Excerpt: The popcorns are a special group of flint corns used for "popping," as the name suggests, for eating out of hand or in confections. They are characterized by the small size of the kernels and their excessive hardness, and by the excessive proportion of the corneous endosperm or horny substance contained in the kernels, which in turn contains a large percentage of moisture and gives the kernels the property of popping or turning almost completely inside out on the application of heat. ...The actual popping of the kernels has been shown to be due to the expansion of moisture in the starch-cells, the application of heat converting the moisture into steam, making the cell-walls give way and causing an explosion with sufficient force to alter the entire form and texture of the kernel.
