Food's a cool idea. Is there anywhere that sells cell phone credit? That's something I'd love to buy with bitcoins.
Food is a limited service, because you need to provide faster delivery to which you need to open stores in various locations, if not it won't be profiting as well won't be effective. Also we cannot preserve it long same as that we hold the digital goods.
Well you can choose and identify the type of foods that you are going to sell. What do you mean that we cant preserve it? There are frozen goods and are good for shipping if you will visit the supermarket, you can see there the imported products, I guess the supermarket is the one to adjust for accepting bitcoin.