Why is mastication essential for digestion?
Most of us think about mastication (chewing) when we think about eating. However, as demonstrated by infants, the elderly, and those who are on a liquid diet for other medical reasons, mastication is not essential for digestion.
Mechanical digestion is the same thing as chewing, or mastication. It does not need any digestive juices, because that is considered chemical digestion. Chemical digestion in the mouth during chewing is mainly by the aid of saliva which has, among other enzymes, salivary amylase which initiates carbohydrate digestion.
Salivary amylase aids in digestion of polysaccharides. Remember that digestion actually begins with chewing (mastication), which can be distinguished as mechanical and not chemical digestion. The salivary glands of the oral cavity secrete saliva (hence the name). 98% is water and 2% is electrolytes, mucus, glycoproteins, enzymes, and other compounds such as the antibody IgA (immunoglobin A). Mucus, lysozyme, and IgA aid in immune response.
Mastication, or chewing the food, is an essential part of the digestive process. Even foods that are small enough to swallow wihout chewing should be chewed. Mastication prepares food for swallowing, helps get the diggestive process started, makes it easiert to absorb nutrients and helps promote feelings of fullness after eating.