Food also benefits from alcohol's second remarkable quality: It bonds with both fat and water molecules. In this way, alcohol bridges the gap between our aroma receptors (which respond only to molecules that can be dissolved in fat) and food (which consists primarily of water). This is crucial, because most of the great "flavor" in food comes from aromas in the nose rather than tastes in the mouth. (Notice that you can't fully "taste" your food when you have a stuffy nose.)
Alcohol's ability to bond with both fat and water is well illustrated by a marinade or brine. In this case, the flavor compounds in aromatics like garlic, herbs, or other seasonings dissolve only in fat (i.e., they are fat-soluble). Alcohol helps carry those compounds into the meat that's soaking in the marinade. At the same time, alcohol also carries any water-soluble flavor compounds into the meat's cells. (Water-soluble flavors include sweet, sour, salty, and bitter.) The result of alcohol's efforts? More flavor and aroma in the marinated food. And it doesn't take much: Adding even a tablespoon of neutral-tasting vodka to a marinade or brine noticeably improves the flavor penetration of the marinade.
The same principle is at work when you baste a piece of meat with wine, beer, or spirits during cooking. Of course, the liquid helps moisten the meat's surface, but the alcohol also carries flavor compounds into the meat, improving its taste.