Saliva is a mixture of water, mucus, antibacterial substance and digestive enzymes. Therefore, saliva has many uses. One of the digestive enzyme alpha-amylase helps to break down the starch present in our food in to simpler one like glucose and maltose. Whenever we chew, we activate these glands to secrete an enzyme to breakdown the food. Saliva has lubricating properties. It protect the inside cavity of our mouth, teeth and throats as we begin to swallow the food bolus. It also cleanses the mouth after the meal and dissolves it into chemicals that we perceive as taste.
Parotid glands are the largest salivary gland. Each gland is approximately 6 cm long and 3-4 cm wide and can weigh up to 30 grams. They are located within each of our cheeks. In our oral cavity they are responsible for the secretion of about 20% of saliva. This saliva is known as serous i.e. more liquid and fluid. It helps in the first phase of the digestion of food, facilitate mastication "chewing". These glands secrete protein-rich fluid which is a suspension of alpha-amylase enzyme.
