OK. How about organic butter then? Organic butter has no artificial colors or flavorings. There ya go!
Diacetyl is a naturally occurring ingredient, "a metabolic product of aroma producing lactic acid streptococci." One reason it has been isolated and used as an additive is that it provides at least part of the "butter taste" in real butter.
The question is, how much diacetyl is in different products, including real butter? I linked the results of a Seattle P-I test for diacetyl in various margarines and oils in post #10 above, but I would like to see a more modern, more extensive list that included real butter.