Overview on Canned Goods
Canned goods consist of almost any type of food that is canned in liquid (dry packed foods not included), and these are commercially available in glass jars with lids, metal cans, or special metal-Mylar®-type pouches.
Canning is a high-heat process that pra
ctically renders the food sterile, such that it can actually be kept at an almost indefinite shelf life when maintained at moderate temperatures (75° F and below).
Food safety therefore, is not an issue in products well-kept on the shelf or in the pantry for long periods of time except that they may have some variation in quality, such as a change of color and texture.
Aside from the convenience in the preservation of food, canned foods are considered safe alternatives to fresh and frozen foods especially when their contents meet dietary standards and have little or no preservatives.
Commercially canned foods are usually better than home canned food because of the special knowledge and equipment used. Furthermore, improper processing of food at home may lead to Clostridium botulinum food poisoning.
Shelf Life of Canned Goods
According to food safety specialist Brian A. Nummer, Ph.D., unopened home canned foods have a shelf life of one year to two years while commercially canned foods should be able to retain their best quality until the expiration code date on the can. Expiration date is usually two to five years from the date of manufacture.
Commercially canned foods in metal or jars usually remain safe for consumption as long as the seal has not been broken. Foods sealed in metal-Mylar-type pouches (such as U.S. Military MRE’s or Meal, Ready to Eat), which typically have a best-if-used by date on them have been known to keep for as long as eight to ten years. However, storage for longer than 10 years is not recommended.
High acid foods usually have a shorter shelf life than low acid foods. There are types of foods that may be kept only until its recommended "use-by" date, while others may be kept almost indefinitely. Therefore, it is helpful to know about how some manufacturers code their products.
Many canned products now have a "For best quality use by" date or “Consume by” date stamped on the top or bottom of the can. On the other hand, expiration dates are uncommonly found on canned products.
Many manufacturers record day, month and year of production, while other companies cite only the year. Consumers usually find these codes printed on the top or bottom of the can. However, some manufacturers print other numbers that reference the specific plant manufacturing or product information, which are not useful to consumers.
Unless individuals find easy-to-understand information, consumers may be confused by codes that read like “A195” on top of a can, which may actually refer to July 14, 1999, which is the date product was manufactured (A=1999, July 14 is the 195th day of the year). Some codes may have four to ten digits, while others may also include letters.
Consumers may contact the food manufacturer directly or use their 1-800 numbers to clarify product code questions and consumer inquiries.
Shelf Life Recommendations
When understanding product codes become too complicated for consumers who don’t have the time to scrutinize each product he/she buys off supermarket shelves, it may be more practical to rely on recommendations for food storage. Here are some examples:
Recommended Shelf Life of Canned Foods (months)
- Canned Vegetables, 24 – 48
- Canned Baked Beans, 24 – 36
- Canned Ragu Spaghetti Sauce, Use By Date
- Canned Fruit Juices, 6
- Canned Meat, Chicken, 36
- Canned Soup, Expiration Date
- Canned Tomatoes, 36+
- Spam, Chili, Ham Chunks, Indefinite
- Canned Tuna, Fish & Seafood, 5 years
- Canned Cranberry Sauce, Expiration Date
- Canned Fruits, 36+
- Canned Fruit Pie Fillings, 24 – 36
- Canned Baby foods, 12
- Canned Tomato Sauce, 12
- Condensed, evaporated and dry milk, 12 – 23
Prolonging Shelf Life of Canned Goods
Here are some reminders for prolonging the shelf life of processed foods in cans:
- Canned foods should be stored in a cool, dry area below 85°F (optimum 50°F to 70°F). Canned goods stored in high humidity areas may result in rusty, leaky cans.
- Store canned foods in a cool, dark, dry space away from furnaces, pipes, and places where temperatures may change like un-insulated attics.
- Do not allow sealed cans or glass jars to freeze as this may change food textures, and lead to rusting, bursting cans, and broken seals.
- Avoid leaving metal cans on the floor, especially bare concrete which will allow moisture and encourage rusting.
Other Safety Precautions
- Always use the FIFO (First-in, first-out) principle, meaning one should use the oldest cans first.
- Discard any badly dented, bulging, rusty, or leaky cans or jars that may have broken seals.
- If one has opened a can with a strange odor or appearance discard contents immediately and do not taste.
- When using older canned foods, boil the food for 10 minutes before tasting. Discard if there is a strange flavor.
- Canned foods may last between a day to a week after opening, depending on the type of food.
Jahner, Brandon and Nummer, Brian A., "Canned Goods, UtahState University Cooperative Extension, https://extension.usu.edu/foodstorage/htm/canned-goods
Boyer, Renee and McKinney, Julie, "Food Storage Guidelines for Consumers, Virginia Cooperative Extension, VT.edu, https://pubs.ext.vt.edu/348/348-960/348-960.html
Author unknown, "Canned Food, Shelf Life," Foodreference.com, https://www.foodreference.com/html/tcannedfoodshelflife.html