coating, if any.
Pay special attention to drainage holes, if they are provided for in the design. They can become clogged with food particles or mold, which will lead to stagnation of water and increased humidity where it should not be.
After washing, be sure to wipe the drawers dry and let them dry completely before putting them back. Moisture on the walls can temporarily disrupt the temperature regime.
Benefits of use for health and budget
Using the freshness zone is not just a matter of convenience, but also economic benefit. Products stored under optimal conditions retain their vitamins and microelements much longer.
For example, vitamin C in vegetables at a temperature of +5°C is destroyed faster than at 0°C. The meat retains its structure and does not lose its “meat juice” when thawed, remaining juicy after cooking.
From a financial perspective, you buy groceries less often and throw away less spoiled food. This is especially true for families purchasing food in large quantities for the week.
In addition, the presence of such a zone allows you to defrost meat and fish directly in the refrigerator, which is the safest method of defrosting from a sanitary point of view.
Is it possible to freeze food in the freshness zone?
No, the temperature is in the freshness zone maintained above freezing point (usually 0...+1°C). The food may become very cold, but no ice will form. Only the freezer compartment is intended for freezing.
Why does condensation appear in the freshness zone?
Condensation may appear due to frequent opening of the door, storing food in open containers in a humid area, or a malfunction of the moisture removal system. Check the tightness of the drawers.
Does the fullness of the refrigerator affect the operation of the freshness zone?
Yes, it does. The refrigerator must be filled at least 30-40% for stable operation of thermal stabilization. An empty refrigerator operates less efficiently and consumes more energy.
Do you need to defrost the freshness zone?
In refrigerators with the No Frost system, manual defrosting is not required. Drip systems may require periodic defrosting of the entire refrigerator, including the fresh zone, if ice forms there.