Search results for "saturated fat"
showing 10 items of 333 documents
Metabolic effects of omega-3 fatty acids.
2001
Some metabolic effects of dietary marine oils, or of dietary eicosapentaenoic or docosahexaenoic acid are reviewed. It is pointed out that docosahexaenoic acid appears more effective as regards induction of peroxisomal beta-oxidation. Similarly, docosahexaenoic appears more powerful in terms of suppression of hepatic delta9-desaturase activity and mRNA-levels. The potential inhibitory effect of polyunsaturated fatty acids, particularly docosahexaenoic acid, on mitochondrial beta-oxidation is discussed. Experiments with rats suggesting that the hypolipidaemic response of eicosapentaenoic acid is more marked when the fatty acid was given to fed rats, as compared to fasted rats, are discussed.
Effect of natural antioxidants and modified atmosphere packaging in preventing lipid oxidation and increasing the shelf-life of common dolphinfish (C…
2015
We investigated the effects of natural antioxidants and modified atmosphere packaging (MAP) on the quality and shelf-life of Coryphaena hippurus (common dolphinfish) fillets. Fillets of the control group (CO) were simply placed on trays and not sealed. Fillets of the second group (MAP) were preserved in modified atmosphere (45% CO2, 50% N2, 5% O2), and fillets of the third group (MAP-AOX) were preserved by combining natural antioxidants from halophytes with modified atmosphere. All samples were stored in a refrigerator at 1 ± 0.5 C for 18 days. Analyses were conducted at T0 and after 3, 6, 12, 15 and 18 days of storage. According to sensory tests and colour analyses, the fillets in the MAP …
Method for evaluating the bioconversion of radioactive polyunsaturated fatty acids by use of reversed-phase liquid chromatography
1988
Abstract Reversed-phase high-performance liquid chromatography on a thermostatted octadecylsilyl column was used to separate mixtures of labelled polyunsaturated fatty acids (as their methyl esters) formed by successive desaturations and elongations of labelled linoleic (18:2 n - 6) or linolenic (18:3 n -3) acid by rat liver microsomes. Acetonitrile-water mixtures were used for elution of the esters. Unsaturated and saturated esters were detected by their refractive indices. The order of elution of fatty acid methyl esters in complex mixtures varies as a function of the chain length and unsaturation, analysis temperature, water concentration and solvent flow-rate. The peak areas vary as a f…
Determination of unsaturation grade and trans isomers generated during thermal oxidation of edible oils and fats by FTIR
1999
Abstract The oxidative deterioration of culinary oils and fats during episodes of heating associated with normal usage (80°C–300°C, 20–40 min) was monitored by FTIR spectroscopy. The thermal oxidation of polyunsaturated fatty acids during heating was studied by the determination of unsaturation percentage and trans isomers at various temperatures and heating times. Oils frequently used in food frying such as olive oil, sunflower oil, corn oil and seeds oil (sunflower, safflower and canola seed), and lard were studied. The Absorbance Correction Method is proposed to correct the spectral interference and allows the analytic use of signal which would not be initially valid for quantitative ana…
Analytical evaluation of polyunsaturated fatty acids degradation during thermal oxidation of edible oils by Fourier transform infrared spectroscopy
1998
The oxidative deterioration of polyunsaturated fatty acids (PUFAs) in culinary oils and fats during episodes of heating associated with normal usage (80-300 degrees C, 20-40 min) has been monitored by Fourier transform infrared spectroscopy (FTIR). The thermal oxidation of PUFAs is a free radical chain reaction, in which hydroperoxides are generally recognized as the primary major products. Hydroperoxides of PUFAs are easily decomposed into a very complex mixture of secondary products with the decrease in unsaturation. The oxidative advance of PUFAs during heating was studied by the determination of unsaturation percentage at different temperatures and heating times. Oils frequently used in…
Lipid content of Saccharomyces cerevisiae strains with different degrees of ethanol tolerance
1992
We analysed the fatty acid and sterol compositions of various Saccharomyces cerevisiae strains with ethanol tolerance varying from 4% to 12% (v/v) ethanol and at different concentrations of ethanol. The results we obtained agree with the existence of a relationship between membrane fluidity and ethanol tolerance but they do not support a direct role of unsaturated fatty acids in this tolerance. On the other hand, they support the importance of ergosterol in this phenomenon.
Fatty Acid Composition in the Lipids of some Marine Chiorococcales and Eustigmatales
1989
Abstract The fatty acid composition in the lipids of six coccoid microalgae species (≈ 2 μm in diameter) was investigated. In addition to analyses of ultrastructure and pigment content, lipid composition is shown to be a chemotaxonomic tool in the classification of algae. The four species of Chiorococcales (Chlorophyceae) - the marine species as well as the fresh water species, both kept in artificial seawater - contain a fatty acid composition resembling that of Chlorella spp. and of green leaves of higher plants. The fatty acid pattern is characterized as lacking in C20 acids but containing large amounts of C 16 and C 18 polyunsaturated fatty acids, hexadecatrienic acid (16 :3) and a-lino…
Ruminant fat volatiles as affected by diet. A review.
2006
Volatile compounds in meat have been widely studied for their favourable or undesirable effects on meat flavour, or for their potential use in tracing the animal feeding system. To date, the chemical mechanisms causing the appearance of volatile compounds in meat have been largely understood. Several variables are involved in the accumulation of volatiles in animal tissues and among them animal diet plays a key role. The purpose of the present review is to highlight the effects of different dietary regimes (concentrate, green grass and fat-enriched diets) on the appearance of fat volatile compounds in ruminant meat. Grain-based diets induce greater accumulations in meat of branched-chain fa…
EFFECTS OF CYCLOPROPENOID FATTY ACIDS (BAOBAB SEED OIL) ON THE FATTY ACID PROFILE OF LIPIDS FROM DIFFERENT TISSUES IN THE RAT
1996
Rats were fed for 8 weeks a diet containing either Baobab seed oil (FBO) rich in cyclopropenoid fatty acids (CPFA) or heated oil (HBO) devoid of CPFA. In FBO rats, compared to controls (CO), the monounsaturated fatty acid content of adipose tissue lipids, liver triacylglycerols, liver and adrenal cholesteryl esters and liver, kidney, adrenal phospholipids were highly decreased to the benefit of saturated fatty acid content. In cholesteryl esters and phospholipids, the arachidonic acid (20:4 n-6) content was markedly decreased, especially in adrenals. In adrenal cholesteryl esters, adrenic acid (22:4 n-6) content was decreased more than its precursor. The effects of HBO on the tissue lipid f…
Effect of ewe feeding system (grass v. concentrate) on intramuscular fatty acids of lambs raised exclusively on maternal milk
2005
AbstractTwenty pregnant Comisana ewes were divided into two groups of 10. One group was allowed to graze a vetch pasture (grass). The second group of animals was housed collectively in a pen and was given hay and concentrates (concentrate). After lambing, all the ewes were allowed to stay with the respective lambs between 18:00 h and 07:00 h of the following day in two different pens. Therefore all the lambs were raised exclusively on maternal milk. The lambs were slaughtered at 38 days of age. Milk and lamb meat (longissimus dorsi muscle) fatty acids were analysed. Ewes on grass produced milk with a lower (P< 0·001) proportion of saturated fatty acids and with a higher proportion of bot…