I had prepared a full load of jarred tomatoes properly prepared and just started putting them in a boiling water bath. I'm not sure, but this may have been the cause of the breakage of 2 qts, right next to each other....as I put the last qt jar in, I lifted it slightly to make sure it was properly seated. I heard a loud "pop". I figured it had broken but I went ahead and closed the lid knowing that I'd probably have a mess to clean up. I did. Not only was that jar broken, (the bottom fell out when I lifted it out of the canner), but the one next to it did the same thing. That may have been caused by the first qt tipping over and resting against it during processing. Not sure. But anyways, it was not only a disappointment, but a loss of time, good tomatoes, and the jars. No one wants stuff like this to happen. Any ideas?

Thanks,

Barb

So if the jars were hot as they are supposed to be and filled with hot contents as are supposed to be then the water in the canner was far too hot. It isn't supposed to be boiling. Just hot, max. of 180 degrees.

It often happens when folks let the filled jars sit on the counter cooling as they fill the remain jars.

Sorry for the mess.

Dave

As Dave said, thermal shock is identified by a crack that runs around the lower portion of the jar and sometimes up the side (the bottom falls out).

A vertical crack that runs up the side and may "fork" is an internal pressure break. That's caused by inadequate headspace, sudden changes of temperature in a PC (forced cooling by running water over the top of the canner or removing the weight before pressure reaches zero).

Impact breaks look like a windshield does when a rock hits it. I think of this one everytime someone returns canning jars clanking around in a plastic bag. It also can happen if a jar is damaged by a metal knife used to remove air bubbles or just the wear-and-tear of age such as scratching or rubbing.

Carol

Also, how do you test to make SURE you have a good seal when taking them out? Shouldn't there be a sound of the lids sealing? A little "ping"?

~Barb

Big no-no. All the approved tomato canning instructions call for boiling liquids - even the raw pack instructions.

Jar may seal in the canner, immediately on removal or even 10-20 mins. later. So while the ping/thunk is nice to hear you don't always hear it. A true seal is determined by the concave shape and firmness of the lid center when you check them several hours later. Then once you remove the rings you can test the seal the next day by carefully lifting the jar by the lid.

Dave

You sound like a pro :)It's so nice to see people willing to help out others on this forum.

Thanks again,

Barb

They'll be a little softer but still perfectly fine for soups or other cooked recipes.

Basically with a jar that's sealed you don't have a "bouncy" lid. It's solidly concave without spring. But often you don't hear anything, either because the jar's already sealed, as Dave mentioned, or because there's product against the lid, dulling the sound.

Carol