What is pressure difference precooling?

pressure difference pre-cooling, or forced ventilation cooling, is a pre-cooling technology widely used in fruits, vegetables or cut flowers. The cooling method is to force cold air into the packaging box and make it directly contact with the products. Its principle is to make the pressure difference between the two sides of the packaging box by using the suction fan, so that the cold air enters the packaging box from the ventilation hole on one side and comes out from the ventilation hole on the other side, and at the same time, the tropical air in the box is taken away.