Carbohydrates are called "the fuel of life." They occur in larger amounts in plants, as well as in all products that contain vegetable components, such as bread or pasta.
The problem is, however, that the cat's gastrointestinal system cannot make use of raw carbohydrates from plants completely. Vegetables and grains such as rice or rolled oats have to be cooked so cats can digest them, and to serve as a highly nutritious source of energy and vitamins, minerals and trace elements. Carbohydrates in commercially prepared food have already been cooked and are very digestible.