With prices topping $5 per gallon, more dairies are selling raw milk ¡ª and finding themselves at odds with public health officials. The federal government and a majority of states prohibit sales of raw milk to the public, claiming it is responsible for hundreds of people sickened in the past decade with salmonella, E. coli, Listeria monocytogenes and other bacteria.

"Raw milk continues to cause outbreaks year after year," said John Sheehan, who oversees plant and dairy food products for the U.S. Food and Drug Administration. "It is a concern for the FDA."