DEEP FREEZE CONSERVATION OF RASPBERRY

Abstract

After harvesting raspberries are sold directly to the market or going to freeze. Sensory quality of fruits such as color and flavor are the main factors that influence consumer acceptance. The paper analyzes the process of freezing raspberries depending on how and freezing temperatures. The purpose of the freeze is to reduce the temperature of the product as it is economically feasible in an effort to reduce product quality and prevent deterioration in the product. Quick freezing is freezing process in which fast-forwards zone with the maximum degree of ice crystals (region -1 to -5 ° C) and reached the equilibrium (final) temperature of not higher than -18 ° C. Temperature at which it begins to freeze raspberries is -0.9 º C. Freezing is carried out in a strong current of cold air where the heat transfer coefficient of about 58 W/m2K.