Is it safe to assume wine is made from grapes? Not really. Is it safe to assume wine is made from fruit? Apparently not, as indicated by River Myst’s onion wine. It is fermented from 55% onions, 27% potatoes, and 18% raisins.
Jailhouse is another example of a wine with very little “fruit” and a little bit of raisin. It is 90% honey, 9% orange, 1% raisin, and spices.