Laboratory Testing to Determine if a Food is Shelf Stable
What does “TCS” stand for?
TCS stands for Time/Temperature Control for Safety and means that a food requires temperature control or needs to be consumed within a limited time to limit pathogenic microorganism growth or toxin formation that can make people sick.
Typically TCS foods include in whole or in part an animal product that is raw or cooked, plant food that is cooked or contains raw seed sprouts, cut melons, cut leafy greens, cut tomatoes, and/or garlic in oil mixtures.
Some foods, such as air-cooled hard-boiled eggs with the shell intact, or raw shelled eggs that have been pasteurized are not considered TCS foods. Shelf-stable foods in intact hermetically sealed containers are also excluded.
What is needed to verify a recipe or food is not TCS?
A food that is typically a TCS food may be rendered non-hazardous if its acidity and/or water activity (Aw) has been modified. Sometimes ingredients are added to lower a food’s pH or acidity. Sometimes a food is dried, depriving bacteria of the moisture needed to survive and grow in the food.
A sample of the food product needs to be sent to a certified laboratory to determine if the pH and water activity (Aw) render it a non-TCS food. The following tables provide the parameters used to make that determination:
|Table A. Interaction of pH and AW for control of spores in FOOD heat-treated
to destroy vegetative cells and subsequently PACKAGED.
|4.6 or less||>4.6-5.0||>5.0|
|≤0.92||Non-PHF*/Non TCS FOOD**||Non-PHF /Non TCS FOOD||Non-PHF /Non TCS FOOD|
|>0.92-.95||Non-PHF /Non TCS FOOD||Non-PHF /Non TCS FOOD||PA***|
|>0.95||Non-PHF /Non TCS FOOD||PA||PA|
|Table B. Interaction of pH and AW for control of vegetative cells and spores in
FOOD not heat-treated or heat-treated but not PACKAGED.
|<4.2||4.2 – 4.6||>4.6-5.0||>5.0|
|<0.88||Non-PHF */Non TCS FOOD**||Non-PHF /Non TCS FOOD||Non-PHF /Non TCS FOOD||Non-PHF /Non TCS FOOD|
|0.88 – 0.90||Non-PHF /Non TCS FOOD||Non-PHF /Non TCS FOOD||Non-PHF /Non TCS FOOD||PA***|
|>0.90-0.92||Non-PHF /Non TCS FOOD||Non-PHF /Non TCS FOOD||PA||PA|
|>0.92||Non-PHF /Non TCS FOOD||PA||PA||PA|
|Tables A & B: *PHF means POTENTIALLY HAZARDOUS FOOD, ** TCS FOOD means TIME/TEMPERATURE CONTROL FOR FOOD SAFETY, ***PA means PRODUCT ASSESSMENT required|
PA stands for Product Assessment Required. In these cases, the product must be tested by a certified lab.
Testing must be done a minimum of annually for a given recipe and whenever the ingredients or amounts of ingredients change. All initial test results must be sent to the Health Authority for review and verification. Results of annual tests on the same product/recipe must be kept on site for Health Authority review.
If you have any questions, please contact the Southern Nevada Health District at 702-759-1110.
Phone: (702) 759-0588
Updated on: October 10, 2018