What you said got me wondering about whether you could fix that by adding some vinegar, which led me to this interesting article: https://www.clemson.edu/exten

What you said got me wondering about whether you could fix that by adding some vinegar, which led me to this interesting article: https://www.clemson.edu/extension/food/canning/canning-tips/40old-pickle-recipes.html https://www.clemson.edu/extension/food/canning/canning-tips/... Tl;dr your canned food can get a fungus that eats the vinegar, reducing the acidity, and allowing botulinum to grow.