Q: I have been told that its fine to use sterilized jars and put HOT soup in them — then turn them upside down and let them seal themselves.
Is this a good method for low risk foods?
— Question asked by Tara
Marisa: Tara, whoever told you that that was an appropriate way to can hot soup greatly misled you. Soup is a low-acid food, which means that it's a fabulous environment for botulism to grow. While you will achieve a seal with the upside down method, it won't be a strong one and there's a enormous chance of contamination and spoilage. So please, do not attempt to put up soups in this manner (and if you've already done so, in the interest of safety, I would recommend throwing them out immediately).
The ONLY way to preserve soups and stocks is to pressure can them or freeze them.
Marisa McClellan, our guest expert this week, is answering your questions on canning and preserving. Marisa writes Food In Jars, a blog devoted to canning, preserving, and other food in jars. She also teaches canning workshops.
Marisa couldn't get to all of your questions this week, but she's going to answer a few more of your questions over at her blog this weekend. So make sure to check in there and see if your canning question was answered!
Previous questions about canning answered by Marisa:
• Is It Safe to Can Meat Sauces?
• My Strawberry Jam Went Bad! Why Did That Happen?
• Is It OK If There Are Air Bubbles In Finished Jars?
• Is It Safe To Use My Own Recipes for Canning?
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Tara,
We stay away from canning soups. Instead, we bag them in ziplocs (quart size for individual portions) and lay them flat in the freezer until they harden... they they can lay however they want in the freezer. Getting them out to eat is a breeze. Just break them into chunks, heat, and serve.
I wish all the people who promote the upside-down method would just STOP telling new canners to do this. Please please please process the jars and stop taking chances.
The only caution I'd give for freezing soups is make sure it's not on a wire rack. Had a bag of tortilla soup do that once, I had to defrost the entire freezer to get it free when we moved! (Luckily I do that anyway, but I know that's not always an option for all households. This just happened to be in an apartment complex I was more than glad to get out of when our lease expired.)
Yep, I'd second freezing soups.
third for freezing soups - even if you dont want to do ziploc bags, Ball has new plastic BPA free freezer jars!
That's a quick way to die of food poisoning, using the turn-the-bottle-upside-down method.
I can soups all the time, though. I simply use a pressure canner to do so.
Freeze it in ice cube trays. This allows for easier portioning. Works best on creamier soups without a lout of big, chunky ingredients for obvious reasons.
Good luck!
I have been told that you can not pressure can on a glass top stove. Is this true?