Forced Air Precooling Studies of Perishable Food Products

Abstract

Food products of perishable nature are needed to be preserved from spoiling using the precooling technique. Precooling is the process of cooling fruits and vegetables as soon as possible after the harvest and prior to the transportation over long distances to a cold storage warehouse and marketing. Therefore, an experimental investigation has been carried out to study the temperature variation of different food products viz. apple, papaya and grape during the precooling process. Forced air cooling of food products was done by placing the particular food item inside a 4 m long rectangular air duct of 300 mm x 300 mm section. The temperature of cold air was in a range of 4-5 oC and the air velocity varied from 1.6 m/s to 4.1 m/s. The temperature of food product was measured at different radial locations inside the product. The effect of air velocity on the temperature profile of food product was observed and it has been found that the proper choice of cold air velocity can reduce the cooling time of certain food product up to 33 percent, thus, resulting in the saving of energy.