The vaccum cooling process starts with the palletized product being loaded into the vacuum cooler either by forklift or automated pallet loading systems. Once loaded, the vacuum cooling systems starts to evacuate the air from the vacuum chamber. The reduction in temperature via vacuum cooling is achieved by rapid evaporation of water when the atmospheric pressure inside the chamber is lowered to the desire level by the vacuum pump.
The more surface area that the product has, compared to its weight, the greater the amount of heat that can be dissipated at a rapid rate. This means that vacuum cooling is an excellent way to cool products such as leafy vegetables and mushrooms. After some of the moisture in the product is pulled from the product and changed into vapour, the refrigeration coils pull the heat laden vapour away from the product and re-condenses it.
This allows more heat to be pulled out of the product while protecting the vacuum pump of the vacuum cooling system. When the desired temperature is achieved, the vacuum cooler system will automatically re-pressurize the vacuum chamber and allow the product to be removed. Moisture loss, resulting in weight loss of the product, can be reduced by using an integrated water system to spray cold and clean water over the product.