Mccormack,
Patents are only granted on inventions which are new and non-obvious. It is my understanding that it is, in practice, difficult to get a patent on a recipe if what differentiates your recipe from all the others is a little more butter, or a few extra moments under the grill.
Neither can recipes be copyrighted.
"A mere listing of ingredients is not protected under copyright law. However, where a recipe or formula is accompanied by substantial literary expression in the form of an explanation or directions, or when there is a collection of recipes as in a cookbook, there may be a basis for copyright protection. Note that if you have secret ingredients to a recipe that you do not wish to be revealed, you should not submit your recipe for registration, because applications and deposit copies are public records. See FL 122, Recipes."
http://www.copyright.gov/help/faq/faq-protect.htmlRecipes (like the secret formula for Coca-Cola) are most always best protected as trade secrets. It is also worth noting that trade secrets last forever and cost nothing.
Perhaps this is why good cooks never give away their secrets.
Regards,
Eric Stasik