Timjoebillybob
Grandmaster
- Feb 27, 2009
- 9,421
- 149
My Wife does most of our canning, and she has a fantastic book called Putting Food By. Putting Food By: Fifth Edition: Ruth Hertzberg, Janet Greene, Beatrice Vaughan: 9780452296220: Amazon.com: Books It goes through all the safety of canning in great detail. My understanding is that highly acidic foods (low Ph) are a lot less friendly to bacteria than higher Ph foods. Tomatoes are one of the most acidic foods commonly canned, we successfully hot water bath them with no vinegar, which is what both of our parents have done for years. I see in the USDA reference above, it suggests adding either lemon juice, vinegar, or citric acid, so I guess this is just my, but not supported by the government. I also noted they claim that Pressure canning makes the tomatoes more nutritious than hot water bath canning. I'm curious why that is. Any thoughts?
It used to be that they thought all tomatoes had enough acid, further testing found some varieties didn't and some were borderline. Also acidity can vary depending on growing conditions. So they recommend a little additional acid to be on the safe side. No idea about the nutrition except maybe that while they can at a higher temperature, it is for less time. Although in my experience not that much less when you consider cool down time for the pressure canner before you can open it.
