Does the Staphylococcus Aureus Toxin Withstand Freezing?

Staphylococcus aureus is a toxin-producing bacterium. Ingestion of food contaminated with the toxin causes Staph aureus food poisoning. According to Ohio State University Family and Consumer Sciences, Staph aureus is the most common cause of foodborne illness. Killing the bacteria does not destroy the disease-causing toxin.

Dose

• Staphylococcus aureus produces an enterotoxin, a poison that causes inflammation of the digestive tract. The FDA reports a toxin dose less than 1.0 microgram in contaminated food produces staphylococcal intoxication symptoms. Such levels are achieved when Staph aureus populations exceed 100,000 per gram of contaminated food.

Sources

• According to Medline Plus, Staph aureus contamination is most common in foods served at room or refrigerator temperature, including custards or cream-filled desserts, salads containing mayonnaise, poultry, eggs and casseroles. Food handlers are the most common cause of contamination.

Management

• Although Staph aureus bacteria grow best at body temperature, Dr. Julie A. Albrecht of the University of Nebraska says they can multiply rapidly in food held at room temperature. According to Albrecht, thorough cooking destroys the bacteria, but the toxin is extremely resistant to heat, freezing and refrigeration. Proper hand washing techniques and sanitation of preparation surfaces and utensils help control contamination. Holding foods at 41 degrees or below slows bacterial growth, thereby limiting toxin production.