Cause of musty flavor in pond-cultured penaeid shrimp

Abstract

In 1983, pond-cultured penaeid shrimp imported into the United States from culture ponds in Ecuador were found to have an intense earthy-musty flavor which made them unmarketable. High concentrations of geosmin ( trans, 1,10-dimethyl-9-decalol), a musty odorous compound, were found in the tail muscle of the shrimp. The level of geosmin, 78 μg/kg muscle, was much higher than levels found in earthy-musty flavored freshwater channel catfish from culture ponds in the United States, which is around 9.8 mg/kg. Cause of the rare occurrence of off-flavor in the shrimp is hypothesized to be reduction in salinity in the coastal culture ponds which allowed growth of geosmin-producing blue-green algae.