Orange Peel Carbohydrates May Have Health-Promoting Properties

Orange peels are an abundant source of carbohydrates that have multiple health-promoting properties, according to in vitro results in a study by an Agricultural Research Service scientist and cooperators.

Arland T. Hotchkiss, a carbohydrate chemist at the ARS Eastern Regional Research Center (ERRC) in Wyndmoor, Pa., and cooperators demonstrated for the first time that pectin, a type of carbohydrate in orange peel, has "prebiotic" properties. These prebiotic carbohydrates, also known as oligosaccharides, are found in certain fruits and vegetables. Prebiotics are nondigestible foods or nutrients that increase the growth of beneficial "probiotic" bacteria in the large intestine. Probiotic bacteria stimulate health and help prevent foodborne pathogen growth.

Prebiotics are beginning to be used in food products and in animal feeds. Pectin is used as a gelling agent in jelly products and to stabilize dairy products. Orange peels are used in cattle feed, but their value is less than 5 cents a pound.

Hotchkiss is with the ERRC Crop Conversion Science and Engineering Research Unit. He collaborated with the University of Reading's Robert Rastall and Glenn Gibson who found this new class of "anti-adhesive" prebiotics, those that prevent pathogens from binding to the intestine.

Brian Kerr, an ARS researcher in Ames, Iowa, is conducting research to determine if this new generation of prebiotics has desirable health benefits in swine production systems.

Hotchkiss and his colleagues are developing novel, cost-effective methods to extract pectic prebiotics. This research could benefit citrus growers and processors by adding value to these citrus-processing byproducts.

ARS is interested in cooperating with a commercial partner to further develop and commercialize this technology. ARS is the chief scientific research agency of the U.S. Department of Agriculture.