Frequently Asked Questions

Q: What does the term "Sell-By" mean on food products?

A: A "Sell-By" date tells the store how long to display the product for sale. You should buy the product before the date expires.

Q: What does the term "Best if Used By (or Before)" mean on food products?

A: A "Best if Used By (or Before)" date is recommended for best flavor or quality.

Q: What does the term "Use-By" mean on food products?

A: A "Use-By" date is the last date recommended for the use of the product while at peak quality. The date has been determined by the manufacturer of the product.

*Remember, once a food item is opened, bacteria go to work on it right away. Therefore, the above dates are not valid once the item is opened.

Q: Am I able to tell if a food is safe or unsafe to eat by the way it looks and smells?

A: Bacteria that ruin the taste of food do so by breaking down the components of the food into compounds they can use for growth. These compounds contribute off-odors and off-flavors that cause texture changes which make foods watery, slimy, etc. Some bacterial compounds that cause illness do so by growing in the body or by producing very specific toxins in the food, or in some cases inside the body. Spoilage organisms usually grow more rapidly than disease-causing (pathogenic) organisms and they produce signs of spoilage that are a warning sign that the product may be close to being unsafe. However, foods containing pathogens may exhibit no signs of them.

Source(s):

Dr. Susan Brewer, Ph.D., University of Illinois, Department of Food Science and Human Nutrition

USDA Fact Sheets "Food Product Dating"

U.S.D.A Food Safety and Inspection Service. 2006. "Basics for Handling Food Safely"

Centers for Disease Control