Canning onions

Asked September 11, 2019, 2:08 AM EDT

I have a recipe for canning balsamic caramelized onions. The recipe calls for 2 lb of onions and 3/4 of a cup of balsamic vinegar and 3/4 of a cup of sugar. That's it. The onions would be caramelized in a slow cooker without using any fat. I have seen the exact same recipe water bath canned and pressure canned. So I am confused. I know that onions need to be pressure canned but I'm wondering if the balsamic vinegar is enough of an acid to water bath can them. Thank you.

Hamilton County Ohio

1 Response

Thank you for the question. Because onions are a low acid vegetable they must be pressure canned to prevent botulism. Here is a link about pressure canning onions:
This is regardless of the addition of vinegar.

In addition, it is recommended to follow only safety tested recipes. The above link includes a recipe for pressure canning onions.

Another great reference online is the National Center for Home Food Preservation
Here is a link: