Acidity and Alkalinity Requirements

---

A discussusion of bacteria pH preferences.....

---

The acidity or alkalinity of a food product is measured by its pH. pH is a chemical term for the measurement of hydrogen ions present.

Foods with a pH of 7.0 are considered to be neutral. Meat, eggs, milk, vegetables, (THE POTENTIALLY HAZARDOUS FOODS) fall within this range. Corn, peas, rice, and certain hybrid fruits and vegetables, such as tomatoes bred for low acidity, can pose a threat of foodborne illness.

As the pH increases (up to 14) the food is said to be alkaline. Foods with a high alkalinity are egg white, soda crackers, and black olives. Bacteria do not readily grow on these foods, but some bacteria are known to grow on alkaline products that contain enough water to support growth.

As the pH decreases (down to 0) the food is said to be acidic. Food with a high acidity level are citrus juices, vinegars, pickled foods, , commercial mayonnaise, and salad dressing. Bacteria do not readily grow on high acid foods, but some bacteria are known to grow on acidic products that contain enough water to support growth.

Return to Table of Contents Return to Hazards