Partnership could eliminate off-flavor in fish.

USDA/ARS scientists are teaming up with Abraxis Inc. (Hatboro, PA) to help rid fish of offensive off-flavors. Researchers with the ARS Aquatic Animal Health Research Laboratory, P.O. Box 952, Auburn, AL 36831) have signed a two-year cooperative research and development agreement to develop monoclonal antibodies--proteins that lock onto a very specific molecule--that could ultimately be used in a test kit for detecting geosmin in fish ponds and drinking water.

Geosmin is one of several compounds produced by algal organisms that grow in groundwater and soil. It is a major cause of off-flavor. It has an aroma that people typically associate with soil. Another important algal compound that causes off-flavor, methylisoborneol, will not be studied under this agreement.

Geosmin is produced by blue-green algae blooms--pond scum--in ponds and other bodies of water, including catfish ponds. Catfish absorb these compounds, resulting in bad or dirty-tasting fish. To ensure bad-tasting fish don't reach consumers, farmers take their catfish to a processing plant where a taste panel eats and smells a cooked catfish fillet to check for the existence of off-flavor. If the fish fillet tastes bad, the processing plant will not buy the producer's fish. This causes major losses for producers, about $16 million annually in the United States.

Currently, there are no effective, environmentally friendly ways to clean algal blooms in ponds. A geosmin monoclonal antibody could pave the way for more precise water quality tests and other corrective treatments. It would enable catfish farmers to detect geosmin in water and remove the compound before it becomes a fish-farming problem.

Further information. Richard Shelby; phone: [phone]; fax: [phone]; email: [e-mail]. At Abraxis: Fernando Rubio; phone: [phone]; fax: [phone].