Process optimization of microwave sterilization for Aspergillus niger from rice

In order to explore the killing effects of microwave treatment on molds from rice, response surface methodology was used to optimize process of microwave sterilization Aspergillus niger from rice. Effect of microwave power, microwave time, and mould suspension volume on log-periodic reduction of spores of Aspergillus niger from rice were investigated, and corresponding regression equation was established. Results showed that optimum sterilization conditions were as follows:microwave power of 231 W, microwave time of4 min, and mould suspension volume of 97 m L. Under these conditions, log-periodic reduction of spores of Aspergillus niger was 4.8920±0.0882, relative error between determined and predicted value of log-periodic reduction of spores was 4.37%. Compared with water-bath heating treatment, effect of microwave sterilization was 8.5 times as much.