Co-Authors:
Haas, E., Department of Environmental Engineering, Agricultural Engineering Institute, ARO, Bet Dagan, Israel
Gur, G., Department of Environmental Engineering, Agricultural Engineering Institute, ARO, Bet Dagan, Israel, Agrexco Export Company, 20 Ha'arba'ah Street, Tel Aviv, Israel
Abstract:
Commercial-scale experiments carried out during the last five years have shown that the cooling time of a head of lettuce, wrapped in PVC film and packed in a carton, can vary from 25 to 65 min, depending on the design of the vacuum installation. Experiments were, therefore, carried out with a commercial four pallet vacuum cooler, provided in accordance with the requirements of the Agricultural Engineering Institute, with three vacuum pumps and two compressors. The influence of pumping speed, cooling unit capacity and initial temperature on the cooling time and on the final temperature of lettuce leaves and butts was investigated. The results were compared with the cooling rate obtained with other vacuum cooling installations. Design data are proposed. © 1987.