PROCESS FOR VACUUM PRECOOLING OF VEGETABLE, OR THE LIKE AND APPARATUS THEREFOR

摘要

PURPOSE:To generate cracks in a thin-walled part of a cold-reserving box placed in a vacuum chamber and containing an object to be reserved in cold state, to cool the space in the box through the cracks and to close the cracks under atmospheric pressure, by forming a thin-walled part for crack-generation at a proper part of a cold-reserving box for vacuum precooling. CONSTITUTION:A thin-walled part 6 for crack generation is formed at a proper part of a main body 2 of a vessel made of foamed synthetic resin and used in vacuum-precooling and/or a lid 3 attached to the main body in a manner to keep air-tight state. An object to be reserved in cold state is put into the vacuum cold-reserving box 1 having the above structure and the box 1 is placed in a vacuum chamber 9. Cracks are generated in the cold-reserving box according to the deaeration and evacuation of the vacuum chamber 9 and the cold- reserving chamber 1 is evacuated through the cracks to cool the object to be cooled. The cracks are closed by atmospheric pressure when the cold-reserving box is placed under atmospheric pressure. The cooled state in the cold-reserving box can be maintained while keeping the air-tight state and the object is kept in fresh state over a long period.