本文以盘装的热烫烹饪莴笋为研究对象，对其真空冷却过程中的影响因素以及温度、失重率的变化规律进行研究。结果表明：真空冷却过程中盘装烹饪莴笋的中心和表面位置的温差非常小，不大于1.73 ℃，冷却至10 ℃时盘装莴笋的中心与表面温差仅为0.23 ℃。另外，真空冷却过程中单位质量烹饪莴笋的冷却速率随着冷凝温度的降低、冷却量的增大而增大。其中当冷却量（37.5 kg）增大3倍（150 kg）时，单位质量莴笋冷却时间有效的缩短了46.34%。同时真空冷却也造成烹饪莴笋质量的损失。1%的烹饪莴笋失重率约能带来7℃的温度下降。另外，本文提出一种分段式真空冷却模式，通过实验验证，该冷却模式能够有效地降低能耗，仅为传统真空冷却方式耗能的47.29%。且通过降低冷却过程中最大冷凝负荷，达到降低冷凝系统制冷能力要求。

Effect of vacuum cooling treatment on blanched cooking lettuce in tray was researched in this paper. Results showed that during the vacuum cooling process, the temperature difference between the center and the surface of cooked lettuce in tray was very small, not more than 1.73 ℃, and the temperature difference was only 0.23 ℃ when cooked lettuce temperature reached 10 ℃. In addition, the cooling rate of cooked lettuce per 1 kg increased with the increase of condensation temperature and cooling capacity. When cooling capacity increased from 37.5 kg to 150 kg, the cooling time was effectively shortened by 46.34%. Vacuum cooling also caused weight loss of cooked lettuce, and 1% of weight loss bring about 7 ℃ temperature decline. This research proposed a two-step vacuum cooling mode to effectively reduce energy consumption, which was only 47.29% of energy consumption of traditional vacuum cooling, and also lower condensate system equipment requirements by reducing the maximum condensate load.

广东省天然产物绿色加工与产品安全重点实验室资助项目（2010A060801004）