89A-35 |
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L. HUO, Univ. of Florida, Dept. of Food Science & Human Nutrition, 130-B Aquatic Foods Pilot Plant, PO Box 110370, Gainesville, FL 32611-0370 and H. G. Kristinsson, Dept. of Food Science & Human Nutrition, Univ. of Florida, 130-B Aquatic Foods Pilot Plant, PO Box 110370, Gainesville, FL 32611-0370. Carbon monoxide (CO) and filtered smoke (FS) are used to stabilize red color of fish muscle. This color stabilization comes from binding of CO to heme proteins. There is a great need to find simple and rapid methods to determine if fish products have been treated with CO or FS. The objective was to investigate and develop a simple method to detect CO treated products based on the spectral characteristics of extracted heme proteins. A model system consisting of tilapia hemoglobin (Hb) and washed tilapia muscle was constructed to find conditions to optimally extract CO-Hb. Different forms of Hb were produced (Oxy-Hb, CO-Hb and MetHb) and mixed to construct a standard curve based on heme peak absorbance wavelength. CO-Hb was added at different concentrations at different pH values to the WTM and extracted and Hb recovery (by measuring protein content and with SDS-PAGE) and CO binding state (from visible spectra of Hb extracts) determined. Different seafoods were also treated with various CO and FS gases to test the extraction method. Using the model system we were able to find the optimal conditions to extract CO-Hb and maintain its stability. The overall procedure was less than 30 min and could be done at room temperature. Higher CO-Hb recoveries and stability were found when Hb was extracted at pH 8 vs. pH 6. More CO-Hb was recovered at high Hb additions vs. low additions. The method could be successfully used to identify products treated with CO when it was tested on several treated seafoods. As a result of this study it is possible to rapidly detect seafoods treated with CO or FS, which will be an important tool for the industry as well as inspection agencies. More work is in progress to improve the technique and develop more rapid tests.
Session 89A, Aquatic Food Products: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |