| 摘要 |
PURPOSE:To prepare an expanded dry food having excellent quality, by freezing the raw material impregnated with a gas and heating the material with microwave dielectric heating, thereby irreversibly expanding the material while keeping the temperature of the material at a low level. CONSTITUTION:The material to be processed is thrown into a pressure-freezing apparatus, N2 gas is introduced into the apparatus with pressure to effect the through impregnation of the gas into the material, and a refrigerant is introduced into the jacket 12. The frozen material is taken out of the apparatus, transferred without delay to a normal-pressure microwave dielectric heating apparatus supplied with dry air, and heated with microwave. Dehumidified dry air is forcibly circulated until the water-content of the material reaches the peak of the irreversible expansion, when the microwave heating is terminated to obtain the objective dried material having an expansion ratio of 100-130%. |
