Abstract:With the power density, roasting time, spinning speed of roller and wind speed of microwave as the experimental factors, and the bulk density and roasting color value of coffee beans as the indexes for evaluation, the single factor test and the four-factor four-level (44) orthogonal test were conducted. It was shown by the results of optimization that the optimal technology parameters were: the microwave power density 8 W/g, the roasting time 12 min, the speed of roller 70 r/min, and the wind speed 1.5 m/s. Through experiments, it was confirmed that the bulk density of microwave roasted coffee beans under the optimized technology parameters was 0.286 g/mL, and the baking color value was 32.1. Moreover, with the degree of roasting being dark, no coking occurred in coffee beans and the quality was good. The prediction model of fracture force for coffee bean was obtained by regression fitting, with the determination coefficeint of 0.998 after cerrection, good model fitting, and there is obvious relationship of quadratic regression between fracture force F, bulk density b, and roasting chromatic value C.