Pressure Canner Explosion

[recruiterg]

Can anyone tell me why this bottle exploded in my pressure canner? I have never had any problems in the past. The only thing I can think of is that I waited a while after I boiled the salsa before I canned it and maybe the temp difference caused it to break the bottle.

[Worth1]

Bad jar or to fast of a temperature change as in air hitting it.
The temp of the salsa when you put it in there had no effect.
or head space.
not using rack and ring to tight.
old jars.

Sometimes it just happens.

Worth

[Darren Abbey]

Glass is funny that way. What looks like perfectly normal glass can have imperfections in it that will break at random times.

I used to work in a medical blood testing lab. We handled enough specimens that we routinely saw glass tubes shatter while nobody was touching them, simply from the change in temperature from shipping to room temperature where we were working. We really didn't like it when clinics would send us samples in glass tubes.

I also once saw a mercury thermometer snap in half upon warming, with nobody touching it and right when I was looking at it to check the temperature.

[Father'sDaughter]

Glad it was just a jar. The thread topic made me think your canner exploded!

[Worth1]

Originally Posted by Father'sDaughter

Glad it was just a jar. The thread topic made me think your canner exploded!

I think it was meant to attract attention like those yellow journalism headlines.

Giant frog swallows 86 year-old grandmother.

Worth

[ContainerTed]

My immediate thought was that you may have tightened the ring too much. The ring should be only "finger snug". You're trying to hold the lid in place so it will have good contact when the pressure and temperature come down. It the lid is too tight, pressure can't equalize between the jar and the inside of the canner.

Also, if you don't let the pressure come off the canner slowly, then the hot glass may not be strong enough to hold the pressure. Usually, the contents will bubble vigorously and you will lose liquid from the jar if you reduce the pressure too quickly. Any slight difference in the thickness of the glass in the jar, or a slight nick can become the weak point that fails.

I would ask if you have experienced any loss of liquid inside your jars when you do your canning, or do you "assist" the reduction of the pressure in the canner.

[coronabarb]

Is it a Ball/Kerr jar? Sometimes, people use old Mayo type jars which can often hold up okay in water bath canning but not pressure canning. Also, like mentioned if it is an old jar, that can happen. Thankfully, today's pressure canners have pressure regulators that help prevent explosions of old.

[DiggingDogFarm]

This problem isn't uncommon.
It doesn't take much of a scratch in the glass to cause failure.
I bought a new case of Ball quart jars about 6 months ago which contained a bad jar....oddly, there were serious scratches on the INSIDE of the jar but Ball did make it right.

[coronabarb]

That's true ^ ^ - I have been reading about NEW jar failures lately. I opened up a case of jars and one of the lids (not the ring) was dented half way around the thing.

[Father'sDaughter]

Originally Posted by Worth1

I think it was meant to attract attention like those yellow journalism headlines.



Giant frog swallows 86 year-old grandmother.



Worth

Unfortunately, since the 2013 Boston Marathon, the words "pressure cooker" used together with "explosion" are BIG attention getters around these parts...

[Tomato Beth]

I am in a couple of canning groups, and there are many complaints about the Walmart jars breaking and the lids warping and not sealing correctly. I have had a jar break when I took it out of the canner and set it on the towel. The rest of them were fine, so I think it just might have been that jar's time to go to jar heaven.

[AlittleSalt]

Originally Posted by Tomato Beth

I am in a couple of canning groups, and there are many complaints about the Walmart jars breaking and the lids warping and not sealing correctly. I have had a jar break when I took it out of the canner and set it on the towel. The rest of them were fine, so I think it just might have been that jar's time to go to jar heaven.

We had 2 Walmart jars break during a simple water bath. They are the Mainstays brand. We needed canning jars and the name brands were sold out - so we gave Mainstays a try. Never again.

[Tomato Beth]

Quick additional note--salsa can be water bath canned, unless you prefer the pressure canned recipes.

[coronabarb]

Was answering our state food safety and preservation hotline this morning when the subject of pressure canning salsa came up. I did not find a tested/approved recipe for that...only water bath recipes. (I did not check the Ball Complete Book yet) I would stick to approved recipes for salsa because of the botulism danger...or freeze it. It's one of those low acid things that you really can't make up a recipe and hope you are processing it long enough.

[clkeiper]

Originally Posted by coronabarb

Was answering our state food safety and preservation hotline this morning when the subject of pressure canning salsa came up. I did not find a tested/approved recipe for that...only water bath recipes. (I did not check the Ball Complete Book yet) I would stick to approved recipes for salsa because of the botulism danger...or freeze it. It's one of those low acid things that you really can't make up a recipe and hope you are processing it long enough.

I am confused by this comment. Why would a pressure canner be less safe than a water bath method? A pressure canner heats to a higher temperature than a water bath. Botulism should never be an issue with a pressure canner, should it? If it is low acid it should be pressure canned anyway, according to the ball book.