83A-5 |
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J. C. RAMIREZ-SUAREZ, Meat and Seafood Products Technology, Centro de Investigación en Alimentación y Desarrollo, A.C., Carretera a la Victoria Km. 0.6, Apdo Postal 1735, Hermosillo, Sonora, 83000, Mexico and M. T. Morrissey, Dept. of Food Science & Technology, Oregon State Univ., OSU Seafood Research Lab., 2001 Marine Dr., Rm. 253, Astoria, OR 97103-3420. Thermal processes have been the most common technique to preserve and modify the sensory characteristics of muscle and non-muscle foods. Since heat treatment promotes changes in texture and appearance, there is an increased interest in non-thermal processes such as high pressure processing (HPP). HPP results in a different product with reduced pathogenic and spoilage-causing microorganisms with improved characteristics, yet maintains a fresh or just-prepared appearance. Research looking on the effects of HPP in troll-caught West Coast Albacore tuna (Thunnus alalunga) was undertaken to produce value-added products for opening new markets for this fishery. The objective of this study was to investigate the differences between changes in heat-induced and HPP on albacore minced tuna muscle. High-pressure treatments at 275 and 310 MPa for 2, 4, and 6 min, » 10°C and heat treatment of 90°C for 35 min were run for minced albacore samples. Effects on protein solubility, thermal stability, total sulphydryls and water retention were measured. Treatments reduced protein solubility, with heat showing an 89% reduction versus 60% reduction by HPP. HPP increased the thermal stability of sarcoplasmic and myofibrillar proteins, shifting their endotherms towards higher temperatures but only myosin showed an enthalpy change higher than control. Heated proteins did not show any endotherm peak indicating total protein denaturation, and showed the least total sulphydryl content and the highest water holding capacity. Results showed that while heat promotes complete denaturation of muscle proteins, HPP resembled muscle proteins more in their native state. This process could be used for producing value-added albacore tuna products with minimal protein denaturation and unique sensory characteristics.
Session 83A, Aquatic Food Products: Byproducts, mince and surimi
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