One of those questions I've always wondered about:

AAWE Working Paper No. 36 Economics
Can People Distinguish Pâté from Dog Food?
John Bohannon, Robin Goldstein and Alexis Herschkowitsch

Abstract

Considering the similarity of its ingredients, canned dog food could be a suitable and inexpensive substitute for pâté or processed blended meat products such as Spam or liverwurst. However, the social stigma associated with the human consumption of pet food makes an unbiased comparison challenging. To prevent bias, Newman's Own dog food was prepared with a food processor to have the texture and appearance of a liver mousse. In a double-blind test, subjects were presented with five unlabeled blended meat products, one of which was the prepared dog food. After ranking the samples on the basis of taste, subjects were challenged to identify which of the five was dog food. Although 72% of subjects ranked the dog food as the worst of the five samples in terms of taste (Newell and MacFarlane multiple comparison, P<0.05), subjects were not better than random at correctly identifying the dog food.

So, it appears people don't like eating dog food. Now there's a surprise!

Not entirely sure what that's got to do with wine economics though?