Sweet Corn

Corn (Zea), known to much of the world as maize, belongs to the Poaceae family, along with bamboo, wild rice (Zizania), wheat (Triticum), rice (Oryza),  oats (Avena), barley (Hordeum), millet (Echinochloa) and rye (Secale).

Corn is a cereal grain domesticated by indigenous peoples in Central America as much as 80,000 years ago. The ancestor of corn may be a Mexican grass called teosinte, and early corn may have looked more like oats, with each individual kernel covered in a husk. The Olmec and Mayans cultivated corn throughout central and southern Mexico. The corn we know today was developed over the centuries. The leafy stalk produces ears that contain fruits called kernels.

Between 1700 and 1250 BC, corn spread through much of the Americas. Native American people thought of corn as a gift of the gods and included it in their religious ceremonies. They called corn, squash, and beans the “three sisters,” and they planted them together to form the staples of their diet. Native Americans processed corn by soaking and cooking in an alkaline solution, usually using solutions of lime (calcium hydroxide, not the citrus fruit) and ash (potassium hydroxide). This process made the corn easier to grind, improved its nutritional value, flavor and aroma, and reduced toxins.

Corn was introduced to Europe by Christopher Columbus, and it was grown in Spain as early as 1498. Due to its high yields and adaptability, it quickly spread through Europe, and later to Africa and India. Portuguese colonists grew corn in the Congo as early as 1560, and it remains a major food crop in parts of Africa.

Unfortunately, the process of soaking the corn in lime water did not accompany the grain to Europe and beyond, perhaps because the Europeans already had more efficient milling processes for hulling and grinding grain mechanically. Corn’s molecular structure makes at least half of its niacin unavailable to humans. Without alkaline processing, corn is much less nutritious, and pellagra, or niacin deficiency disease, struck many populations who depended on corn as a staple. Pellagra victims suffer from skin eruptions, digestive and nervous disturbances, and mental deterioration. Like many deficiency diseases, it is entirely avoidable by eating a varied, balanced diet.

The sweet corn we know today was discovered in 1779 in an Iroquois village along the Susquehanna River in central New York, but European Americans didn’t really start eating corn in large quantities until the 1840s. Today corn is the second most plentiful cereal grain in the world behind rice.

Corn is low in fat and calories and is a good source of fiber, with three grams per ear, and a high ratio of insoluble to soluble fiber. Corn is a good source of fiber, with a high ratio of insoluble-to-soluble fiber. Yellow corn is high in Vitamin A; white corn has much less. Both offer moderate amounts of folate and vitamin C, with magnesium and potassium in abundant quantity. All varieties of corn have their own antioxidant profiles. Yellow corn contains the antioxidant carotenoids, with especially high concentrations of lutein and zeaxanthin. Blue corn has anthocyanins. Purple corn contains a hydroxybenzoic acid, protocatechuic acid. Corn provides three grams of protein per ear. Compared with beans, corn is lower in lysine and tryptophan, two essential amino acids, than beans, but higher in methionine. Eating corn along with beans and squash, as the Native Americans did, provides a perfect balance of essential amino acids.

Sweet corn can be enjoyed raw, roasted, or steamed. The Environmental Working Group lists corn as the second cleanest crop in terms of pesticide residue. Unfortunately, much of the corn crop is genetically modified, so it’s still best to buy organic and local whenever possible. Summer is the season for fresh corn.