According to the National Center for Home Preservation…
Properly canned food stored in a cool, dry place will retain optimum eating quality for at least 1 year. Canned food stored in a warm place near hot pipes, a range, a furnace, or in indirect sunlight may lose some of its eating quality in a few weeks or months, depending on the temperature. Dampness may corrode cans or metal lids and cause leakage so the food will spoil.
Does that mean you need to junk your jars’ contents starting month 13?
No, not necessarily. Just like store-bought foods, your properly stored, home canned foods don’t automatically go bad on the 365th day. What it means is that after a year, natural chemical changes can occur which can alter the taste, texture and/or nutritional value of the food.
After the one year mark (and honestly, it’s not a bad idea to do it before then, too!), you should inspect the canned food before you eat it.
Here are some signs your home canned food has spoiled:
- The jar’s lid is not completely sealed.
- There are dried food streaks on the outside of the jar that originate from the top.
- There’s mold in the jar and/or on the inside of the lid.
- The contents smell off.
- The food has changed color.
- The brine or syrup in the jar is opaque or muddy.
- The contents are bubbly.
- The food spurts out of the jar when you open it.
The bottom line:
It’s best to eat all your home canned goodies before the one year mark, but know that there’s a good chance they will be safe longer than their first year.
And remember, when in doubt, throw it out!