Should You Throw Away a Corn Cob?

A corn kernel is attached to the cob at its base, and when it is cut off with a knife, the bottom of the kernel remains on the cob. This leftover part is the juiciest and most starchy part of the kernel; the cob itself is also moist and sweet when the corn is fresh. When the kernels are cut off and the cob is discarded, some of the corn’s flavor goes with it. The cob’s woody texture is not edible, but the milk and starch it carries can be collected separately. A dried cob no longer contains this milk and adds only a woody flavor to water.

The first method is scraping. Stand the cob with the kernels cut off upright in a wide bowl, and rub the dull back of a knife down it from top to bottom. The kernel bases left on the cob and a creamy white liquid will fall into the bowl. Add this liquid to corn soup, corn fritter or bread batter, or corn cooked in a pan; it gives them a rich, sweet consistency. Do not use the sharp edge of the knife; it will cut the cob fibers too and mix hard pieces into the liquid. Turn the cob and scrape each side separately.

The second method is simmering. Break the scraped cobs into two or three pieces and add them at the beginning of cooking to the pot of soup or vegetable stock, since it takes time for them to release their flavor. As they simmer, the cobs add a sweet flavor and a little body to the liquid; this creates a depth from the soup’s own ingredients, especially in corn soup. The cob is not eaten, so strain it out when cooking is finished. If you will blend the soup, remove the cobs first; their fibers can wrap around the blade and mix into the soup like wood splinters.

There is a similar opportunity when boiling corn on the cob. The corn releases some sugar and starch into the boiling water, making it slightly sweet. Taste the water; if it tastes sweet, use it as the liquid for corn soup or rice. If you plan to cut the kernels off boiled corn with a knife, the remaining cob can also be simmered and strained, but it releases less milk than a raw cob because some of its milk has already gone into the boiling water. Use the boiling water and the cob together.

There are limits to using the cob this way. A dry, hard cob has lost its sweetness and gives the water a woody flavor when simmered. Do not use a cob that is moldy, darkened, or smells sour. Canned or frozen corn does not come with a cob; this method applies only to fresh corn sold on the cob. When buying fresh corn, check that the cob’s cut end is moist; a dried-out end indicates that the corn has been stored for a long time and that the cob has lost some of its milk. Corn used on the day it is purchased is also at its sweetest.