工业用微波柜复热冷链盒装米饭的研究

Research on Reheating Packed Rice of Cold Distribution with Industrial Microwave Equipment

冷链盒装米饭是指米饭蒸煮后,经一定方式将米饭中心温度冷却至10℃以下,并在加工、运输、贮存和销售等后续处理中始终保持在10℃以下,食用前须加热至米饭中心温度高于70℃。研究工业用微波柜复热冷链盒装米饭过程中,米饭中心温度、质量损失率、感官评定及菌落总数的变化。结果表明,微波功率密度越大,单盒米饭中心温度升温速率越高,呈现良好的线性关系;米饭中心温度升温速率常数跟米饭盒数呈现良好的指数关系。在微波过程中,米饭的质量损失率随米饭中心温度呈指数上升趋势。以微波功率密度20 W/g处理单盒米饭,微波30 s时米饭的感官评定分数最高,此时米饭温度89.0℃;米饭中心温度复热至94.7℃时,米饭菌落总数降低1个数量级。

Packed rice of cold distribution is that the central temperature of rice is cooled to 10 ℃ by some way after cooked, and it is always kept below 10 ℃ during the subsequent processing. Before eating, the central temperature of rice should be reheated higher than 70 ℃. To find the change of packed rice of cold distribution during the reheating with industrial microwave equipment, the center temperature, weight-loss ratio, sensory evaluation and total member of colony of rice are determined. The results show that the heating rate of the center temperature of rice （single box） shows a good linear relationship with the microwave power density, and the center temperature of rice （over box） shows a good exponential relationship with the quantity of rice boxes. During the process of microwave, the weight-loss ratio and center temperature of rice shows a good exponential relationship. Reheating rice with the microwave power density of 20 W/g, when the processing time is about 30 s （89.0 ℃） , and the sensory evaluation of rice is the most highest. When the center temperature of rice is 94.7℃, total member of colony of rice is decreased by one order.