2. Corn is divided into seed coat, endosperm and embryo, among which endosperm is the key to affect the sweetness of corn. Because corn will produce glucose through photosynthesis when it is mature, and transport it to the endosperm and store it in the form of starch. Although starch is a polymer of sugar chemically, it is not sweet to eat, which is why the common corn we eat is not sweet and tastes powdery.
3. Sweet corn is different. Besides starch, its endosperm also contains relatively high content of water-soluble polysaccharides. Among a series of genes controlling starch synthesis in sweet corn, one or several genes have a natural mutation, which is in a homozygous recessive state, cutting off the process of converting some reducing sugar into starch. This "small defect" has made sweet corn delicious.