Chow Line: Meaning of dates on canned goods varies (for 8/29/10)

August 20, 2010

Most canned goods seem to have dates or codes on the bottom of the can. Are these expiration dates? If so, how do I read the ones that are in code?

Canned goods don't really have expiration dates. Most canned products have a "best if used by" date, after which the quality of the food may deteriorate, but it still would be safe to eat. Other products may have the date that the product was packaged, or a code indicating its packing date. That and other information, such as which plant manufactured the product, can be used to track the item in case of a recall or other problem.

Unfortunately, there's no standard method for dating or coding used by all canned good manufacturers. If you're curious about the products on your pantry shelves, probably the easiest thing to do is to call the company and ask. Almost all companies that produce canned goods put a toll-free number right on the can.

Most canned goods remain safe and retain their quality for several years. According to the U.S. Department of Agriculture's Food Safety and Inspection Service (FSIS), low-acid canned foods such as meat, poultry, fish and most vegetables will keep fine for two to five years; high-acid foods, such as tomatoes, grapefruit and pineapple, have a shorter shelf-life -- about 12 to 18 months. After that time, you may notice deterioration in color, texture or flavor.

A few things to keep in mind:

  • If a can shows any signs of bulging or leaking, throw it away immediately. Bulging indicates the food has the deadly botulinum toxin. The toxin is extremely rare in commercially canned foods, but it's been known to happen. Don't let curiosity or frugality cloud your better judgment -- just get rid of it.
  • Don't let canned foods freeze. The food could expand and break the can's seal, letting microbes in. While few people would put a canned food item in the freezer, a can could roll out of a grocery store bag in your trunk, and if it's in the middle of winter and there's a chance the food inside the can froze, then pitch it.
  • Slight dents in cans aren't unusual and, as long as the can isn't leaking and the product seems fine, it's safe to consume. But steer clear of severely dented cans -- they're not worth the risk.
  • Pay strict attention to "use-by" dates on infant formula and baby food. That ensures the products have retained their nutrients and remain high quality. According to the FSIS, formula stored too long can separate and clog the nipple on a baby bottle.

Chow Line is a service of Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1044, or filipic.3@cfaes.osu.edu.

Editor: This column was reviewed by Julie Kennel, registered dietitian and program specialist for Ohio State University Extension in the Department of Human Nutrition, in the College of Education and Human Ecology.

Author(s): 
Martha Filipic
Source(s): 
Julie Shertzer