I should have been clear, I was thinking of Cool Ranch Doritos (this was covered in an NPR piece years ago and that was one of the examples). As for Mountain Dew... "citrus". It is the classic case of amplitude.
Take away the acid and it would be sickeningly sweet. Dial down the sugar and it would be absurdly tart or bitter. It's only together, in mass quantities that it achieves a kind of blitz effect.