2014 Volume 20 Issue 1 Pages 43-49
Rapidity is the biggest advantage of vacuum cooling in the food industry, especially for cooked meat. However, the largest volumetric displacement does not guarantee the best temperature uniformity because the structure of the food can affect the mechanisms of heat and mass transfer in food during the vacuum cooling process. Because the temperature uniformity is one of the most important factors in the cooling effect, it is necessary to achieve a uniform temperature distribution across the portion of food by choosing the best evacuation scheme. In this paper, the volumetric displacement was varied with the pressure to conduct a vacuum cooling experiment for heated ham. The results were evaluated by measuring the real-time temperature distribution on the ham section using a sensitive infrared thermal imaging system. The results indicated that properly varying the volumetric displacement during the cooling process can not only uniformize the temperature distribution across the ham section but that it can also reduce both the weight loss and energy consumption. Consequently, a reasonable varying volumetric displacement can help improve the vacuum cooling effect.
