The increasing number of outbreaks and recalls related to pathogen contamination of low-moisture foods, including spices, have raised concerns about their safety. The WHO has determined that red pepper poses the highest risk of Salmonella contamination. However, there is limited data on Salmonella thermal inactivation kinetics of red chili peppers. Microwave (MW) drying is an energy-efficient technique that can have a significant impact on various quality aspects of red pepper quality. This thesis investigated that the survival of S. Montevideo in red chili peppers decreased with increasing aw and treatment temperature over time (P < 0.05) and the moisture conditions played a key role in accurately describing Salmonella lethality using the log-linear Biglow model. In addition, modeling using non-isothermal temperature conditions has been shown to better describe the lethality of S. Montevideo than its counterpart. For MW drying, higher MW power (240W) resulted in lower Salmonella survival over time (P < 0.05). MW drying achieved similar quality retention to traditional drying technologies, including total phenolic, ABTS value and total capsaicinoids. Overall, the MW drying at 240W was observed to better retain the color properties and acceptable total phenolics and antioxidant capacity. This study is a first step in predicting Salmonella reduction in spices during commercial processing where temperature and air temperature change over time. This study is a first step for the development of an MW drying system to reduce Salmonella contamination levels in dried red chili peppers to reduce the use of traditional decontamination processes and improve the quality retention.
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