49B-20 |
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R. S. RASMUSSEN, S. Carroll, T. Okada, 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 Albacore tuna (Thunnus alalunga), harvested off the California, Oregon, and Washington coasts throughout the summer and early fall, are primarily sold as a canned product in foreign and domestic markets. The potential for alternative marketing for troll-caught albacore is favorable due to its sustainability, low bycatch, high protein content, and high omega-3 fatty acid content. Since the market value of albacore is influenced by its lipid content, the objectives of this study were to determine how intrinsic factors such as seasonality, geographic area and size affect total lipids in the muscle. Two hundred and thirty-nine albacore tuna were troll caught off the West Coast of the U.S. from June to October, 2003 and were measured for size and analyzed for lipid content by standard AOAC proceedures. The average weight of the albacore was 6.07 kg, with a range of 2.46 kg to 11.62 kg. The percent lipid was found to increase slightly in fish caught later on in the season (R2=0.23). Geographical Information Systems (GIS) software is used to determine spatial autocorrelations between % lipid and geographic location. Although the lipid content varied considerably among tuna caught at similar latitudes, albacore caught at lower latitudes tended to have lower lipid content. Most of the fish caught below 40 degrees north had a lipid content of less than 10% while higher-fat fish (13-19% lipid) were all harvested above 40 degrees north. The lipid content was highly variable, averaging 8.57% lipid and ranging from 0.67% to 18.74%. The moisture content ranged from 56.93% to 73.07%, with an average of 65.17%. There was a strong inverse correlation between the lipid and moisture content of the albacore (R2=0.93). The high variability in lipid content presents opportunities and challenges as the industry looks to alternative marketing for albacore and albacore products.
Session 49B, Aquatic Food Products: General
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