Abstract:The relationship are discussed, between the sublimation drying coefficient and the mode of pre freezing, pre-freezing temperature, material thickness, heating temperature, pressure of drying chamber. Tests were performed using single factor test method. The sublimation drying coefficient of materials was measured with different thickness and pressure under heating temperature 80 ℃, using slow pre-freezing method in the temperature -30 ℃ on the premise that free water sublimation entirely. The results were fitting by software Origin 9.0 and established sublimation drying coefficient query database using VB language. Therefore, the sublimation drying coefficient database of cooked beef slice was set up on the heating temperature 80 ℃ and extended the drying dynamic prediction model of sublimation. The results of verification tests showed that the absolute error of material center temperature between predicted value and measured value less than 5 ℃; The relative error of moisture ratio between predicted value and measured value within 10%. The expanded prediction model could be used to predict the material center temperature and moisture content during drying freeze-dried cooked beef slice within chamber pressure 20~120 Pa and material thickness 6~30 mm.