... is the first digestive juice. It is alkaline and contains a ferment called ptyalin. This acts energetically on the cooked and gelatinous starch, and slowly on the raw starch. Starch is quite insoluble in water, but the first product of salivary digestion is a less complex substance called soluble-starch. When time is allowed for the action to be completed, ... — The Chemistry of Food and Nutrition • A. W. Duncan