Nanjing's legendary food wholesale shop...

Hi. I have heard from a few people that there is a large food wholesale joint open to the public somewhere in the city, but no one can tell me where. Apparently it even sells Western things like butter and cheese in crazy quantities at reasonable prices. All I've managed to ascertain is that it's NOT in the wholesale area where you can buy clothes, homewares etc. Does anyone know if the legends are true and, if so, where it is?