Half-cooling time of cabbage stored in a refrigerated room

Abstract

Cabbage heads stored in containers in a high-capacity cooling room were evaluated by the half-cooling times. The temperature of the heads and the surrounding air in their immediate vicinity was measured by a puncture thermometer. The shortest half-cooling times were measured in the immediate vicinity of the evaporator; in contrast, very long half-cooling times were measured in a container on the opposite side of the cooling room. The measured values were longer by one order of magnitude. When cabbage heads are inside the container furthest from the evaporator, without being covered by a layer of stacked containers, then the heat transfer passes directly into the ambient air, thus, the half-cooling times in this container were not the longest. The head cabbage cooling, evaluated by the half-cooling time (in hours) and the end of cooling time (in hours), in the chambers to a storage temperature (0 °C) are directly proportional. The heads in a container 14 m from the evaporator, in the bottom position, but not covered by other containers had a half-cooling time of 194.7 hours, with a total time of 973.5 h, because the air circulating around the container, permanently cooled down the stored heads. The total calculated cooling time will be extended 5.0 times. For the heads in the same position, but 7 m from the evaporator, the heat dissipation at the bottom position was so slow that the half-cooling time was 225 hours, and the total time was 1 125 hours (46.88 days), which was the longest cooling time for the cabbage heads. Kewords: head cabbage; refrigeration; distance of container from evaporator