Chemical Treatments to Reduce Off-Flavor in Farm-Raised Channel Catfish (Ictalurus punctatus) Fillet

The efficacy of chemical treatments on reducing musty off-flavor in catfish fillets was evaluated in this work. Two ingredients, tea polyphenols and acetic acid, were found effective on removing the off-flavor. Three treatments, i.e., 0.40 g/L tea polyphenols, 0.50% acetic acid and 0.40 g/L tea polyphenols + 0.50% acetic acid, presented significantly better results than water wash (the control). Mechanism study indicated that the three treatments were able to reduce the contents of geosmin and/or 2-methylisoborneol which are the two major off-flavor causing compounds in catfish fillet. The treatment with both of the ingredients showed slightly better results than the treatment with only one ingredient. Practical Applications: Off-flavor is a major quality concern to farm-raised catfish fillet. Major revenue lose could be caused by delay of harvest and/or defective products due to off-flavor. This study offers a novel strategy to reduce the musty off-flavor by chemical treatment, which could help the catfish industry improve fillet quality and lower production cost. The research indicated that tea polyphenols and/or acetic acid were effective to reduce/remove musty off-flavor in farm-raised catfish after harvest. The two chemicals could reduce the contents of geosmin (GSM) and/or 2-methylisoborneol (MIB), which are the two major off-flavor causing compounds in various fish fillets. Therefore, the treatments developed in this work may also be effective for other seafood products.