Popcorn Definition

2. Sweet corn

Sweet corn is a gluten free cereal and it becomes ready to eat when kernels are in the milk stage, from 18 to 20 days after pollination (DAP). High quality sweet corn contains 70-75% moisture and 25% of the dry matter as simple sugars. At maturity sweet corn kernels are usually wrinkled and translucent, in contrast to the smooth or dented, flinty and or dented, flinty and or starchy characters of field corn kernels (Whistler, 1957; Galinat, 1971; Wann et al., 1971).

The principle difference between normal and sugary-1 maize is that latter accumulate highly branched, water soluble form of polysaccharide known as phytoglycogen (Morris and Morris, 1939). In comparison to normal kernels, sugary-1 kernels have lesser dry weight,

There is a hard outer covering called as pericarp or hull under which is a dense opaque starch layer and inner starch, which consist of the transluscent grains that are irregular polygons about 10µm across (Hoseney et al, 1983). On the other hand the unique characteristics of popcorn are caused by the fact that it has a much higher proportion of the translucent starch in its interior than other grains or other types of corn. This gives it the ability to pop and expand to 20 to 40 times its original volume. Popcorn is typically 12 to 14.5% water, with most of the water being located in the translucent starch granule. Popcorn expansion volume has been shown to be a quantitative trait with high heritability and influenced by three to five major genes (Lu et al, 2003; Ziegler, 2001). Each kernel of popcorn contains a certain amount of moisture and oil. Unlike most other grains, the outer hull of the popcorn kernel is both strong and impervious to moisture and the starch inside consists almost completely of a hard, dense type. As the oil and the water around the kernel are heated, they turn the moisture in the kernel, which has a moisture-proof hull, into a superheated pressurized steam. Under these conditions, the starch inside the kernel gelatinizes, softens, and becomes pliable. The pressure continues to increase until the breaking point of the hull is reached: a

Transgenic approach can also be used for further improvement of nutritional quality and for development of the next generation specialty corns with premise components of biochemical attributes so as to enhance their utility for specific purposes and usages.

There are tremendous variations in maize kernel composition for various physical and biochemical parameters in general and with major emphasis on starch, in particular. The variations in quantity and quality of starch in specific genotypes further make them specifically amenable to direct human consumption as well as industrial usage. This uniqueness and unparallel options further highlight the need for comprehensive understanding of the starch metabolic pathway. Apart from better knowledge and scientific basis, comprehensive information facilitates further modification and finer utilization of improved corns for food, feed and nutritional security. On account of parallels between other cereals, many findings can be useful and extrapolatable to other millets in general, especially with closer evolutionary and domestication