Your Guide to Corn
Your Guide to Corn
It’s the height of corn season, and the summer’s best sweet and crunchy cobs are hitting farmers markets and grocery stores around the country. But corn sneaks into far more than just our produce aisles. In The Omnivore’s Dilemma, Michael Pollan estimates that one quarter of a grocery store’s 45,000 items contains corn—he calls it, “The cornucopia of the American supermarket”—and that number doesn’t exclude non-edible goods like trash bags and batteries. Everything from the insides of a Twinkie to the waxy coating on a cucumber to fresh bakery muffins utilizes corn. Pollan blames what he sees as the dysfunctional American food complex on one culprit: zea mays, otherwise known corn.
That a grain once grown by the Aztecs, Mayans, and Incas has reached such ubiquity in the food chain supply, not to mention an ingredient in everyday objects, is nothing short of amazing. After all, cows eat it; we butter, salt, and pepper it; it can be distilled into whiskey; and it shows up in adhesives like envelope glue! According to the US Department of Agriculture, about 80 million acres of land are planted for corn. And, of all the grains grown in the US, corn accounts for 90% of the total feed grain production and use. There are about 21,000 accessions from the genus Zea, consisting of corn and its direct ancestor, teosinte, in the hands of the USDA. Those other grains might as well waive the white flag of surrender.
But considering how central corn is to our national diet, not to mention economy, most of us don’t know much about the different varieties out there, let alone which ones can be great to eat. From the types of sweet cobs you’ll encounter at the supermarket to the origins of popcorn to all the delicious things you can do with corn starch, hominy, and grits, here’s your complete guide to all things corn.
The Anatomy of a Corn Cob
Corn grows on stalks that usually reach between seven and 10 feet high, though according to Guinness World Records, the tallest recorded plant reached a whopping 35 feet, three inches. Perhaps more interesting than its ability to reach to the sun is its process of pollination. As corn stalks grow, they produce both male and female flowers. The female flowers are ears; the male flowers emerge as a tassel at the top of the plant. For corn to properly mature, the pollen from male flowers must be blown onto the silks protruding from each female ear—each pollinated silk will eventually yield a single kernel of corn. A fun fact for corn lovers: Plants can have between 500 and 1,000 kernels and they always come in an even number of rows. These kernels come in all shapes and sizes. Here are some of the most common varieties.
What most people know as field corn is also called yellow dent corn (Zea mays indentata). It’s so named after the dimple or indent that forms at the top of each kernel when it dries out. Dent corn has a higher starch content and lower sugar content than sweet corn, meaning that no matter how much butter you slather on a freshly picked cob, it’s going to be hard to choke down. Unlike sweet corn, dent corn isn’t picked fresh—it’s harvested at the mature stage when the kernels are dry (though modern farmers sometimes pick dent early and then dry it manually). Dent corn is primarily used in the production of ethanol, as feed for livestock, and to make sweeteners. Tortilla chips, snack foods, and masa can come from yellow dent corn or white dent corn, the latter of which is most often dry-milled for human consumption.
In most parts of the US, fall brings overflowing gourds and piles of what’s usually known as Indian corn or calico corn, a nod to its multi-colored kernels. Flint corn (Zea mays indurata) is named after its texture (as in hard like flint), and has less soft starch than dent corn. Native Americans grew flint corn for its hearty nature and high nutrient value; today heirloom varieties are grown for milling into cornmeal, flour, hominy, and the like. Dan Barber of Blue Hill restaurant at Stone Barns, for instance, grows New England Eight Row Flint for use in polenta. Businesses have popped up seeking to reintroduce lesser used grains such as flint corn. Anson Mills in Columbia, SC, led by grain enthusiast Glenn Roberts, focuses on native heirloom grains, in particular hard heirloom flint corns and soft heirloom dent corns of the pre-industrial era.
The high sugar content of sweet corn (Zea mays convar. saccharata var. rugosa) makes it a favorite at the dinner table. Unlike dent corn, which is picked at the mature stage, sweet corn is picked at the immature or milk stage—squeeze a kernel of sweet corn and “milk” will squirt out. Sweet corn picked extremely early in its growth is marketed as baby corn; these small, tender cobs can be eaten whole.
At most supermarkets, sweet corn is marked simply “corn,” and comes in white, yellow, colored, and multicolored varieties. While there’s rarely varietal information, there are several biggies that proliferate at farmers markets and grocery stores. What we think of as “eating corn” is grouped into three categories: standard corn (also known as normal sugary), sugary enhanced, and supersweet corn.
As with most vegetables, corn tastes best when fresh-picked, but standard corn has an especially short shelf life. Among the most popular standard corn varieties are Silver Queen, renowned for its large ears, sweet taste, and super-white kernels (the queen, really, of sweet corn); Jubilee, popular for its high yield and tender yellow kernels; and Butter and Sugar, which is defined by its mix of white and yellow kernels. Consumers can look for these names when shopping, but their availability tends to be inconsistent.
Sugary enhanced corn is known for having a sweet flavor and slightly longer shelf life. It’s as likely to show up at farmers markets as supermarket shelves. Varieties you might be chowing down on after a grocery run: Silver Choice Hybrid, Kandy Korn, Sugar Buns, and Peaches and Cream.
So-called supersweet corn—hybrid varieties like sugary enhanced—is the sweetest of the sweet corns, and also has an extended shelf life that appeals to outfits shipping to grocery stores, where most of it ends up. Varieties can sound more like porn star names than corn types (Early Xtra Sweet, King Kool), but it’s unlikely you’ll see them actually labeled as such by the time they hit stands.
You can’t just take any old corn kernel, put it in a pan, and expect it to pop. You’ll need a special kind of flint corn with a hard exoskeleton (Zea mays everta), which has been dried to have a certain moisture point (around 14%). When heated, the trapped water turns to expanding steam, which at the right temperature (around 212 degrees) pops the kernel inside out. That steam turns the starch inside the kernel into a gelatinous material, which turns solid when it cools into the delicious crunchy treat we know as popcorn.
There are many varieties of popcorn, but they all pop in one of two shapes—either resembling a mushroom or a snowflake. Mushroom-shaped popcorn usually gets covered in caramel or other liquid sugars (see kettle corn), while the snowflake shape is what you’ll find served in movie theaters and stuck between the couch cushions of homes across the US. At the grocery store, corn varieties sold as popcorn usually look similar, but popcorn does come in a variety of sizes, colors, and even “hulless.” (In truth, all popcorn has hulls, but the hulls on some smaller varieties explode right off, leaving little of the original hull on the popped kernel.)
According to Roberts of Anson Mills, there were “likely five to seven times the amount of maize varieties” during the time when “Indians were gifting corn to the new settlers.” As industrialized farming and hybrids have become the norm, diversity in corn decreased dramatically. Still, even with the decrease, “there are blizzards of possibilities” with corn, he say—both in different types of corn and in what you can do with it. “The flavor profiles are so distinct when we’re not goofing around with it.” Of course, to find much in the way of heirloom corn varieties today, you’ll likely have to go to a specialty grocery store that stocks grains ground at old-fashioned gristmills, shop online, or grow your own.
Is it corn or a nut? It’s corn, and traditionally corn nuts are made from a Peruvian corn calledchoclo. The large-kernel corn gets soaked in water for several days to bring them back to size, and then are toasted or deep-fried and salted as a snack. The CornNuts brand covers its very own hybrid corn in flavors such as chile picante con limon and ranch.
What to Do With Corn
The Fresh Stuff
There are countless ways to enjoy sweet corn, but the grill’s never a bad place to start. Check out our tips for the three easiest ways to grill corn or just jump to the best basic grilled corn. We also like it slathered in crema, salty cotija cheese, and chili powder for elotes (Mexican street corn). But the grill’s just the beginning. Sweet corn is great mixed into salad or evenpuréed into a creamy chilled soup. You can find some of our favorite recipes right here.
Grab a Bag of Cornmeal
Cornmeal is basically just dried and ground corn. Generally speaking you’ll find either “regular” cornmeal, which has been ground relatively fine between metal rollers, or stone-ground cornmeal, which has a coarser texture and typically retains more nutrients. But within those categories, it comes in countless different textures, and can be made from a pretty wide variety of corn types and colors. Most of us know and love it as the main ingredient in cornbread, but it’s also the central ingredient behind polenta. You can whip your polenta up rich and creamy; serve as a base for sauces or grilled steak and tomatoes; chill, slice, and fry it into cakes; or even use it in place of noodles in a hearty lasagna-style casserole.
What, you ask, is this nixtamalization business? In short, it’s a culinary limewater solution, or alkali, treatment applied to dried corn kernels. The process gives the corn a more distinctive flavor, helps our bodies process more of its nutrients, and crucially allows the ground cornmeal to react with water to form doughs—something regular cornmeal can’t do with water alone.
Nixtamalized corn is sold in many forms, under a variety of names, but you probably know it best as hominy. Fresh hominy (typically sold in cans) makes its way into soups and stews likeposole, but the dry stuff can also be ground into cornmeal, grits, or masa harina.
Masa’s a remarkably versatile ingredient, and you can get your hands on it at most Latin American groceries. Once you have it, use it to make your very own tamales from scratch, whip up some extra-fresh, flavorful tortillas, gorditas, Salvadoran pupusas, or make an easy as, well, pie. Tamale pie to be precise.
Masa’s great for more than just classics, though: we love it in this masa-based twist on matzo ball soup or your Mexican atole of choice, rich and creamy hot drinks thickened with—you guessed it—masa.