89A-6

C. KAEWPLANG¹, J. L. Silva¹, and W. Holmes². (1) Dept. of Food Science, Nutrition & Health Promotion, Mississippi State Univ., 110 Herzer Bldg., Mailstop 9805, Mississippi State, MS 39762-9805, (2) Mississippi State Chemical Lab, Mississippi State U.`, Box 9572, Mississippi State, MS 39762

Off-flavor incidents in catfish are caused mainly by two chemical compounds, 2-methylisoborneol (MIB) (musty) and geosmin (earthy). These off-flavors result in major losses of catfish production in the warmer months of the year. The objective of this experiment was to test various compounds for their ability to decrease or eliminate off-flavor in catfish during processing. Three diffusion methods (dipping, injecting and tumbling) with 0.5% H₂O₂ were studied. Afterwards, the effect of concentrations of acetic acid (0%, 0.2%, 1%, and 2%) and carbonated drinks (Sprite®, Seven-up®, and commercial carbonated water) on off-flavor of catfish fillets were investigated. Sensory evaluation based on intensity of off-flavor was performed utilizing a 5-point hedonic scale. There were no differences in diffusion treatment, so dipping was chosen for further experiments. For odor of fresh fillets, there were no differences between 0% and 0.2% acetic acid, while 1% and 2% acetic acid decreased off-flavor but induced a sour taste. Commercial carbonated water was not an effective off-flavor reducer. Reductions in off-flavor were obtained using Sprite® and Seven-up®. For cooked fillets, 2% acetic acid was shown to reduce off-flavor more than lower concentrations. Seven-up® presented the best result compared to control, commercial carbonated water, and Sprite®. The high intensity citrus flavor (lemon, lime), resulted in additional acceptability by the panelists. The addition of certain oxidizing and/or masking compounds may be promising in alleviating the off-flavor problem in processed catfish, thus preventing consumer rejection and loss of markets.

Session 89A, Aquatic Food Products: General
2:00 PM - 5:30 PM, Tuesday PM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana