PH

Intrinsic factor - can be inhibitory to microorganisms - high acid foods (pH below 4.6): fruits, fruit juices, fermented fruits, salad dressing - low acid foods (pH above 4.6): vegetables, red meats, poultry, sea foods, milk, soups - foods with pH >= 4.6 are potentially hazardous: moist, nutrient rich, support rapid microbial growth - pH 6.6-7.5 best for microbial growth - most foodborne bacteria will not grow at pH < 4.6