USDA Scientists Find Treasure in
By Jill Lee
December 12, 1996
DAWSON, Ga., Dec.
12--Peanut blanching mills sell peanut skins as animal feed for less than a
penny a pound. But this red, papery by-product may have a new use in some hair
conditioners and cosmetics, a U.S. Department of
Agriculture scientist says.
Chemist Richard J. Cole said studies of peanut skin oil have identified a
fatty acid--behenic acid--that is often used to give hair conditioners and
moisturizers their smoothing properties.
"We found peanut skins had up to 17 percent oil, a potentially
valuable extract in itself at 43 cents a pound," said Cole of the USDA's
Agricultural Research Service."But
we were curious about a waxy substance that settled out at the bottom of our
oil samples. When we analyzed it further, we discovered it was long-chain fatty
acids, including behenic acid."
Behenic acid currently is extracted from rapeseed flour and sells for about
$8 a pound, depending on its purity. It's used mainly in make-up and natural
A ton of peanut skins could yield as much as 13 pounds of long-chain
saturated fatty acids, mainly behenic and lignoceric. A typical U.S. peanut
mill produces about 17 tons of skins per week.
Cole said the behenic and lignoceric acids were discovered when a visiting
Russian scientist, Victor Sobolev, tried to create new products from the skins.
He and Cole did the studies at ARS'
Peanut Research Laboratory in
Sobolev saw the waxy precipitate in the bottom of his oil samples and
decided to analyze it using gas chromatography. He is now researching the fatty
acids on a two-year assignment at the lab. He said the high levels of behenic
and lignoceric acid in the skin oil offer potential commercial uses, but costs
such as processing and handling will have to be considered.
Sobolev said one possibility is to see if the combination of fatty acids
found in the oil has moisturizing properties beyond those of behenic acid.
Based on standard laboratory extraction procedures, a ton of peanut skins
yields up to 160 pounds of oil before roasting. Roasting the skins boosts the
oil yield to 340 pounds, but adversely alters the fatty acids, eliminating them
as a revenue source.
Scientific contact: Richard J. Cole and Victor Sobolev,
Peanut Research Laboratory,
Agricultural Research Service, USDA, Dawson, Ga. 31742; phone (912) 995-4441,
fax (912) 995-7416, email@example.com; firstname.lastname@example.org.