Refrigeration Applications: Vacuum Cooling Of Vegetables and Flowers PDF

Vacuum cooling has been successfully used to cool vegetables and flowers since the 1950s. Produce or flowers that contain free water can be cooled by subjecting them to a deep vacuum. The vacuum must be controlled at 4.5 mm Hg Absolute (600 Pa) to 5.0 mm HgA (667 Pa) (the freezing point of water is at 4.6 mm HgA (613 Pa), i.e., 32°F [0°C]). Another point for reference is 7.6 mm HgA (1013 Pa), i.e., 45°F (7°C).