My phrasing was off, i didn’t mean to say that that actually used rancid or sour milk. Rather the flavor of butyric acid is commonplace in a lot of American chocolate. And it’s a flavor i quite despise (despite loving Hershey’s growing up), hence the preference for non-American chocolate. I understand that sweeping generalizations are almost never true, and that there are plenty of American chocolatiers who make chocolate without that distinct sour note, but that doesn’t denigrate the fact that you can go to most places in the states that sell chocolate and get something with a sour note. For many people they like that, I personally don’t.