Microwave processing has been a promising technology in improving quality and ensuring microbial safety of food products, while non-thermal effects of microwave is in controversy. The objective of this study was to investigate the non-thermal effects of microwave electromagnetic (EM) fields on Clostridium Sporogenes (surrogate of Clostridium botulinum) inoculated in salmon fillets using same time-temperature profiles method. The inoculated salmon fillets were processed by a single-mode pilot microwave processing system with different radiation time (2, 3 and 4 min) and holding time (0, 2 and 4 min). Corresponding water bath treatments were designed for each microwave processing to obtain matching time-temperature profiles. Results showed that the same time-temperature profiles method was successfully achieved to evaluate the microwave non-thermal effects in salmon fillets. With equal or lower thermal lethality value, microwave processing brought significantly higher (P < 0.05) reduction values than water bath treatment. This determined the non-thermal effects of microwave EM fields. And the non-thermal effects increased with longer microwave radiation time and was intensified by higher temperature. However, the following holding section will weaken the additional inactivation efficiency of microwave non-thermal effects. Results suggested that microwave processing could provide better bacteria control with lower thermal processing level.

微波处理一直是提高食品质量和确保食品微生物安全的一项有前途的技术，而微波的非热效应一直存在争议。这项研究的目的是研究微波电磁（EM）场对产孢梭菌（肉毒梭菌的替代物）的非热效应）使用相同的时间-温度曲线方法接种到鲑鱼片中。接种的鲑鱼片用单模中试微波处理系统处理，辐射时间（分别为2、3和4分钟）和保持时间（0、2和4分钟）不同。针对每个微波处理设计相应的水浴处理，以获得匹配的时间-温度曲线。结果表明，成功地采用了相同的时间-温度曲线方法来评估鲑鱼片中的微波非热效应。具有相等或更低的热值致死，微波处理带来显著更高（P <0.05）比水浴处理的还原值。这确定了微波电磁场的非热效应。随着微波辐射时间的延长，非热效应增加，而随着温度的升高，非热效应会增强。然而，随后的保持部分将削弱微波非热效应的额外灭活效率。结果表明，微波处理能够以较低的热处理水平提供更好的细菌控制。