How do we know that the olive oil we buy from the grocery store is actually authentic? I thought most of the olive oil in the US contains cheaper seed oils, just like most of the honey contains corn syrup.
If it says "Extra Virgin" it's supposed to be olive oil, cold extraction, probably first press (leaving alone frauds). If it doesn't (just says "olive oil"), it's probably olive oil mixed with all sorts of other vegetable oils.
In the US, yes. And if it's a mixture of olive and something else they also just can't call it "olive oil" on the front label either.
On the other hand that's just what's required. If nobody's looking closely, who's to say what you're actually doing, or what has happened from your upstream suppliers with or without your knowledge?
> Do they not have to declare the other ingredients on the packaging?
They do but it's the same with everything else: there are definitions of what is something and sometimes they allow unexpected ingredients or mixtures that we wouldn't have expected.
I think milk or milk-based is one of those things. Same for beef burger (if it's 62% beef than it's allowed to be caled a beef burger, no matter if it tastes like cardboard).
Adulteration of OO is definitely an issue. There's not a lot of testing. I tend to think that if you buy CA grown/produced olive oil it's more likely to be authentic.