Today I wanted to add to the fun facts about canning history with this topic.
Why are mason jars made of glass?
You may not have ever thought about it but sometimes odd questions like that come to me and I wonder why are mason jars not made out of clay like pottery or crocks? I also find it amazing that since canning was invented we still use the same basic design of glass jar. The only thing that has really changed about them is the method of sealing.
As I mentioned in a previous post, Nicolas Appert was the inventor of heat processing food preservation that he developed by placing cooked food in glass jars, removing as much air as possible and sealing the jars with corks that were wired in place then processed in a water bath. He used glass because he believed that it was air that caused food spoilage and glass is not easily penetrated by air. I also briefly documented the story of the inventor of the mason jar here.
Even though it wasn't known at that time that it is actually microorganisms that cause spoilage, Mr. Appert wasn't entirely wrong because many of those microorganisms are airborne. Later in the 19th century more was learned about what causes canned food to spoil and that these bacteria are not only in the air but also in the food and that water bathing didn't process certain foods at high enough temperatures to kill the microorganisms in them. So pressure canning was developed. Fortunately glass jars are able to withstand the pressurizing process when done properly and if well taken care of, glass jars can be reused over and over again.
So when we are looking at what seems to be an ordinary mason jar what we are actually seeing is the result of one of the most enduring and ingenious inventions of all time. They also make a pretty cool container for your iced sweet tea or garden tea lights and I like to use the images of them to create unique canning themed products for home canners like you!
Like this one that you can purchase in my shop The Jelly Jar.
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| Buy it Here |
So 212 degrees isn't enough to kill those microorganisms? Maybe that (plus improper sealing) is why canned veggies occasionally go bad. I personally experienced dill pickles growing mold on the top. Most unpleasant.
ReplyDeleteI have never had mold grow on my pickles before, of course I do not ferment them ahead of time. I was researching and ways to prevent that happening is to make sure your veggies are fresh, use the correct amount of canning salt ( not table salt!) remove the blossom end of the cucumber. Make sure your headspace is correct and add an extra 5-10 min to the processing time. I hope that helps you nix the mold!
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