Folks around the country are already enjoying one of summer’s best perks – sweet corn season! The tasty treat comes out of the field a few months earlier than dent corn. Dent corn, also referred to as “field corn,” is the type of corn that the USDA reports on and underpins commodity futures contracts. According to the National Corn Growers Association, dent corn accounts for approximately 99% of all corn production in the US. While processed dent corn can also be used in human food products such as breakfast cereals and tortillas, the type of corn most humans consume in its solid-kernel form is “sweet corn”.
As the name implies, sweet corn has a higher sugar content than field corn and is harvested while still immature, before the sugar can turn into starch. This is the summertime favorite served on the cob at backyard BBQs, as well as the fresh, frozen, and canned varieties found in grocery stores.
Open-pollinated cultivars of white sweet corn became widely available in the United States in the 19th century. Today, there are three main classes of sweet corn based on different gene mutations that are responsible for giving corn its sweetness – “standard sugary”, “sugar enhanced”, and “shrunken-2”. There are also new hybrid varieties continually being released, bred from the combined genetics of those sweet corn types, sometimes called “synergistic” varieties.
There are hundreds, if not thousands, of sweet corn cultivars available today. Two of the most enduring are “Country Gentleman”, introduced in 1890 by S.D. Woodruff & Sons, and “Stowell’s Evergreen”, an heirloom variety that dates back to the mid-1800s. While most varieties are white or yellow, corn comes in a rainbow of colors, including black, red, blue, purple, green, and even pink. Wide bicolor varieties offer both white and yellow kernels, but there are a multitude of other combinations. There are also multicolored varieties that can include the whole rainbow.
Sweet corn may have more sugar than field corn, but it’s a surprisingly small amount – there are only 5 grams of natural sugar in a medium-sized ear of corn, per the USDA. An ear of sweet corn has less than a third of the sugar in a banana and only about one-fifth the sugar of a medium apple. There also are a surprising number of myths about sweet corn’s nutritional benefits that just won’t go away. Some that need debunking:
Humans Can’t Digest Corn: Corn kernels are actually seeds. The interior of the kernel holds the germ, or corn embryo. The germ is surrounded by a starchy food supply (endosperm) that feeds the seed after it germinates. This is the tasty and nutritious part. The kernel’s protective outer shell, or hull, however, is a waxy coating of cellulose that’s tough enough to withstand the human digestive system. That’s why the casing of the corn kernel passes through your system looking fully intact. The inside of the kernel, however, does break down in your stomach and intestines, allowing you to absorb nutrients.
Corn Has No Nutritional Benefits for Humans: Sweet corn does indeed have numerous health benefits. It’s a good source of fiber, which helps provide a feeling of fullness and is important for digestion. It is also a good source of B vitamins, including folate, an important vitamin for pregnant women, and has healthy amounts of iron, protein, and potassium.
Cooking Corn Robs It of Nutrients: In general, cooking vegetables can change the levels of different nutrients, but different cooking methods have different effects. Water-soluble vitamins, such as B and C, are the most sensitive to cooking methods. These vitamins have a tendency to leach out of veggies when boiled — and can be degraded by heat. Fat-soluble vitamins, such as A, D, E, and K, fare better during the cooking process. When it comes to minerals, heat can improve the ability of some to be digested, absorbed, and metabolized.
Frozen and Canned Corn is Less Nutritious: You can enjoy sweet corn all year round knowing that even the frozen and canned varieties that we resort to in winter usually closely match the nutrient content of their fresh counterparts. Some vegetables are flash-frozen shortly after harvest, a time when their nutritional content is highest. In general, vitamins and minerals are unchanged by the canning process. However, canned veggies may have fewer water-soluble vitamins, such as B and C. (Sources: Texas Farm Bureau, Mississippi State, USDA, Cleveland Clinic)
