Showing papers on "Fish oil published in 1977"

Effect of polyunsaturated fatty acids of the α‐linolenic series on the development of rat testicles

Abstract: The effect of 22∶6ω3 acid provided by dietary fish oil on the development of germinal tissue of rat testes, fatty acid composition of lipids, and linoleic or α-linolenic acid Δ6 desaturation capacity was investigated. Results were compared to those obtained in animals fed methyl palmitate and sunflower seed oil (linoleate). At 7 and 9 weeks of age, development of germinal tissue of animals fed fish oil was normal. The fatty acid composition showed a decrease in 22∶5ω6 acid content and an increase in 22∶6ω3 acid in triacylglycerol, phosphatidylcholine, and phosphatidylethanolamine. The fatty acid Δ6 desaturation capacity of testicules microsomes was increased. It is suggested that 22∶6ω3 acid may functionally replace 22∶5ω6 acid in germinal tissue.

Hydrogenated marine fat, its influence on rat tissue lipids, compared to fish oil, rape seed oil and lard

Abstract: A feeding experiment on rats has been performed, comparing fish oil and partially hydrogenated fish oil (HMF) with rape seed oil and lard. After a two week preliminary period during rvhich the percentageof lard in the diet was increased from 7% to 20%, four groups of rats were fed diets containing 20% of the four fats for 12 weeks. Growth was controlled, and samples of liver, heart, thigh muscle and brown adipose tissue taken after 1 , 2 , 6 and 12 weeks. Lipids of these tissues were separated into neutral and polar fractions, and the fatty acids prepared and analyzed on GLC. Results are given and discussed. The following conclusions are

Extraction Rate of Fish Oil from Tuna Flesh

Abstract: Extraction rates of fish oil in tuna flesh with dichloroethane, isopropyl alcohol, ethyl alcohol, methlethylketone, hydroxyethylmethylether and their respective azeotropes with water were studied. The apparent diffusivities were all in the order of 1O-7cm2/sec except hydroxyethylmethylether, which gave a value of 10-6 cm2/sec. The theoretical and practical meanings are discussed. Introduction The fish meal process now widely used consists of cooking, compression in a hydraulic press to extract part of the oil, centrifugation drying in rotary drum dryers, grinding and packing. The resultant product contains about 65% protein, 5-8% oil, 15% ash and the rest is moisture. The highly unsaturated fish oil is partly oxidized in the drying and some antioxidant added to prevent further peroxide formation. However, the fish can still oxidize, to give a strong, disagreeable flavor to the meal so it is not recommended for final feeding of chickens or pigs, as it would impart flavor to the meat. An alternative process which costs somewhat more but completely eliminates the fish flavor, uses solvent extraction instead of compression, and, as expected, the product of the process is better and could be suitable for human foodl ). We have investigated the extraction rates of fish oil from tuna flesh with dichloroethane (DEO) and determined the extraction rate, and dependencies on fiber direction and temperature. We observed that the R-t curve has a break point, and speculated on the mechanism2) 3) 4). Further studies are in progress. Realstic order-of-magnitude extraction rates with various solvents and different species are necessary for practical plant design. We used the solvents, DOE, isopropyl alcohol (IPA) , ethyl alcohol (EA), methylethylketone (MEK), hydroxyethylmethylether (HEME), their respective azeotropes with water. All the solvents mentioned except HEME have boiling points between 73° and 83°0, and were chosen for the ease of solvent removal and the prevention of evaporation loss, which counteract each other. Theoretical Fish flesh is not a single chemical entity and its properties, which include diffusivity, depend upon fish, part of the body, sex, age, season of capture, time * Lahoratory of Ohemical Engineering, Fueulty of Fisheries, Hokkaido University (;jt1fif**~£~${t.~I~~)