Nancy Nichols, Bruce Dien and colleagues are investigating the potential for
using field peas to produce ethanol. Here, in an earlier study of certain corn
hybrids, Nichols and Dien add yeast to a bioreactor to begin ethanol
fermentation. Click the image for more information about it.
ImagineFuel Alcohol From Pea Starch!
Suszkiw March 28, 2006
So you dont like eating peas? Then how about fueling your car or
truck with them? Thats a possibility Agricultural Research Service (ARS) scientists are exploring--using a type
of fuel called ethanol, made from the legumes starch.
Ethanol is among the cleaner-burning alternatives to petroleum, and is
credited with reducing tailpipe emissions of carbon monoxide and other
pollutants when added to gasoline.
In 2004, some farmers contacted ARS microbiologist
Nichols about new ways to add value to their field pea crops. Most peas
grown in the northern United States and elsewhere are fed whole to animals as a
rich source of protein. The remainder is sold for human consumption as split
peas. Besides protein, field peas also contain lots of starch. The farmers
thought they might earn more if the crops starch could be used to make
ethanol for fuel, while still using the leftover protein as high-value feed for
To find out, Nichols teamed with
Dien, a chemical engineer; Victor Wu, a chemist (formerly with ARS, now
Cotta, a microbiologist--all at ARS
Center for Agricultural Utilization Research, Peoria, Ill. There, they put
whole peas through a three-step process.
First, they dry-milled the peas into flour. Next, they separated the
protein and starch. Finally, they used enzymes and yeasts to ferment the
starchs sugars into ethanol.
During studies, the fermented pea starch produced somewhat less
ethanol than corn (1.7 gallons per bushel versus 2.8), because the legume had
less starch to begin with. But the pea starch fermented just as easily as corn
starch. Potentially, the high yield of enriched protein, together with the
fermentation leftovers, could be sold as livestock feed.
Economic modeling studies are now under way to determine whether using
pea starch could be profitable to commercial ethanol plants, especially those
located in areas where the legume is grown.
ARS is the U.S Department of
Agricultures chief scientific research agency.