While there is no standard system for coding on canned foods, many companies use similar codes to track their products. Learning to read the most commonly used codes that refer to dates helps ensure your canned foods are fresh and safe to eat. Some canned foods include a noncoded "use by" date stamped on the can or label. For those that don't, you can often find a coded date stamped on the top or bottom of the can.
Look at the first number or letter of the code. Numbers 1 through 9 often represent the months January through September, in order. The letter "O" usually stands for October, "N" represents November and "D" stands for December on many cans. Some companies list the month after the date, so look elsewhere in the code for letters as well.
Match letters other than "O" and "N" with months by assigning each month, January through December, a letter from "A" to "L" in alphabetical order. Some companies use this form of coding to represent months. Be careful when interpreting these codes if you need to be sure about the month. "D" could stand for April or December, depending on the coding system used by the manufacturer.
Decipher numbers to determine the day and year. Many companies use a two-digit number following the first number of the code for the date and a one-digit number for the year. The year number is usually the last number of the year. For example, 2011 would have a year number of 1.
Determine the Julian date that would correspond with the code if the numbers don't make sense in the context of month, date and year, or if you know the manufacturer uses Julian dates in its codes. The Julian date is the day of the year. For example, Jan. 1 would be 1 and Feb. 10 would be 41 if a Julian date is used.
Check your canned food products for a toll-free number or website if you’re not sure about the code on the can or the date by which you should use the product. Some companies mix up the date format by listing the year or the date first instead of the month, so if you’re in doubt, it’s best to ask the source. Most manufacturers offer a telephone number or website for consumers with questions about the expiration dates of their products. Most canned foods are safe to use for two years from the date of purchase, even if you can’t read the code on the can and can’t find a “use by” date on the product. Store your canned food at a moderate temperature to ensure freshness. The Canned Food Alliance recommends storage temperatures no higher than 75 degrees Fahrenheit.