Milk is one of two beverages of Kentucky recognized by statute, and was designated as its official drink by the Kentucky legislature in 2005.

According to State Senate Bill 93, “milk production and the manufacture of dairy products are major contributors to the economic well-being of Kentucky agriculture.”

Currently there are 20 states which acknowledge milk as their official drink. While milk is the only official drink claimed by multiple states, all 30 remaining states' choices are unique, though various alcoholic beverages are designated in Virginia and Alabama, as well as the capital, Washington, D.C. and Puerto Rico, a territory.

A second Kentucky beverage is a regional soft drink, Ale-8-One, known colloquially as Ale-8. The legislature formally adopted it as "an original Kentucky soft drink" in 2013.

Kool-Aid is actually the state soft drink of Nebraska.

States often promote products, animals, birds, events, and even songs with an "official" designation as part of marketing efforts to foster tourism and broaden their economies, or to recognize aspects of their history.

More Info: en.wikipedia.org