Page was A Dead aloud 1 Adet EXAMPLE 7.1. Heat energy in air drying • A food containing 80% water is to be dried at 100°C down to moisture content of 10%. If the initial temperature of the food is 21°C, calculate the quantity of heat energy required per unit weight of the original material, for drying under atmospheric pressure. The latent heat of vaporization of water at 100°C and at standard atmospheric pressure is 2257 kJ kg. The specific heat capacity of the food is 3.8 kJ kg 1°C-1 and of water is 4.186 kJ kg! °C. Find also the energy requirement/kg water removed.