Are My Canning Jars Safe to Use?

As I’ve been spring cleaning my fruit cellar, I’m also taking the time to sort through my hundreds of canning jars as well. Part of the sorting process is deciding whether or not they are safe to use.

Home canning is a great way to preserve home grown food. Canning your own produce ensures that the ingredients are wholesome and is a fantastic way to reduce waste since the glasses are 100% re-useable. But, just like any other tool used in the kitchen, even canning jars wear out over time. At what point are canning jars no longer safe to use? Here are three tell tale signs that your canning jars are no longer safe for canning and ready for the recycling bin .

Chipped rims. Using a knife or bottle opener to lift the seal of a jar of home-canned goodies can lead to tiny nick in the rim. While the nick itself isn’t dangerous, it can prevent a good seal the next time you put up a batch of home canned produce. The easiest way to check for nicks is to run your finger around the edge of the rim. In most cases, it is easier to feel than see.

Too thin. If the jar you are holding feels thin, then it most likely is NOT a canning jar but someone’s old mayonnaise or marinara jar instead. Instead of canning with these jars, toss them in the recycling bin instead. Why? Store jars aren’t safe for home canning because they aren’t heat tempered to withstand rapidly changing temperatures. There’s also the problem of the rim being a bit too small for a lid to properly seal.

Looks old. I love Grandma’s old canning jars because of the wavy glass, the little glass bubbles, and the beautiful colors. Unfortunately, older canning jars are also highly susceptible to cracking and should be retired. My friends at the extension office tell me that the lifespan of a canning jar is about ten uses which is why it’s a good idea to “cycle out” old jars at the beginning of the canning season. While you won’t get sick canning in old jars, you could end up with a mess on your counter if the glass cracks during the cooling down process.

More by this contributor:
How to clean and organize kitchen cabinet drawers.
How to deep clean and restore an old kitchen floor.
How to clean a dirty and badly stained kitchen sink.

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