Marine Subsidies in Freshwater: Effects of Salmon Carcasses on Lipid Class and Fatty Acid Composition of Juvenile Coho Salmon

Returning adult salmon represent an important source of energy, nutrients, and biochemicals to their natal streams and may therefore have a quantitative effect on the energy levels of stream-resident salmonids. We tested this hypothesis by constructing simulated streams for coho salmon Oncorhynchus kisutch to which we added 0, 1, and 4 carcasses/m2 (0, 0.71, and 2.85 kg wet mass/m2) of pink salmon O. gorbuscha. After 60 d we evaluated the lipid class and fatty acid composition of rearing coho salmon from the simulated streams; the lipid content and triacylglycerols of the coho salmon increased with increasing carcass density whereas phospholipids
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Alaska King Crab: Fatty Acid Composition, Carotenoid Index and Proximate Analysis

Proximate analysis, carotenoid index, and fatty acid composition of the lipids were determined on five separate types of cooked and frozen king crab meat. Similar fatty acid content was found in all types of meat. Eight fatty acids (16:0, 16:1, 18:0, 18:1, 20:1, 22:1, 20:5 and 22:6) accounted for about 77% of the total fatty acid content; 26 others were found in low quantities. Fatty acid 20:5 was predominant acid (20.0–29.5%) followed by 18:1 (15.0–17.1%) and 22:6 (10.2–11.2%). Polyunsaturated acids were predominant (50.2–56.4%) in all types of meat followed by 29.8–33.5% for monounsaturated acids and 14.6–17.0% for saturated acids. Proximate
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Lipid Composition of Alaska Pink Salmon (Oncorhynchus gorbuscha) and Alaska Walleye Pollock (Theragra chalcogramma) Byproducts

In Alaska, over one million metric tons (MT) per year of fish processing byproducts are produced. The objective of this study was to determine the fatty acid profile and quantitate lipid classes in the extracted oils of byproducts from pollock (heads, frames, viscera, skins) and salmon (heads, viscera). In pollock, viscera had the highest percent lipid and in salmon, heads had the highest lipid content. All fish parts from both salmon and pollock were rich in omega-3 fatty acids, which ranged from 25% to 36% in the extracted oils. Differences among byproducts in fatty acid content and percent of lipid
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Nutritional composition and sensory attributes of Alaskan flatfishes compared to plaice (Pleuronectes platessa)

Proximate composition, fatty acids profiles and other nutritional values were evaluated for fillets of Limanda aspera (yellowfin sole), Lepidopsetta bilineata (southern rock sole) and Lepidopsetta polyxystra (northern rock sole) and compared to North Sea plaice (Pleuronectes platessa). Additional information is given on the composition of fillets from arrowtooth flounder (Atheresthes stomias). Plaice (0.8% lipid) and Alaska soles (1.0–1.2% lipid) can be classified as lean species, resulting in low 0.3–0.5 g ∑EPA+DHA/100 g muscle, although the fatty acid profiles of the extracted lipids were characterised by high amount of n-3 fatty acids (33.2–47.3%). Arrowtooth flounder belong to the medium-fat species (4.3%).
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Stabilizing Oils from Smoked Pink Salmon (Oncorhynchus gorbuscha)

Smoking of meats and fish is one of the earliest preservation technologies developed by humans. In this study, the smoking process was evaluated as a method for reducing oxidation of pink salmon (Oncorhynchus gorbuscha) oils and also maintaining the quality of oil in aged fish prior to oil extraction. Salmon heads that were subjected to high temperatures (95 °C) during smoking unexpectedly produced oils with fewer products of oxidation than their unprocessed counterparts, as measured by peroxide value (PV), thiobarbituric acid reactive substances (TBARS), and fatty acids (FA). Higher temperatures and longer smoking times resulted in correspondingly lower quantities of
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Chemical Composition and Texture of Commercial Geoduck Clams (Panopea abrupta) Harvested in Southeast Alaska

The objectives of this study were to determine chemical composition of the siphon and the mantle of commercialsize geoducks clams harvested in Southeast Alaska, and to measure textural differences between the two muscle tissues, comparing them with their frozen counterparts. Live geoducks were processed using standard industry practices and analyzed either fresh or after 90 days of frozen storage. The mantle significantly differed in composition and texture from the siphon. The mantle had significantly higher contents of carbohydrates and lipids, whereas the siphon had a higher moisture content. Protein content was similar between tissues, but soluble protein content in the
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Quality of Alaskan Maricultured Oysters (Crassostrea gigas): A One-Year Survey

The objective of this project was to provide relevant information to Alaska shellfish growers regarding the intrinsic quality of their farmed oysters. A 1-y study was conducted to determine the condition indices, proximate composition, fatty acid content, and microbial load of commercially harvested oysters from 3 different mariculture regions in the state of Alaska. Oysters from farms located in the regions of Prince William Sound, Kachemak Bay, and Southeast Alaska were sampled according to the farmers' harvest schedules. Our results suggest that Alaskan maricultured oysters have slight seasonal and regional differences. The condition indices of Alaska oysters were high, indicating
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