[Vendome]

I could see that but, if she was just canning I’d think nothing of using the tomatoe as is.

[JRandomFreeper]

It depends. I tend to taste even stuff I'm going to can to make sure the flavor is right. If my tomatoes weren't acid enough, I'd add citric acid. If they weren't sweet enough, I'd add sugar.

In this case, from a food safety perspective, risk is moderately low, results could potentially be catastrophic, and the fix is easy. If I was going to be feeding it to my grandkids, I'd check the pH, if it's just for me, pressure can and forget it.

/johnny