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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Purification and Characterization of Pepsin-Solubilized Collagen from Skin and Connective Tissue of Giant Red Sea Cucumber (Parastichopus californicus)

Pepsin-solubilized collagen (PSC) was extracted from giant red sea cucumbers (Parastichopus californicus) and characterized for denaturation temperature (Td), maximum transition temperature (Tm), enzyme-digested peptide maps, and gel-forming capability. SDS-PAGE showed that PSCs from giant red sea cucumber skin and connective tissue were both type I collagens, consisting of three α1 chains of approximately 138 kDa each. The amino acid composition and peptide maps of PSCs digested by V8 protease were different from those of calf skin type I collagen. The Td and Tm are 18.5 and 33.2 °C, respectively, for skin PSC and are 17.9 and 32.7 °C, respectively, for
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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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Evaluation of supplemental fish bone meal made from Alaska seafood processing byproducts and dicalcium phosphate in plant protein based diets for rainbow trout (Oncorhynchus mykiss)

We report performance of rainbow trout (Oncorhynchus mykiss) fed a balanced dietary mix of plant proteins supplemented with either fish bone meal (FBM) derived from Alaskan seafood processing byproducts or dicalcium phosphate. Seven experimental diets were formulated to contain two levels of dicalcium phosphate or two levels of two different kinds of FBM in all plant-protein (APP) based diets as follows: Diet 1, FM based; Diets 2 and 3, APP diets with low or high dicalcium phosphate; Diets 4 and 5, APP diets with 4% or 8% low phosphorus FBM; and Diets 6 and 7, APP diets with 2.7% or
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Characterization of rheological and physicochemical properties of Alaska walleye pollock (Gadus chalcogrammus) roe

Alaska walleye pollock (Gadus chalcogrammus) roe is a commercial product of the Alaska pollock fishery. Accordingly, the objective of this study was to determine functional properties of pollock roe through rheological and physicochemical analyses. Pollock roe rheological properties were determined by flow sweep and frequency sweep measurements. Zeta potential of the roe was measured at different pHs (2-12) and roe protein concentration of 0.05% (w/v). Protein solubility was determined by adjusting pH of the freeze-dried pollock roe powder between 2 and 12. Emulsion stability of the roe was determined by measuring creaming index at different oil:water ratios ranging from 5:95
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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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Development of a method to produce freeze-dried cubes from 3 Pacific salmon species

Freeze-dried boneless skinless cubes of pink (Oncorhynchus gorbuscha), sockeye (Oncorhynchus nerka), and chum (Oncorhynchus keta) salmon were prepared and physical properties evaluated. To minimize freeze-drying time, the kinetics of dehydration and processing yields were investigated. The physical characteristics of the final product including bulk density, shrinkage, hardness, color, and rehydration kinetics were determined. Results showed that freeze-dried salmon cubes from each of the 3 Pacific salmon species can be produced with a moisture content of less that 10% and a(w) less 0.4 and freeze-drying time of 9 h. Processing yields ranged from 26% to 28.4%, depending on fish species. Shrinkage
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