Are you cereus?

Our usual evening schedule is dinner, a bit of hockey on TV and then wind the kids down with books or a bath before bed. Sometimes it takes 20 minutes to get them to sleep, sometimes 2 hrs. After losing a few meals by leaving our dinner leftovers out for too long due to an extended bedtime routine, we’re now in the habit of refrigerating extras before we sit down to eat.

Tonight’s risotto was packed up and chilling to avoid growing Bacillus cereus (linked to rice dishes 50 per cent of the time).

Bacillus cereus is sort of a fun pathogen (except for those who are affected by it): Two different toxic proteins can be produced by the bacteria as it grows. The one that causes vomit is preformed in food, the one that causes diarrhea is released by the bacteria as it grows in the body.

Turns out that toxin stability in food also plays a part in illnesses.

Effect of temperatures on the growth, toxin production, and heat resistance of bacillus cereus in cooked rice
Foodborne Pathogens and Disease. February 2014, 11(2): 133-137. doi:10.1089/fpd.2013.1609
WangJun, DingTian, and OhDeog-Hwan

Bacillus cereus is capable of producing enterotoxin and emetic toxin, and Bacillus foodborne illnesses occur due to the consumption of food contaminated with endospores. The objectives of this study were to investigate the growth and toxin production of B. cereus in cooked rice and to determine the effect of temperature on toxin destruction. Cooked rice inoculated with B. cereus was stored at 15, 25, 35, and 45°C or treated at 80, 90, and 100°C. The results indicated that emetic toxin was produced faster than enterotoxin (which was not detected below 15°C) at all the storage temperatures (15–45°C) during the first 72 h. Emetic toxin persisted at 100°C for 2 h, although enterotoxin was easily to be destroyed by this treatment within 15 min. In addition, B. cereus in cooked rice stored at a warm temperature for a period was not inactivated due to survival of the thermostable endospores. These data indicate that the contaminated cooked rice with B. cereus might present a potential risk to consumers. Results from this study may help enhance the safety of such food, and provide valuable and reliable information for risk assessment and management, associated with the problem of B. cereus in cooked rice.

And from the sort of obvious file, the authors say, “These data indicate that the contaminated cooked rice with B. cereus might present a potential risk to consumers.” Uh huh. It’s not just the data, but the many recorded outbreaks.

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About Ben Chapman

Dr. Ben Chapman is a professor and food safety extension specialist at North Carolina State University. As a teenager, a Saturday afternoon viewing of the classic cable movie, Outbreak, sparked his interest in pathogens and public health. With the goal of less foodborne illness, his group designs, implements, and evaluates food safety strategies, messages, and media from farm-to-fork. Through reality-based research, Chapman investigates behaviors and creates interventions aimed at amateur and professional food handlers, managers, and organizational decision-makers; the gate keepers of safe food. Ben co-hosts a biweekly podcast called Food Safety Talk and tries to further engage folks online through Instagram, Twitter, Facebook, YouTube and, maybe not surprisingly, Pinterest. Follow on Twitter @benjaminchapman.