If your garden is getting as big as mine is, it is time to think about canning. Canning is a great way to preserve all your garden goodies for the whole year or, depending on the product, many years to come. As you add new cans to your supply, you need to check your stock and rotate out the cans that may have spoiled over the years. How do you tell if the can is spoiled? Remember the golden rule of canned goods, when in doubt throw it out. Here are some ways to tell if your canned good is in doubt:
If you see any bulging of the lid on a canned good, throw it out!
If you see signs of corrosion on the lid, throw it out!
If you see that food has seeped out from under the lid, throw it out!
If you see that the food in the jar has bubbles like a soda can that are in motion, throw it out!
If you see that the food is cloudy or mushy like the food in the jar on the right, throw it out!
If the food inside smells bad and not like it's supposed to, throw it out!
If the jar shoots out liquid when you open it, throw it out!
Michael S. Sweeney suggest in his book, Complete Survival Manual, that any canned goods that have been exposed to fire, heat, smoke, fumes, or flood waters be disposed of. Canned goods that are exposed to toxic chemicals may be salvageable but you should wash them and immerse them in a bleach solution (one teaspoon bleach per quart of water) before opening them.
If you do need to dispose of some goods that are canned in jars. Open the lid, discard the product, discard the lid and sanitize the jar. The jar is reusable but you will need a new lid.