Midrash su Salmi 110:7

1) I might think that even a gourd which fell into the atmosphere of the oven and was not predisposed (to the acquisition of tumah) would become tamei; it is, therefore, written (Vayikra 11:34) "upon which water came." This tells me only of water (as a predisposing element). Whence do I derive the same for dew, wine, oil, blood, honey and milk? From "drink" — this is wine; "that is drunk" — this is blood, as it is written (Tehillim 110:7): "From a river, on the way, shall he drink (blood), wherefore he shall lift (his) head." Whence are other liquids derived (as predisposing elements)? From "and every drink." If "every drink," I would think (even) mulberry juice, fruit-juice, pomegranate juice, and (the juice of) all other kinds of fruits. It is, therefore, written "water." Just as "water" is characterized by the absence of a qualifying epithet, so I include dew, wine, oil, blood, honey, and milk, which have no qualifying epithets, and I exclude mulberry juice, pomegranate juice, and (the juice of) all other kinds of fruits, which have qualifying epithets.

4) "which shall be drunk": to exclude foul drink. These are the words of R. Eliezer. They said to him: No drink is out of bounds for birds or cows, (so that foul drink, too, predisposes to tumah).