All digestion begins in the mouth. When a person chews their food, saliva is created. The saliva begins the break down process of the food for digestion. Starches which are a part of the carbohydrate class are the only type of food that begins chemical digestion in the mouth. The chemical digestion is also started with saliva.
All food digestion actually begins in the mouth. Chewing breaks apart the food, and creates saliva. Saliva aides in the digestion of food. Carbohydrates are the only type of food that goes through a chemical digestion in the mouth.