We’ve probably all learned the hard way that storing food in jars in the freezer can easily become an annoying disaster, waste of food, and resulting clean up. When stock, sauce, soup, chili, or whatever is in the jar freezes, it expands, and this, the jar breaks.
For so many years I avoided putting any of my canned (mason jars, that is) in the freezer to store excess sauces, soup, or other things that do well in jars.
But alas! There’s a little known trick about doing it with no disasters.
Step One: Use only flat-walled jars (any size), not the kind that narrow at the top.
Step Two: Locate the “Fill Line” that can often blend in to the other textures on the exterior of your jars. That’s it!
Why it works: liquids expand as they freeze, so if your canned items have no way to go but horizontal, the glass will break from pressure. If there’s room to go up, all is well. I have multiple systems for storing food in my freezer, but I love how organized my stock, sauces, and soup are (labeled on top with a sharpie — contents and date).