大米脉冲微波杀虫防霉工艺优化
Optimal technology of preventing rice storage pests and mildew by pulsed microwave

以大米为原料，采用脉冲微波宽度、微波剂量、微波时间、脉冲间歇时间等单因素试验，研究脉冲微波对大米害虫米象(Sitophilus oryzae)和寄生曲霉(Aspergillus parasiticus)致死率、米温、大米的碎米率和爆腰率及其感官品质的影响。结果表明：随着脉冲微波强度的增加，米象和寄生曲霉致死率明显升高，虫卵孵化率显著降低，感官品质变化不大，米温逐渐升高，碎米率和爆腰率有所升高。通过正交试验确定大米杀虫防霉最优工艺为：脉冲微波剂量7.5 W/g、脉冲宽度300 ms、间歇时间50 ms、脉冲微波总时间30 s，此时害虫和霉菌致死率分别可达100.0%、83.2%，米温53.8 ℃，碎米率和爆腰率比未处理的样品增加1.2%和1.5%，感官评分7.3分。
Effects of pulsed microwave on fatality rate of rice weevil and Aspergillus parasiticus and rice quality (rice temperature,the ratio of broken-rice and cracked-rice,and sensory quality) were investigated to provide a suitable microwave processing technology for rice storage.Based on the single factor experiments of width,dose,total time and intermittent time of microwave,the fatality rate of rice weevil and Aspergillus parasiticus increased dramatically with the increase of irradiation intensity.Meanwhile,the rice temperature increased gradually,weevil hatchability declined dramatically,the ratio of broken-rice and cracked-rice increased slightly with no obvious changes in overall sensory.By orthogonal test,the optimal pulsed microwave condition was found to be pulsed microwave dose of 7.5 W/g,pulse width of 300 ms,interval time of 50 ms,the total processing time of 30 s.Under the optimal condition,the fatality rate of rice weevil and Aspergillus parasiticus was 100.0% and 83.2%,respectively.The rice temperature was 53.8℃.The ratio of broken-rice and cracked-rice increased by 1.2% and 1.5%,respectively.The sensory score was 7.3.