49B-26 |
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N. LUDLOW1, H. G. Kristinsson1, M. O. Balaban1, W. S. Otwell1, and B. A. Welt2. (1) Dept. of Food Science & Human Nutrition, Univ. of Florida, 130-B Aquatic Foods Pilot Plant, PO Box 110370, Gainesville, FL 32611-0370, (2) Dept. of Agricultural & Biological Engineering, Univ. of Florida, 111 Frazier Rogers Hall, PO Box 110570, Gainesville, FL 32611-0570 Carbon monoxide (CO) and filtered wood smoke (FS) rich in CO are processes being used to stabilize red color of tuna muscle. There is a lack of information on how these processes affect the quality and safety of tuna. The objective was to perform a comprehensive investigation on how different CO and FS treatments affect various quality and safety parameters of tuna muscle. Fresh tuna loins were aseptically cut in steaks and treated for 48 h (4°C) in different CO/FS environments. The steaks were then vacuum packed and frozen at -30°C. After 30 days at -30°C samples were thawed and removed from the vacuum packs and stored at 4°C in air permeable bags. Changes in color (L, a, b-values), lipid oxidation (TBARS), heme protein oxidation/ligand binding state, texture, water-holding capacity, aerobic microbial growth and histamine formation were measured. CO and FS treatments significantly altered red color of tuna muscle. Red color stability was greatly affected during cold storage after thawing. Color stability was directly related to the amount of CO bound to the heme proteins and their oxidative stability, which was increased on CO/FS treatment. Lipid oxidation was reduced by the CO/FS treatments compared to control. All CO/FS treatments, except 4% CO, led to a reduction in aerobic microorganisms. Only a 100% CO treatment led to a significant delay in microbial growth after thawing. Freezing inhibited histamine formation, while abuse studies indicated that high levels of histamine can form after CO treatment while color is still acceptable. No significant effect on texture and water-holding capacity was found between treatments. At the same CO percentage FS did not show any benefit over a commercial gas mixture. The results indicate that certain CO gas mixtures may extend shelf life of tuna, while the possibility of abuse remains and warrants further research.
Session 49B, Aquatic Food Products: General
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