Old (fermented) wine that was used for a libation that spills onto grapes will be prohibited or not, depending on it affecting the taste of the grapes. New wine, however, is the subject of dispute - are they only forbidden if the new wine affected their flavor, or any amount would be an issue (it's a machloket between Abaye and Rava, on taste vs. name). Also, the smell of the wine helps evaluate how good it is - via the "bat tiha" - a hole in the wine cask, and the tester would smell the wine at that point (via a tube, etc.). Cumin becomes a parallel example for smell and food, but then it stops short of being a real parallel, because of all the differences between cumin and wine.