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Foodborne intoxication results when a person eats food-containing toxins (poison) produced by pathogens found on the food. Intoxication can also be the result of chemical contamination. Typically symptoms appear quickly within a few hours. Bacteria are of the greatest concern of the biological contaminants. Bacteria are found everywhere and they can reproduce very rapidly if FAT TOM conditions are right.

Food – Most bacteria need nutrients to survive. Temperature controlled food supports the growth of bacteria better than other types of food.

Acidity – Bacteria grow best in food that contains little or no acid on a pH Scale that ranges from 0 to 14.0 acid to alkaline. Bacteria grow right in the middle more rapidly – 4.6pH – 7.5pH.

Temperature – Bacteria grow rapidly between 41°F and 135°F (5°C and 57°C). This range is known as the temperature danger zone. Bacteria growth is limited when food is held above or below the temperature danger zone.

Time – Bacteria need time to grow. The more time bacteria spend in the temperature danger zone, the greater chance they have to grow to unsafe levels. Bacteria doubles every 20 minutes in the TDZ.

Oxygen – Some bacteria need oxygen to grow, while others grow when oxygen isn’t there (ROP).

Moisture – The amount of moisture available in food is called water activity (aw). The aw scale ranges from 0.0 to 1.0. The higher the value, the more available moisture in the food.

FAT TOM conditions

  1. Food

  2. Acidity

  3. Temperature

  4. Time

  5. Oxygen

  6. Moisture