89A-15 |
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Y. YAGIZ, H. G. Kristinsson, M. O. Balaban, and M. R. Marshall, Jr. Dept. of Food Science & Human Nutrition, Univ. of Florida, 359 FSHN Bldg., Newell Dr., PO Box 110370, Gainesville, FL 32611-0370 High pressure processing (HPP) is becoming a promising seafood preservation method. Very limited information exists on the influence of high pressure on the oxidative stability and quality changes of fish muscle. The objective was to investigate the effect of different pressures on the quality changes of rainbow trout (a fresh water species) and mahi mahi (a salt water species) during cold storage. Skinless fillets were treated at different pressures (150, 300, 450, and 600 MPa for 15 min) initially at room temperature, stored at 4° C and analyzed at 1, 3, 6 d of storage. The red muscle was analyzed for lipid oxidation by measuring thiobarbituric reactive substances (TBARS). Whole muscle was analyzed for total aerobic count. Images of the fillets were captured using a color machine vision system equipped with a video camera and average color parameters (L*, a* and b* values), distribution of hue values (0-360) and % color composition were calculated.A pressure of 300 MPa inactivated the initial microbial population in rainbow trout (6 log reduction). However,inactivation of the initial population on mahi mahi was only about 4 log reduction at the same pressure. Microbial growth was significantly retarded after HPP. The color results showed that the redness (a* value) of rainbow trout at 300 MPa and above was significantly (p<0.05) decreased compared to mahi mahi. TBARS values for rainbow trout increased as pressure increased. The same TBARS trend was not seen for mahi mahi; maximum oxidation was found at 300 MPa and then declined. The optimum HPP conditions that influence lipid oxidation, microbial load and color changes were found to be 300 MPa for rainbow trout and 450 MPa for mahi mahi. These parameters demonstrate the usefulness of HPP in seafood processing and the influence of species variation on processing parameters.
Session 89A, Aquatic Food Products: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |