关键词: 营养冲调粥, 流化床干燥, 干燥特性, 动力学模型

Abstract: An experimental study was conducted to investigate the drying characteristics of nutritious reconstituted porridge (prepared from a mixture of corn, red bean, buckwheat, oats and millet (3.5:3.0:2.0:0.7:0.8, m/m) with added water by twin screw extrusion) on a fluidized bed dryer. The effects of airflow rate, inlet air temperature and water addition on the dry basis moisture content and drying rate of nutritious reconstituted porridge were explored. The water loss characteristics during the drying process were obtained. Based on the experimental data, a kinetic model was established, and it was statistically tested. The results showed that the Page model was the best model for describing the fluidized bed drying of nutritious reconstituted porridge, and the fitting equation was ln(?ln MR) = ?4.064 63 + 0.014 14T + 0.069 85v + 0.327 5H + (0.570 96 + 0.000 976 25T ? 0.009 68v ? 0.265 5H)ln t, where T was inlet air temperature (℃), v was airflow rate (m/s), and H was the amount of water addition (%). This equation could better describe the drying process and accurately predict the dry basis moisture content and drying rate at each of its stages.

Key words: nutritional reconstituted porridge, fluidized bed drying, drying characteristics, kinetic model