Clostridium perfringens
Compiled By: Julie A. Albrecht, Ph.D., Associate Professor
The Organism: Clostridium perfringens are anaerobic bacteria that can produce spores. The bacteria can exist as a vegetative cell or in the dormant spore form in food. Thorough cooking (140°F) will kill the vegetative cells, but spores may survive. At temperatures between 70°F and 120°F, the spores can germinate into vegetative cells and produce a toxin. Germination of the spores and outgrowth into vegetative cells occurs in food inadequately refrigerated. Toxin production normally occurs in the intestinal tract.
Sources of the organism:
- Intestinal tracts of animals and humans
- Soil
- Sewage
- Any raw food may contain the spore or bacteria
Associated foods:
- Cooked meat and poultry products
- Roast beef
- Gravy
Microorganism Characteristics: Gram positive spore forming anaerobic rod shaped bacteria that can produce an enterotoxin which is released in the intestine.
Growth conditions:
- Temperature range: 15-55°C (59-131°F)
- Optimum Temperature: 43-47°C (109-117°F)
- pH range: 5-9
- Lowest reported Aw for growth: 0.96
- Salt Tolerance: 5%
The Disease: Perfringens food poisoning causes gastroenteritis from consuming the vegetative cells. A toxin can be produced by the bacteria in the intestinal tract which can also cause a food borne illness.
Symptoms include:
- Abdominal cramps
- Watery diarrhea
- Nausea
Onset time:
- 8-24 hours
Infective Dose:
- Large numbers (>108 cells) of Clostridium perfringens need to be consumed for symptoms of the illness to develop.
Duration of symptoms:
- 24-48 hours
Control:
- Properly cook meat and poultry products.
- Reheat foods to 165°F for 15 seconds.
- Refrigerate foods at 41°F or below. Foods must reach 41°F within 4 hours.
- Proper cooling techniques are necessary to prevent spore germination.