Last week I had a canning jar break in my pressure canner while I was canning bone-in chicken.
Sometimes you can hear a jar break in the canner during processing and sometimes you can’t.
Often when you’re not expecting it, a bad surprise and a big mess is in store for you when the top of the canner comes off.
I think the reason my jar broke was because the jar was not hot enough when I packed the chicken and then placed it into the canner.
There are several different reasons for jar breakage that you might want to keep in mind for your canning.
- Using “one trip” jars. A one trip jar would be an older type glass peanut butter, mayonnaise or other type of jar that commercial food came in.
At present it’s hard to buy food in glass jars so it’s not too much of a problem. But sometimes when buying a box or a lot of old canning jars at a yard sale or auction, you will come across them. Be sure to check second-hand jars and make sure that they are indeed canning jars. Sometimes a true Ball canning jar will appear to be a one trip jar but it really isn’t. To check to make sure, turn the jar upside down and look for a “B” on the bottom.
- Canning jars can break if you use a metal utensil to remove air bubbles. A metal utensil can cause invisible interior scratches on the jar. These scratches or small fissures weaken the jar and make it susceptible to breakage during pressure canning. Using steel wool or a brush with a wire stem to clean jars or using a metal utensil to remove the food product or to scrape the inside of a jar can also cause interior scratches.
- Jars can break during processing by putting hot food into a room temperature jar.
- Jars can break by putting a room temperature jar into boiling water or placing a jar that is not into the canner.
- Jars can break when removed from the canner if they are placed directly on a cool counter top or wet surface.
- Sometimes jars will break during water bath canning if they are not secure in a rack. With water bath canning, unless the jars are well seated in a rack the jars can knock against each other and break if the water boils too rapidly.
I was canning in the evening when my jar broke.
So I waited until the morning for the hot food on the bottom of the canner to cool.
And used great care and newspaper to clean up the mess.