By Elizabeth Gawthrop Riely
This summer when you bite into an ear of corn freshly picked and full of juicy sweetness, you will be savoring a food plant so extremely old that it does not grow in the wild. Scientists believe that corn, or maize, botanically Zea mays, originated in Mesoamerica. Exactly where is uncertain, but Mexico’s Tehuacán Valley seems likely. Archeologists have even found cobs as small as your thumbnail dating back approximately 5,000 years, and even this early corn was cultivated. Corn cannot sow itself; it needs humans to plant it. The mystery of wild corn, which predates human habitation in the region, remains unsolved.
Corn has the remarkable trait of being very pliable genetically, of hybridizing easily. Today, in fact, there are more varieties of corn than any other food crop. Once early humans realized its value as food, they began to nurture it and selectively breed it to suit their needs. They observed that it sprouted better in midden heaps, after digestion had begun the process of germination in the gut, and that birds dispersed the kernels that they liked. They noticed too that it had a short growing season. Over millennia corn spread all over Central, North, and South America, helped by the ease of carrying the seed kernels from one place to another. It was often grown with squash, beans, and peppers, or potatoes, and oca. Where corn went, civilizations flourished.
Native Americans bred corn larger and larger, with more rows with bigger kernels on the cob. Colors varied widely: white, yellow, red, brown, blue, black, these colors often mottled or streaked. The types of corn developed into those we know today: flint corn, usually dried, with hard skins and a flavor the Indians preferred; dent corn, with hard sides and an indentation on the top, mostly used for animal fodder; flour corn, with starchy large kernels, used for cornmeal especially in South America; popcorn which the Indians liked just as we do; and sweet or green corn, with its tender skin and sweet kernels which have not yet converted their sugar to starch. We know this last type as corn on the cob, and it is the main subject of this article.
Corn is a grass and grows as tall as a very tall man. It cannot sow itself, requiring humans to pick the seed-head ears and choose which seeds to then replant. As the stalk grows up and reaches maturity, wind pollinates the plant. The tassel on top is the male part, the corn silk the female part covering the cob, one thread to each kernel. The special leaves of the husk, which cover and protect the seeds, do not fall off when dried, thus preventing corn from self-propagating.
In the Mesoamerican exhibition rooms at the Boston Museum of Fine Arts and other museums, ancient stone carvings, metalwork, and hieroglyphic drawings show very detailed figures. To my untutored eye these are strangely human and fascinating glyphs, yet totally unfamiliar and barely recognizable—until I notice ears of corn. The rows of kernels on corncobs are unmistakable, and then I begin to make out shoots and curls and leaves of corn.
This staple food was essential to the Mesoamericans. It sustained whole populations of various empires and tribes—Olmec, Maya, Inca, Aztecs, and others—each with their different words for corn. It is not surprising that corn became central to their mythology and imagination. In their understanding of the cycle of life, the seed of corn was fertilized with blood—human blood of enemies killed in battle or in sacrificial rites of their own people, sometimes highly ritualized bloodletting of rulers without death. This mythology and its depiction in drawings and objects, often combined with human figures, is discussed in fascinating detail by Betty Fussell in her book, The Story of Corn, so that the pictures begin to make a glimmer of sense to me.
Columbus saw corn, mahiz, on his first voyage in 1492, and the description of it when he returned to Spain showed how Europeans had nothing to compare it to. Settlers in the New World didn’t grasp its goodness for a long time, considering it inferior to wheat, barley, and oats. But the Native Americans ate corn with squash and beans, where it was nutritionally complete despite its lower protein content, as well as easier to grow and harvest. The “Indian (Native American) meal” contained no gluten, but eventually the settlers learned to appreciate it and use it well. Indeed, corn is a better converter of energy than any grain.
“Corn is a generous crop to man,” says Patrick Porter, botanist and owner of Porter Family Farm in Natick. “It’s drought-tolerant and nutrition-rich.” In telling how its cultivation helped drive early humans in the Americas, he describes how the seeds “with their apical roots can break through and germinate in non-friable soil, ‘even in the middle of woods. It’s what we call a soil-buster.’” Again using farmers’ terminology, corn is a heavy feeder, he says. Then he rattles off his favorites of the 50 or so varietals he has grown, the days to maturity, length of the ear, number of rows, plumpness of the kernels, all increasing as summer goes on.
Late season is “ample,” he says, “with 10-inch ears and 32 rows. Now, that’s real corn.”
Words for corn, to try to clear up some of the confusion:
Zea mays - Botanical name in Linnaean binomenclature
Corn - What North Americans call maize, in any of its many varieties. In Britain, corn is the generic word for the dominant grain crop of a region (Cornmarket Street in England is where the wheat market was), such as wheat, oats or barley. Corn in older English means a small particle or grain, as of salt (hence corned beef which is beef preserved with grains of salt).
Maize - British for what North Americans call corn (sweet corn, summer corn-on-the-cob corn); from the Taino (Arawak) word mahiz, as Columbus was told when he first encountered it in 1492. Often, especially in Europe, maize denotes animal fodder.
Cornmeal - Dried kernels of corn, either white, yellow, occasionally blue, ground to varying textures, coarse or fine, for different purposes. Stone-ground or water-ground cornmeal is the traditional process, keeping the nutritious germ but prone to spoilage unless refrigerated or used quickly; industrial steel-ground cornmeal processing removes the germ and hull, but has an indefinite shelf life. Early English settlers called this Indian meal, as it appears in cookbooks and dishes (such as Indian pudding). Polenta is an Italian type of cornmeal.
Cornstarch - Very fine white flour milled from the corn endosperm and used as a thickening agent. The British term for this is cornflour (yes, very confusing).
The Basics About Corn
Always buy corn picked as recently as possible, before the sugar has had time to turn to starch. From your yard is best, with the pot already boiling. If you drop an ear on the way in, says Patrick Porter, don’t stop to pick it up.
The farmers market or a farmstand is your next best source. For me, out-of-season corn is so disappointing that I am happy to wait for its seasonal return each summer. Frozen will do in a pinch, cooked or baked into a dish, but don’t even consider canned corn. That’s for Arctic explorers.
When I buy corn at the farmers market, I always cook the whole batch that night to capture its sweetness. For the next day I can reheat or steam it in a pot of water, or put it on the grill for burnishing, perhaps brushed with seasoned butter or oil, or cut off the kernels for another purpose.
To boil corn on the cob, shuck the leaves and remove the silk; trim the stalk ends to be sure the cobs fit in the pot. Drop the ears in a pot of boiling water (or steam over a small amount, if you prefer.) For length of time, I have read everything from less than one minute to ten minutes or more. I don’t see that this is something to worry about, as raw corn is delectable and nutritious. And by the way, I cook it until the ears rise to the surface and a little more, perhaps 3 minutes; in the lapse of real time, probably longer. Take the ears out with tongs, but keep the hot water in case you want to reheat your second or third ear. Serve with good butter, salt, and bibs, at least two ears per person. This is American food at its best.
To grill corn on the cob, there are many methods. My preferred way is to pull back the husk but not detach the leaves, remove the silk and wrap the husk back up tightly. Drop them in a big pot of cool water to soak for a few hours or whatever is convenient. At barbecue time, put them directly on a cooler part of the grill, turning once, where they will cook in about 15 minutes. Let your guests unwrap their husks. This is part of the fun.
In most of the recipes below, the corn is cut off the cob and “scraped” to remove the milk. That creamy interior is part of the lusciousness of these dishes. I have found the best method, is to stand the ear up in a large bowl (to catch the splatters) and with a sharp knife cut downwards to sheer off the tops of the kernels. Then go over the rows again with the back of the knife to scrape off the inside, but don’t go too deep as you don’t want the hard cob.
Incidentally, corn on the cob is excellent for distracting and soothing children who are teething.
Leftover corn cobs make a good stock. Put them in a pot of water to cover generously, with perhaps a large sliced onion, stalk or two of celery, and sprigs of parsley, and simmer for an hour or two. Cool and strain this stock which will give surprising depth to corn chowder and vegetable soups like the one here, but with fewer calories than milk or cream.
Get the Recipes
Elizabeth Gawthrop Riely’s articles have appeared in many newspapers and magazines. Her cookbook, A Feast of Fruits (Macmillan), was published in 1993 and her dictionary, The Chef’s Companion, 3rd edition (John Wiley & Sons), in 2003. She was editor of The Culinary Times, published by the Schlesinger Library, from 2000 to 2009. Beth can be reached at firstname.lastname@example.org.