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Waste not CORN

Minnesota is a “corny” state —growing about one billion bushels of the grains every year.Almost half of Minnesota’s corn crop is exported, andanother 20 percent feeds the state’s livestock. About 15percent of the corn crop is refined into hundreds ofdifferent industrial and consumer products, including food,cosmetics, solvents, textiles, cleaning products andplastics. An equal amount is made into ethanol.


Minnesota now produces about 550 million gallons of ethanola year. The transportation fuel consumes one-sixth of the state’s corn crop, and that couldrise to one-quarter by 2010. Today nearly all gasoline soldin Minnesota is blended with ethanol.


A 56-pound bushel of corn produces about 2.7 gallons ofethanol and 17 pounds of distiller’s dried grains withsolubles, or DDGS. Minnesota produces more than one milliontons a year.

Cow chow

DDGS used to be a low-quality product, without much value.But Minnesota’s “new generation” ethanol plants makehigh-quality DDGS that are in demand to feed cattle, dairycows, swine, poultry — even fish. But that’s not all thiscoproduct is being used for.

Good licks

A Morris ethanol plant is pressing DDGS into protein lickblocks to supplement forage diets for cattle, horses, elkand dry cows.

Piggy provender

Corn solids, called solubles, remain in the ethanolprocessing water. These solubles can be dried and used tofortify baby pig feed.

Nutrition bits

DDGS can be broken out into components such as amino acids,proteins and specialty sugars, for use in medicines andfoods, including low-cal sweeteners, nutritional drinks andweight loss products.

Packing heat

DDGS can be pressed into fuel pellets and burned in pelletstoves or gasified.

Tiny bubbles

Ethanol processing generates carbon dioxide, which is usedto carbonate beverages, make dry ice, and flash freeze meat.

High spirits

High-grade ethanol is used in beverages, such as ShakersOriginal American Vodka, made by Chippewa Valley EthanolCompany in Benson. High-grade ethanol is also used insolvents, cleaning products, cosmetics and medicines.


It’s known as corn trash — the stalks, leaves, husks andcobs that ordinarily end up back on the field aftercombining — but don’t call it garbage. One researcher likenscorn stover to “a barrel of crude oil.” U.S. farmers producethree tons of stover per acre of corn, and this abundancehas sparked many creative efforts to find profitable uses.

Heating fuel

Shelled corn has long been used in home heating stoves. Cornstover also makes a good heating fuel. The University ofMinnesota Morris plans to gasify corn stover to heat andcool the college campus. Corn stover is also being turnedinto pellet fuel for home pellet stoves. Someday, cornstover energy could be used to generate hydrogen for fuelcells.


Corn stover’s potassium and phosphorous remain after burningand can be used as fertilizer.

Comfy cushions

Corn stalks make comfortable cattle feedlot bedding. Incompost dairy barns, corn cobs are a soft substitute for wood-chips.

Resting rugs

Rigid, disposable corn-stalk mats for hog nurseries andfarrowing crates are a renewable alternative to rubber mats,which have to be disinfected between uses.

Mulch mats

Fiber mats for soil erosion-control, mulching and seedingare being made from corn stover and other crop residues.

Spill soakers

Corn stover is useful for soaking up liquids in absorbentproducts such as oil filters and oil-absorbent blankets andmats.

Paper pulp

Corn stover and other ag fibers, such as beet pulp, wheatstraw and barley straw are replacing wood pulp in paper,oriented strand board, and composite building materials.

Renewable polymers

Corn stover and many other kinds of ag fibers can be refinedfor biodegradable polymers, which are used in plastics,packaging films, foams, adhesives and many othermanufactured goods. The processing has not yet beencommercialized, but scientists like the University ofMinnesota’s Roger Ruan say it’s just a matter of time.

Tomorrow’s hydrocarbons

Today, Minnesota’s ethanol plants use just the corn kernelto make alcohol, but it’s also possible to make ethanol fromcrop residues, like corn stover.