Great Expectations for Pectin
McGinnis February 13, 2007
To boost profits for sugar beet growers and processors, Agricultural
Research Service (ARS) scientists are
developing new processes to efficiently isolate beet pectin and associated
polysaccharides and find profitable uses for them.
Pectin, which can be found in the cell walls of fruits and vegetables,
is a polysaccharide, a large molecule made up of many simple carbohydrates
(sugars) linked together. It is often used as a gelling agent and fat
Most commercial pectin is extracted from citrus peels, but sugar beet
pulp is an untapped source with great profit potential. Every year, U.S.
processors generate about 1.5 million tons of dry beet pulp, most of which is
sold for little profit as animal feed. ARS researchers are investigating how
the chemical features of sugar beet pectin could expand the pulp market.
They have also found ways to improve the extraction process.
Extracting pectin from plant material takes an hour or more using conventional
heating methods. To save time and reduce cost, chemist
L. Fishman, who retired from ARS and is now a collaborator at the
Eastern Regional Research Center, Wyndmoor, Pa., developed microwave and
steam-injection techniques to heat fruit peels with acidified water in
pressure-resistant containers. These methods can extract high-quality pectin
within 10 minutes, using less energy.
How will this pectin be used?
In one study, ARS chemist
Liu developed material from pectin and other natural polymers that can be
used in biomedical supplies, such as prosthetic devices and scaffolding for
tissue repair. In another study, plant physiologist
T. Hotchkiss, Jr. and cooperators demonstrated that pectin fragments from
orange peel could promote health by increasing the growth of beneficial
probiotic bacteria in the large intestine.
about the research in the February 2007 issue of Agricultural Research
ARS is the U.S. Department of
Agriculture's chief scientific research agency.