Cooling foods rapidly, but gradually, is essential to preserve food safety and quality for a longer period of time. It also ensures a better food presentation.
At a temperature below 4°C the microbiological activity of germs stops, disabling them from developing and preventing food decay.
Microbiological activity decreases exponentially as the temperature drops.
During the freezing process, the water in the foods are turned into ice. When the product is frozen slowly, larger ice crystals are formed, which damage the cell walls. This causes a loss in aroma, juice, and nutrients. It is not only important to freeze foods rapidly, it is equally important to freeze them gradually. Sudden, heavy fluctuations in temperature lead to frictions, causing cracks in the product surface.

Advantages of CO₂ cooling and freezing

• No cracks in the product surface
  CO₂ has a sufficiently low temperature (78.5°C) to create an ideal heat transfer, allowing the product to cool rapidly, but gradually and uniformly.
• Shorter cooling and freezing times than mechanical methods, resulting in a faster production speed.
• Better food quality because of smaller crystal formation; results in a better preservation of nutrients and aroma. Secondary infection of foods is ruled out because of the bacteriostatic effect of CO₂.
• Better food presentation. CO₂ takes oxygen out of the air, preventing foods from oxidizing. Because of a rapid cooling process, the food product's color is unaltered and shrink loss is reduced to a minimum.
• Limited weight loss i.e. max 0.2% as opposed to 5% during mechanical freezing methods. As a result, CO₂ cooling realizes a surplus per kg.
• Leaves no residue. The fine CO₂ snow sublimates into gas, leaving no residue, unlike water ice, for example.
• Energy-saving method. The CO₂ cooling method is only 12.5 % energy-dependent, while mechanical freezing is entirely energy-dependent (100% electricity) and nitrogen freezing is 50% energy-dependent (both the air separation unit and gas liquefying unit run on electricity).
  

• Cryogenic freezing using CO₂ is especially energy-saving in batch processes since the freezer is turned off after the product is frozen. Mechanical freezers, on the other hand, need to be running non-stop. Moreover, it will only take a few minutes to start up the freezers after cryogenic freezing.
  Surface freezing is used, for example, to freeze cold cuts. The meat surface is frozen making it easy to cut up and limiting drip loss.
• Individually Quick Freezing (IQF) is used to freeze relatively small foods, making them easily proportionable. This way the product can be evenly coated with herbs or sauces. This technique is mainly used in the preparation of TV dinners, grated cheese, meatballs, vegetables, potato products, etc.
• Deepfreezing food products such as bake-off products, TV dinners, etc.
• Cryogenic grinding is a process in which the product is frozen, making it more fragile and easier to grind. Traditional grinding processes generate heat, causing certain foodstuffs to melt or evaporate. Cryogenic grinding on the other hand, prevents a loss in flavor and aroma, and provides a more even grinding. This technique is used to grind herbs, meat, powders, etc.
• Cryogenic cooling is used to speed up the production process. It is used to cool pastry, filling, dough, and flower. It is also a cooling method for foods that need to be packed immediately, multi-layer products, and it is also used as a subcooling method for putting on ice cream toppings, etc.

SnowCool^®

ACP has developed a snow generator with unique features to cool foods to a predetermined temperature: The SnowCool^®. The SnowCool^® offers the following advantages:

• Rapid cooling of foods, preserving their flavor and aroma.
• Foods are cooled uniformly. The SnowCool^®'s unique design prevents snow crystals from entangling; resulting in evenly outed, extremely fine snow. This way the products are cooled gradually and uniformly, which prevents cracks from forming on the product 's surface.
• Cut out for fragile foods such as potato chips, etc.
• Ideal for both packed and unpacked products CO₂ snow sublimates, leaving no residue.
• Increased overall efficiency thanks to the unique SnowCool^® technology.
• Space-saving Because of its limited size, the SnowCool^® can be installed directly above a food conveyor belt.
• Only a small investment. In most cases the SnowCool^® can be installed in an already functioning production line, with only minimal technical interventions.