Bacillus cereus

Information adapted from The Safer Food Group: Level 3 Food Safety (Supervisor) course

An aerobic, pathogenic bacteria that produces a heat resistant exotoxin (spore forming).

Description:

Bacillus coagulans is one of the good guys – a bacteria that forms the basis of some probiotic foods. Unfortunately, it has less friendly cousin; Bacillus cereus which causes food poisoning.
Bacillus cereus is a soil-dwelling, spore-forming food poisoning bacteria chiefly associated with cooked rice, as well as other starchy foods including pasta and potatoes. If cooked at less than 100°C, bacterial spores survive and germinate, releasing toxins which cause food poisoning.

Source:

Foods affected include rice, pasta, potatoes, cereals, and spices.

It loves inadequate cooking and poor refrigeration and hates good food hygiene practice. The best way to avoid food poisoning from B. cereus is to avoid reheating rice dishes.

FSA guidelines require cooked rice to be chilled/refrigerated and used within 24 hours.

Symptoms:

Nausea, vomiting, abdominal pain and occasionally diarrhoea.

Onset time: 1 – 5 hours
Duration: 12 – 24 hours
Carrier Status: None

Controls:

  • Thorough cooking and rapid cooling of food; typically rice is cooked in boiling water – 100°C – for at least 10 minutes.
  • Following cooking, control bacterial multiplication by the reduction of time in the danger zone after cooking, i.e., control of time and temperature during hot holding, and rapid cooling before storage
  • Refrigerated storage at 5°C or less for no longer than 24 hours
  • Avoid reheating rice dishes if possible – if reheating rice is undertaken ensure recommended FSA cooking temperatures and times are achieved.
  • Take care to prevent cross-contamination