Food Science

The Mailbox: How to read food labels for safety and freshness

By Teri Mena

With the holidays fast-approaching, this is a good time to review the meanings of dates stamped on the packaging of different foods, the “sell by” date and “best if used by” date, which can be confusing. We’re also including guidelines on how to store certain foods safely and how long to keep specific foods.

Food dating

According to the Food Safety and Inspection Service division of the United States Department of Agriculture, the United States has no universally approved system for dating food. There is no federal regulation requiring food dating, with the exception of infant formula and some baby food. If a manufacturer uses a food date, it must include the month and day. If the product is frozen or shelf-stable (such as mayonnaise, mustard, peanut butter), it must also include the year. Additionally, the meaning of that date must be explained, for example: Best if used by 3-20-15.

▪  Sell by: This date is for the store selling the product and tells them how long the item should be displayed. It’s a good idea, as a consumer, to check this date as well, so products on the shelf after the “sell by” date are not inadvertently purchased.

▪ Best if used by (or best if used before): Food consumed by this date will be at maximum quality (flavor, color and texture). Food eaten after this date may be edible, but the quality is not guaranteed. This is not a safety date.

▪ Use by: This date is the last day the product is at its peak in quality. This is not a safety date. This date is set by the manufacturer.

▪ Expires on: Do not consume the product after this date.

In the can

All canned food must have packing codes (a series of letters and/or numbers) so the manufacturer can track, rotate and find a product if it is recalled. The consumer is not meant to decipher these codes; they are not related to food dating. Most canned foods carry “Best if Used By” dates. Always store canned foods in a cool, dry place.

Discard the following:

▪ Any cans that are rusted, bulging, leaking or badly dented. If the contents spurt out when opened, discard.

▪ Any food that looks or smells bad, including canned food and fish.

▪ Any food with an expiration date that has passed.

Once a perishable item is frozen, regardless of packaging date, it is safe indefinitely. The quality, however, may be compromised.

For more food dating information and charts on food storage, go to; under “topics” look for “fact sheets” and “food labeling.”

Another helpful website on how long to keep specific foods is Following is a short list of items from this Website to be used as a general guide. These recommendations are based on food that has been properly handled and stored.

▪ Milk: One week after “sell by” date

▪  Butter: One month after “sell by” date

▪  Eggs: Three to five weeks after “sell by” date. Refrigerate in the original carton on a shelf, in the back of the refrigerator, not in the door.

▪  Cheddar cheese (commercially packaged), not opened: One week after date on package, opened: five to seven days after date on package

▪  Sugar: Keeps indefinitely

▪  All-purpose flour (not whole wheat), opened or not: A year in the pantry, two if refrigerated

▪  Pasta (uncooked): Three years

▪  Rice: Keeps indefinitely (brown rice – three to six months)

▪  Breakfast cereal: Not opened, a year; opened; two to three months

▪  Cake mix not opened: 12 to 18 months

▪  Fresh meat: Cook or freeze within three to five days of purchase

▪  Ground meat: Cook or freeze within one to two days of purchase

▪ Fresh poultry: Cook or freeze within 1 to 2 days of purchase

▪ Fish: Cook or freeze within one to two days of purchase

▪ Canned: Low acid (meat, most vegetables), two to five years; high acid (tomatoes, grapefruit), 12 to 18 months

▪ Peanut butter: Not opened, two years; opened, three months

▪ Soda in can or glass bottle: Nine months after date on package

▪ Soda in plastic bottle or diet soda: Three months after date on package



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