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ARS Home » Northeast Area » Wyndmoor, Pennsylvania » Eastern Regional Research Center » Microbial and Chemical Food Safety » Research » Publications at this Location » Publication #366861

Research Project: Data Acquisition, Development of Predictive Models for Food Safety and their Associated Use in International Pathogen Modeling and Microbial Databases

Location: Microbial and Chemical Food Safety

Title: Thermal inactivation of bacillus cereus spores during cooking of rice to ensure safety of boudin

item Juneja, Vijay

Submitted to: Food Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/2019
Publication Date: 3/9/2020
Citation: Juneja, V.K., Hwang, C., Mishra, A., Taylor, T.M. 2020. Thermal inactivation of bacillus cereus spores during cooking of rice to ensure safety of boudin. Food Microbiology. 122.

Interpretive Summary: Toxin produced by Bacillus cereus in boudin (sausage-like) products, rice fully cooked prior to blending with meat and spices, has been implicated in foodborne illness outbreaks. Therefore, we determined the time and temperature required to destroy spores of B. cereus in order to provide an adequate degree of protection against survival of this pathogen. Our findings indicated that a heat treatment at 99C for 44.4 min would kill 10,000 B. cereus spores in rice. Thermal death time values determined can be used for estimating heat treatment required at any temperature for destruction of this pathogen in cooked rice. This information will be of immediate use to the consumers and to the retail food service industry and regulatory agencies to ensure the safety of boudin.

Technical Abstract: The heat resistance of a four-stain mixture of Bacillus cereus was determined in rice. Bags containing inoculated rice samples with hot water were submerged in a temperature-controlled water bath and held at 90.5, 95, or 99 deg.C for predetermined lengths of time. Surviving spore population were enumerated by plating on mannitol egg yolk polymyxin agar. Survivor curves were fitted to linear and Weibull models using the USDA Integrated Pathogen Modeling Program (IPMP) 2013 software. While both models provided good fit to the data, Weibull model was relatively better since root mean square error values were lower (< 0.32). The time durations to achieve a 4-log reduction were 256.26, 138.81 and 44.38 min at 90.5 deg C, 95 deg.C, and 99 deg.C, respectively. Thermal death time values reported in this study will assist food processors to design lethality processes for the manufacture of foods incorporating cooked rice, such as boudin.