First of all, the outermost translucent peel (commonly known as seed coat) of popcorn is hard, with a thickness of 0.03~0.08mm, and consists of orderly and compact cellulose. It plays the role of sealing water vapor and increasing pressure. According to the determination, the mechanical strength of broken peel under high pressure is four times that of ordinary corn; Moreover, the thermal conductivity is fast, and the thermal conductivity is 1.9 times that of ordinary corn. When heated, the temperature in the grain will rise rapidly, but it will not burn.

Secondly, the endosperm of popcorn is large, accounting for about 4/5 of the whole grain weight, of which about 90% is starch. 75% of starch is keratin starch, which is distributed around the granules. When it meets high temperature, it becomes a hard and elastic colloidal substance, which can resist strong water and gas pressure. The other 25% is powdery starch, which is embedded in the center of grain by keratin starch. Starch granules and water are closely embedded in the protein skeleton interwoven network, and the gap is very small. These two kinds of starch are also found in the endosperm of common corn, but the proportion of keratin starch is not as high as that of popcorn, and its structure density is also poor, and its distribution position is not as good as that of popcorn.

Finally, the moisture content of popcorn should be appropriate. Generally, the water content of 13.0% ~ 15.0% can generate high enough pressure in blasting particles.