Purple corn


Purple corn or purple maize is a variety of flint maize originating from South America. It is more commonly seen in Peru, Bolivia, Colombia and Ecuador.

Uses

The kernels of purple corn are soaked in hot water by people of the Andes to yield a deep purple color for foods and beverages, a practice now recognized for its industrial uses as a colorant. Common in Peru, purple corn is used in chicha morada, a drink made by boiling ground purple corn kernels with pineapple, cinnamon, clove, and sugar, and in mazamorra, a type of pudding. One of the most popular purple corn food uses is the "Api", a smoothie served hot and sometimes called "Inca's dessert".

Color chemistry: anthocyanins

The pigment giving purple corn its vivid color derives from an exceptional content of a class of polyphenols called anthocyanins. Cyanidin 3-O-glucoside, also called chrysanthemin, is the major anthocyanin in purple corn kernels, comprising about 73% of all anthocyanins present. Other anthocyanins identified are pelargonidin 3-O-β-D-glucoside, peonidin 3-O-β-D-glucoside, cyanidin 3-O-β-D-, pelargonidin 3-O-β-D- and peonidin 3-O-β-D-. Similar results for anthocyanin content were found from a variety of purple corn grown in China.
Evaluating growing conditions for anthocyanin and total polyphenol content, one research group found that field location was an important determinant, whereas seedling density and soil potassium content were not.
For ease of extractions, scientists have explored components of the purple corn plant for yield, such as kernels, cob and husk, possibly allowing use of a plentiful, non-edible residual biomass in cobs or husks. Husks of the purple corn plant contain about ten times higher content of anthocyanins than do kernels.