New York Times, November 2000

The alcohol in the vodka enhances the flavor of the tomatoes. Some flavors are alcohol-soluble, meaning that they will be released only by the addition of alcohol. Vodka can help bring out these flavors without contributing another flavor, as wine or brandy would.

So a tomato sauce made with a touch of vodka can be slightly more intense than one made without. This is a particular boon if you are using less than perfectly ripe, late-summer tomatoes, which may need that flavor boost.

Vodka is preferred by some because it does not add any any flavor to the dish. Others prefer something like wine to add another layer of flavor to the dish. In this dish, it also helps carry the flavor of the cream to the taste buds, sometimes the fat needs a carrier to get it to the tongue.