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Nagging Question
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If Corn on the Cob Is So Low in Fat, Where Does Corn Oil Come From?It’s a big fat mystery |
If corn on the cob is so low in fat, where does corn oil come from?
The corn used to make most oil is yellow dent corn, also called field corn—a different variety than the sweet corn you find at the grocery store. A medium ear of dent corn has about 4.74 grams of fat. Most of that is contained in the germ, the innermost part of the kernel. (A medium ear of sweet corn has about 1.06 grams of fat, though it still qualifies as low fat under FDA guidelines.)
It takes a lot of corn to make corn oil. A 56-pound bushel yields 1.6 pounds, or about 700 milliliters, of oil, says Shannon McNamara, spokeswoman for the Corn Refiners Association.
In corn refining , the kernel is separated into its component parts: the fiber-rich outer hull, the starch-and-protein-rich endosperm, and the oil-rich germ. To do this, the kernels are steeped in slightly acidified water, which loosens the hull and makes the endosperm swell up; then they’re ground coarsely. A centrifuge removes the lighter germ from the rest of the corn. The remaining grounds are passed through a series of screens. The endosperm, which grinds into small particles because it’s soft, passes through the screens. The larger pieces of hull stay behind.
After being cleaned and dried, the germ is pressed to extract the oil, much in the same way olives or canola seeds would be. Most producers then use a solvent such as hexane to extract more oil from the pressed germ.
At this point, the oil is called crude corn oil and is dark yellow with a strong corn smell and taste. It’s filtered, bleached, and cleaned to purify it, resulting in the light-yellow, neutral-smelling refined corn oil you’ve got in your pantry.

























What is done with the remains of the corn after the oil is extracted? Which country produces the most corn oil that we see in our North American grocers? Can corn oil that is not purified be bought and used for anything?
Maxmillan:
The hull and what's left of the germ after pressing are turned into animal feed, and the starch from the endosperm ends up as all sorts of stuff used in processed foods--modified cornstarch, high-fructose corn syrup, maltodextrin, etc.
The US produces most of our own corn oil, since we grow so much corn (thanks to government subsidies, but that's a whole different story).
Crude corn oil is sometimes used for animal feed too, but most of it is refined. I'm pretty sure it's not ever sold to consumers, and I don't think it would be very useful even if it was.
I'll have to admit I"m curious about the crude corn oil. It might have good flavor for some dishes.
Problem is, the chemicals that give it all that flavor and color also make it go rancid quicker.
Read the Omnivore's Dilemma. The first section of the book is dedicated to America's obsession with corn. It also goes into a detailed step by step description of how we get high fructose corn syrup, glucose, stuff to pave roads and many other randow derivatives of corn.
What about grapeseed oil? When I eat seeded grapes, should I make sure not to swallow the seeds, because they're fatty?!