Did you know the only food item required by federal law to display an expiration date is infant formula? Other food products that display expiration dates are voluntarily adhering to the labeling system as a way to protect the reputation of them and their products by ensuring consumers eat the food at its best or freshest.
Food expiration dating refers to the last date the food should be used or eaten to enjoy it at its freshest. But how long are foods actually safe to eat after their expiration or “sell by” date? Milk is usually good for a week after the “sell by” date while eggs should last for 3-5 weeks after you bring them home. Meat and seafood should all be used or frozen within two days, and canned goods can last anywhere from 18 months to 5 years! And although foods passed their “expiration” may not taste good, most aren’t hazardous.
In America, more than 90% of people throw away food before it has spoiled, and 40% of the U.S. food supply is discarded–unused–every year, close to $162 billion, because of confusion surrounding food dating.
If an expiration date has passed but the food has been handled and stored properly, it should still be safe to eat until signs of spoilage appear. Signs of spoilage include foul odor, flavor, or texture. Molds, bacteria, and yeasts can all cause food to spoil. There are two types of bacteria that can be found in food: pathogenic bacteria that causes foodborne illness, and spoilage bacteria that changes the chemistry of the food but doesn’t cause illness. When spoilage bacteria has favorable conditions including nutrients, moisture, time and temperature, the bacteria is able to multiply rapidly and affect the quality of the food. Contrary to what most people think, a change in the color of meat or poultry is not an indication of spoilage.
Many consumers do not fully understand what is meant by expiration dates and end up throwing out perfectly edible food. In an effort to reduce food waste, environmental advocacy groups, Grocery Manufacturers Association, and the Food Marketing Institute are pushing food manufacturers to use only “best if used by” dates which would go on most foods and “use by” dates which would go on foods that become less safe as they age.
Manufacturers determine the “use by” dates for optimal freshness by conducting microbial challenge studies where a specific pathogen is added to the food. The food is then stored in conditions similar to those it would experience in transportation, storage, store, and a consumer’s home. The food is tested at various times to determine the point at which the food’s safety is compromised. Based on this type of study, manufacturers can then label their product with a “use by” date that ensure the product would be consumed long before its safety is compromised. Most companies set the date even earlier than tests determined as a precaution.
Mathematical modeling tools are another option for determining the dates. In this case a company can enter specific product information and based off of previous challenge studies, a calculator can estimate the products “use by” and expiration dates.
Similar to a challenge study, a static test may also be done to determine dates. Products are stored for extended amounts of time under conditions similar to those it would experience in transport, storage, etc., but no microorganisms are added. The product is again sampled periodically to check quality and safety.
To ensure the safety and extend the life of the food items, the U.S. Department of Agriculture Food Safety and Inspection Services recommend the following:
- Don’t purchase items after the expiration date
- Refrigerate perishable items immediately and freeze them if you won’t use them before the “use by” date
- Follow the safe use and handling instructions on products
- Keep food chilled between 41 and 140 degrees Fahrenheit
If you are a food manufacturer who needs food expiration date testing, shelf-life testing, or other food microbiology testing, submit a food expiration or stability request on our website, or call us toll-free at 1-855-377-6821
The following are recent food test requests we have received and helped facilitate:
- Food Laboratory needed for nutritional bar testing of nutritional bars past expiration date.
- University PhD student working with cereal grain supplemented with soy flour needs food laboratory for expiration stability studies on shelf life of the product for at least one year and analysis will be conducted at interval (once or twice a month). These analysis will include proximate composition,microbial load and identification,functional properties etc.I will also like to participate to know how the analysis are conducted for some months.
- Food Laboratory needed for stability testing of soup to determine expiration date.
- Analytical Food Laboratory needed for testing; need nutritional breakdown, vitamin mineral breakdown, shelf-life/expiration. This bar will be labeled as gluten free, dairy free, cholesterol free, high in fibre, good source of protein, kosher. Will need confirmation of the above. Weight of the bar.
- USA Food Analytical Chemistry Laboratory needed for stability testing, nutritional testing, nutritional values, and test longevity to determine expiration time.
- FDA Food laboratory needed for testing a bottled water for impurities, content, chemicals, plastic toxicity and the expiration date.
- Food Stability and expiration dating testing. Cause of spoilage investigation. Identification and Reformulation testing. Food Drug residue contamination testing.
- Plus more!