Saliva

Saliva a secretion from three pairs of salivary glands in the mouth, has various components, including some sodium chloride (common salt) and sodium bicarbonate. The two which help most to prepare food for its passage to the stomach are a protein, mucin; and the enzyme ptyalin, a type of amylase. The former lubricates the food; the latter hydrolyses starch to maltose. A human adult normally generates 1–1.5 litres (1.75–3.5 pints) of saliva daily.

The birds’ nests that are made into soup consist of dried saliva of birds.