Though it’s technically a grain, we eat fresh corn as a vegetable. Like other grains, it can turn starchy soon after it’s picked. If you are buying corn fresh, cook it as soon as possible. You’ll find white corn to be a little sweeter with smaller kernels, but it is usually interchangeable with yellow corn. Canned or frozen corn is easy to use in recipes and good to keep on hand for adding to salads and soups.