This work was undertaken to study the impact of the source of n-3 FA on their incorporation in serum, on blood lipid composition, and on cellular activation. A clinical trial comprising 71 volunteers, divided into five groups, was performed. Three groups were given 400 g smoked salmon (n = 14), cooked salmon (n = 15), or cooked cod (n = 13) per week for 8 wk. A fourth group was given 15 mL/d of cod liver oil (CLO) (n = 15), and a fifth group served as control (n = 14) without supplementation. The serum content of EPA and DHA before and after intervention revealed a higher rise in EPA and DHA in the cooked salmon group (129% rise in EPA and 45% rise in DHA) as compared with CLO (106 and 25%, respectively) despite an intake of EPA and DHA in the CLO group of 3.0 g/d compared with 1.2 g/d in the cooked salmon group. No significant changes were observed in blood lipids, fibrinogen, fibrinolysis, or lipopolysaccharide (LPS)-induced tissue factor (TF) activity, tumor necrosis factor-alpha (TNFalpha), interleukin-8 (IL-8), leukotriene B4 (LTB4), and thromboxane B2 (TxB2) in whole blood. EPA and DHA were negatively correlated with LPS-induced TNFalpha, IL-8, LTB4, TxB2, and TF in whole blood. In conclusion, fish consumption is more effective in increasing serum EPA and DHA than supplementing the diet with fish oil. Since the n-3 FA are predominantly in TAG in fish as well as CLO, it is suggested that the larger uptake from fish than CLO is due to differences in physiochemical structure of the lipids.

The influence of various dietary marine oils and olive oil on fatty acid composition of serum and platelets and effects on platelets and serum lipids were investigated as part of an extensive study of the effects of these oils on parameters associated with cardiovascular/thrombotic diseases. Healthy volunteers (266) consumed 15 mL/d of cod liver oil (CLO); whale blubber oil (refined or unrefined); mixtures of seal blubber oil and CLO; or olive oil/CLO for 12 wk. In the CLO, seal oil/CLO, and whale oil groups, serum levels of eicosapentaenoic acid (EPA) were increased. In platelets, EPA was increased in the CLO, seal/CLO, and olive oil/CLO groups. The localization of n-3 polyunsaturated fatty acids in the triacylglycerols did not seem to influence their absorption. Intake of oleic acid is poorly reflected in serum and platelets. No significant differences in triacylglycerols (TG), total cholesterol, or high density lipoprotein cholesterol were observed, even though TG were reduced in the CLO, CLO/seal oil, and whale oil groups. Mean platelet volume increased significantly in both whale oil groups and the CLO/olive oil group. Platelet count was significantly reduced in the refined whale oil group only. Lipopolysaccharide-stimulated blood tended to generate less thromboxane B2 in CLO, CLO/seal, and CLO/olive groups. The whale oils tended to reduce in vivo release of beta-thromboglobulin. In conclusion, intake of various marine oils causes changes in platelet membranes that are favorably antithrombotic. The combination of CLO and olive oil may produce better effects than these oils given separately. The changes in platelet function are directly associated with alterations of fatty acid composition in platelet membranes.

A study was performed to explore the effects of supplemental intake of various marine oils known to be part of the Eskimo diet. Healthy men and women (134) were randomly selected to consume 15 mL/d of oil from blubber of seal, cod liver, seal/cod liver, blubber of Minke whale, or no oil for ten weeks. Total cholesterol was unchanged in the oil groups, whereas high density lipoprotein cholesterol increased 7% in the seal/cod liver oil (CLO) group (P < 0.05) and 11% in the whale oil group (P < 0.005). Triacylglycerol was significantly reduced in the CLO group only. The concentration of prothrombin fragment 1 + 2 was reduced 25% (P < 0.05) after whale oil supplementation. No change in fibrinogen or factor VIIc was detected. Tumor necrosis factor generation in lipopolysaccharide (LPS)-stimulated blood was 30% reduced after whale oil (P < 0.05), but was unaffected by intake of seal or CLO. The LPS-induced tissue factor activity in monocytes was reduced to a significant degree only in the seal/CLO group (34%) and whale oil group (35%) (P < 0.05). The most dramatic change in thromboxane B2 in LPS-stimulated blood was seen after whale oil intake with 44% reduction (P < 0.01). Supplementation of a regular diet with a combination of seal oil and CLO and especially with whale oil seems to have beneficial effects on several products thought to be associated with cardiovascular and thrombotic diseases.

Marine triglyceride oils (cod liver oil and oils from blubber of harp seal and minke whale)were reacted with glycerol using lipase as a catalyst at low temperature. A solventfree batch system with magnetic stirring was used. Solidification of the reaction mixture occurred, and a mixture of mono-, di-, and triglycerides was obtained in all cases. The recovered glyceride mixtures were solid at room temperature. The yield of monoglyceride (MG) and the fatty acid profile of the MG fractions were dependent on oil and the type of lipase used as a catalyst. Of the commercially-available lipases investigated, [ipase AK from Pseudomonas sp. synthesized the highest yield of MG (42-53%) at 5°C. These MG fractions were low in saturated fatty acids (4-11%) and high in long-chain monounsaturated fatty acids (52-69%). The concentration of n-3 polyunsaturated fatty acids was 12-20%.JAOCS 72, 1339-1344 (1995).

Saithe, a lean gadoid fish, was processed and stored at −10C, −20C and −30C as normal skinless fillets and as deep‐skinned fillets. Properties related to lipid oxidation in the dark and light muscle tissues and in the two types of fillets were investigated after 6 to 9 months of storage. The lipid content and fatty acid profiles indicated the presence of relatively large amounts of triacylglycerols in the dark muscle. Prolonged storage at −10C and −20C resulted in a decrease in the content of n‐3 polyunsaturated fatty acids (n‐3 PUFA) in the dark muscle tissue. At the highest temperature, a reduction in n‐3 PUFA is also indicated in the light muscle. Lipid oxidation as measured by 2‐thiobarbituric acid reactive substances (TBARS) and reduction in α‐tocopherol, was most pronounced in the dark muscle. Evaluation of fillets by sensory analyses and TBARS values demostrated that industrial deep‐skinning improves cold storage stability of saithe fillets.