What's in Beer
http://home.howstuffworks.com/beer2.htm
Although there are barley grits, real grits are made of hominy corn. Here is an interesting quote about the history of grits from Quaker Grits
Turner Catledge, former editor of the New York Times, called grits "the first truly American food." Grits date as far back as 1607, when the colonists came ashore at Jamestown, Virginia. They were met by friendly Native Americans offering steaming hot bowls of "rockahominie," which was softened maize seasoned with salt and animal fat. It was here that our passion for grits was born.