PSA: I canned 40 jars of butter and half of them turned rancid in 6 months
Last spring I read that canned butter lasts forever so I did 40 pints in my garage in Boise and stacked them on a shelf. Checked them 6 months later and 19 jars had that waxy crayon smell, so I tossed them. Turns out butter is a low acid food and a water bath will not cut it, you need a pressure canner at 11 PSI or it just goes bad. What low acid foods have you guys had fail on you like that?