Peanut's Oil Extends Shelf Life
of Other Varieties
By Jill Lee
October 17, 1996
RALEIGH, N.C., Oct.
17--Peanuts may keep their flavor longer after being roasted in oil from
peanut lines bred to be high in oleic acid, a U.S. Department of Agriculture researcher said.
"By roasting regular peanuts in oil from high-oleic peanut lines we
saw shelf life improvements of 20 to 30 percent," said plant physiologist
Tim Sanders with USDA's Agricultural
Research Service. "We think this is happening because the high-oleic
oil is more stable than regular peanut oil. Its fatty acids don't break down as
quickly. It's that breakdown that produces off-flavors."
High-oleic peanuts, such as the University of Florida's Sunoleic 95R,
caught Sanders' attention last year. He speculated that roasting regular
peanuts in the oil from high-oleic peanuts could extend the shelf life of
At the ARS Market Quality and
Handling Research Laboratory in Raleigh, N.C., Sanders tested his idea with
peanut varieties commonly grown in Virginia, North Carolina and South Carolina.
The high-oleic oil roasting benefitted all the peanuts tested, but the effect
was pronounced in the smallest peanut size group.
The finding is valuable to industry since the smallest peanut size contains
the highest percentage of immature peanuts. Peanuts in this size class tend to
have a shorter shelf life, Sanders said. He also noted that shelf life
improvements he saw in peanuts are likely to occur in other food products
roasted this way.
"While high-oleic sunflower oil is available commercially, high-oleic
peanut oil is not out in the market yet," said Sanders. "But we
expect these findings to enhance its potential."
Scientific contact: Tim Sanders, Market Quality and Handling
Research, Agricultural Research Service, USDA, Raleigh, North Carolina 27695.
Telephone: (919) 515-6312.