Although the corn that grows around the world comes in a large and diverse palette of colors—there's blue, there's orange, there's purple—at most U.S. markets the selection is a bit more limited, with options ranging from yellow or white to...yellow and white. We got to wondering—call us bi-color-curious—is there any difference between the two?
So, what is the difference between yellow and white corn?
Frankly not much, at least in terms of flavor. Though some people believe that yellow corn is sweeter, that's not the case. The only difference is that the naturally occurring pigment that makes those kernels yellow, beta carotene, gives them a bit of a nutritional edge over white corn—beta carotene turns into vitamin A during digestion.
In fact, in 2008 researchers found a couple of long-lost strains of corn—yellow and, particularly, orange—that were so heavy in beta carotene that they were touted as a possibly crucial source of the nutrient in parts of Latin America and Africa, where chronic vitamin A deficiency can lead to blindness. (One challenge may be that corn-color preference tends to be culturally specific—in the U.S. the norm is yellow and/or white corn, whereas people in Africa are accustomed to white corn; orange corn is popular elsewhere, like in parts of Asia.)
Do other colors of corn contain other nutrients?
Let's take a step back and clarify what we mean by "corn." Long ago in Europe, "corn" was just a generic term for whatever happened to be the major crop in a given country or region—in England "corn" could have referred to wheat, whereas in Scotland or Ireland it could have meant oats. So when European colonists arrived in what would become North America and brought the primary New World crop back to Europe—a crop more properly referred to as maize—they called it "Indian corn."
"After a while domesticated maize became so ubiquitous that the word 'Indian' was dropped, and all maize became corn—like all facial tissue becoming Kleenex," writes Mark Lasbury of the fascinating biology blog As Many Exceptions as Rules.
Today the term "Indian corn" refers to ears of corn—usually flint corn, a cousin of sweet corn—that are vibrantly colored and typically ornamental. But the corn—er, maize—colonial-era Native Americans grew was also vibrantly colored, in an array of hues, described by the Connecticut colony governor John Winthrop Jr. as "red, yellow, blew, olive colour, and greenish," with some black kernels, and so on. A piece in the New York Times a few years ago reported that some of these colors—black, red, blue—indicated the rich presence of anthocyanins, pigments that "have the potential to fight cancer, calm inflammation, lower cholesterol and blood pressure, protect the aging brain, and reduce the risk of obesity, diabetes and cardiovascular disease."
How do I get those nutrients, then?
Look for corn with the deepest yellow kernels. Look for blue or purple cornmeals. And whoa, check out this glass gem corn, developed by a breeder in Oklahoma. Good for popping and grinding into cornmeal, it's for sale, but in short supply.
So if color doesn't determine sweetness, what does?
Centuries of breeding, chance history, some recent tinkering. At war with Native American tribes in 1779, some American troops came across a field of particularly sweet yellow corn that the Iroquois had been growing, seized it, and began to grow the strain for themselves, making it a forerunner of modern sweet corn. Still, an early problem posed by corn was that it would lose about half its sweetness within 24 hours of picking, becoming more and more starchy. So in the 1800s, American planters began mixing and matching corn characteristics to breed varieties that would stay sweeter longer—meaning the kernels had more sugar. Thus developed the three main strains of corn we see today in the U.S.: normal sugary, sugar-enhanced (which has twice as much sugar as normal sugary), and supersweet (three times as much). Supersweet corn lasts longer off the stalk, but what was lost in the process, flavorwise, is a certain creaminess that characterized the older breeds.
