This is the main danger of homemade mayonnaise as well - it’s not the raw egg that gets you.

If you don’t add sufficient acid to the mayo, then your potato salad ends up in a perfect oxygen-free environment for botulism…

In general, canning oils at home is unsafe (unless you have a pressure canner and take it up to 121C). Canning water-based stuff with high acidity (pH < 4.3 or whatever) is pretty safe, as long as you follow a safe procedure and the seals are intact.

how do you know that garlic+oil could produce botulism?

I think I haven’t understood what kind of food + low oxygen/low acid + room temperature might create botulism… could you help me understand?

I derived that most of those things are animal related, but garlic+oil is not.

Thanks!!