How can I tell if it is safe to can a particular homemade sauce? Is it just a function of pH and technique (pressure vs boiling water) or are there any other factors in play?
Specifically, I would like to can a tomato sauce that I use as a base for pasta dishes. I do not have an exact recipe but it's basically:
- cook down loads of tomatoes until there's very little liquid left
- whisk olive oil in to tomatoes
- saute some garlic, anchovies, and red pepper flake
- stir in to tomatoes
The tomatoes are obviously acidic, and I assume this intensifies as they cook down. Does adding the olive oil, garlic, or fish create issues though?