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D Ansorena

Publications and source records attributed to D Ansorena.

8 recordsLinked to original sources
PubMed2001

Optimizing headspace temperature and time sampling for identification of volatile compounds in ground roasted Arabica coffee.

Equilibration time and temperature were the factors studied to choose the best conditions for analyzing volatiles in roasted ground Arabica coffee by a static headspace sampling extraction method. Three temperatures of equilibration were studied: 60, 80, and 90 degrees C. A larger quantity of volatile compounds was extracted at 90 degrees C than at 80 or 60 degrees C, although the same qualitative profile was found for each. The extraction of the volatile compounds was studied at seven different equilibration times: 30, 45, 60, 80, 100, 120, and 150 min. The best time of equilibration for headspace analysis of roasted ground Arabica coffee should be selected depending on the chemical class or compound studied. One hundred and twenty-two volatile compounds were identified, including 26 furans, 20 ketones, 20 pyrazines, 9 alcohols, 9 aldehydes, 8 esters, 6 pyrroles, 6 thiophenes, 4 sulfur compounds, 3 benzenic compounds, 2 phenolic compounds, 2 pyridines, 2 thiazoles, 1 oxazole, 1 lactone, 1 alkane, 1 alkene, and 1 acid.

Alcohols↗
PubMed2001

Postprandial de novo lipogenesis and metabolic changes induced by a high-carbohydrate, low-fat meal in lean and overweight men.

BACKGROUND: Adjustments of carbohydrate intake and oxidation occur in both normal-weight and overweight individuals. Nevertheless, the contribution of carbohydrates to the accumulation of fat through either reduction of fat oxidation or stimulation of fat synthesis in obesity remains poorly investigated. OBJECTIVE: The objective of this study was to assess the postprandial metabolic changes and the fractional hepatic de novo lipogenesis (DNL) induced by a high-carbohydrate, low-fat meal in lean and overweight young men. DESIGN: A high-carbohydrate, low-fat meal was administered to 6 lean and 7 overweight men after a 17.5-h fast. During the fasting and postprandial periods, energy expenditure (EE), macronutrient oxidation, diet-induced thermogenesis, and serum insulin, glucose, triacylglycerol, and fatty acids were measured. To determine DNL, [1-13C]sodium acetate was infused and the mass isotopomer distribution analysis method was applied. RESULTS: After intake of the high-carbohydrate meal, the overweight men had hyperinsulinemia and higher fatty acid and triacylglycerol concentrations than did the lean men. The overweight group showed a greater EE, whereas there was no significant difference in carbohydrate oxidation between the groups. Nevertheless, the overweight men had a marginally higher protein oxidation and a lower lipid oxidation than did the lean men. DNL was significantly higher before and after meal intake in the overweight men and was positively associated with fasting serum glucose and insulin concentrations. Furthermore, postprandial DNL was positively correlated with body fat mass, EE, and triacylglycerol. CONCLUSION: After a high-carbohydrate, low-fat meal, overweight men had a lower fat oxidation and a higher fractional hepatic fat synthesis than did lean men.

Adult↗
PubMed2001

Fatty acid modifications and cholesterol oxidation in pork loin during frying at different temperatures.

The effect of frying with sunflower oil for 4 min at different temperatures (160, 170, and 180 degrees C) on fatty acids and cholesterol of pork loin meat was studied. Total fat content increased from 5.6% in fresh loin to 7.3, 7.8, and 12.1% at 160, 170, and 180 degrees C, respectively. Interactions with culinary fat gave rise to a significant increase in unsaturated acids/saturated acids and polyunsaturated acids/saturated acids ratios, which could be considered an advantage from a nutritional point of view. Less than 1 ppm (microg/g of sample) of cholesterol oxidation products was detected in fresh loin, whereas fried loin pork contained between 8.58 and 10.89 ppm. 7-Ketocholesterol (5.99 to 8.47 ppm in fried samples) and 7beta-hydroxycholesterol (1.43 to 2.55 ppm in fried samples) were the main cholesterol oxidation products. Cholestanetriol was not detected in any sample, and small quantities of 25-hydroxycholesterol and 5,6alpha-epoxycholesterol were found in the fried sample.

Animals↗
PubMed2001

Analysis of fatty acid isomers in ruminant tissues by silver thin layer chromatography followed by gas chromatography.

A method for the analysis of trans fatty acids is described in this paper. Separation of trans isomers from the corresponding cis was based on the different facility with which the double bonds in the alkyl chains of both types of fatty acids form polar complexes with silver, and it was carried out by Thin Layer Chromatography (TLC), using silver nitrate impregnated plates. Further separation, identification and quantification of the individual C18:1 isomers, analysed as methyl esters, was carried out by Gas Chromatography (GC). The determination of the content of the isomer t11-C18:1 in ruminant tissues can contribute to try to elucidate the metabolic pathway formation of conjugated linoleic acid (CLA), shown as a fatty acid of beneficial health effects. Furthermore, the analysis of trans fatty acids in other dietary foods seems to be interesting due to their influence on the modification of the serum lipids profile and the role of this type of compounds in human health.

Animals↗
PubMed2001

Extractibility of the protein and peptide fraction for different types of dry fermented sausages in relation to GPC-analysis.

The use of GPC (gel filtration chromatography) for investigating the proteolysis during fermentation and ripening of dry fermented sausages (Northern and Mediterranean type) and the choice of a suitable extraction solvent for this technique was evaluated. Solvents in a wide range of acidity were used in this experiment (pH 0.5-13). A calculation of the percentage extracted nitrogencompounds for each solvent and a comparison of the GPC-profile for each extract select the HCl-dilutions with a pH 1 to 3 as the most suitable extraction solvent. Although very basic solvents extract most of the protein and peptide fraction, they lead to some degradation of the proteins and peptides and are not reliable. Clear differences between the GPC-profiles for both types of sausages were not observed.

Animals↗
PubMed2000

Influence of the simultaneous addition of the protease flavourzyme and the lipase novozym 677BG on dry fermented sausage compounds extracted by SDE and analyzed by GC-MS.

A dry fermented sausage (chorizo de Pamplona) was elaborated with the simultaneous addition of a lipase (Novozym 677BG) and a protease (Flavourzyme) and ripened during 21 days, in contrast to the control without enzymes and ripened during 35 days. Faster and more intense lipolytic and proteolytic activities were observed in the modified sausage, despite its shorter maturation time. At the end of the ripening, a determination of the profile of compounds extracted by simultaneous distillation-extraction with dichloromethane was carried out. The total amounts of extracted compounds (expressed in milligrams of dodecane per gram of dry matter) were 2.5 in the sausage with enzymes and 1.9 in the control. The chemical groups showing increments due to the use of enzymes were esters (103.5% increment) and acids (87% increment) in both cases due to the greater presence of long-chain fatty acid products. However, development of substances originated from further degradation process of amino acids and free fatty acids did not seem to have taken place.

Animals↗
PubMedDate not supplied

[Functional components in fish and algae oils].

An important area of the development of new functional foods is facussed on finding or applying food components which favour achieving a healthier lipid profile in the organism. The objective of this work was to carry out the characterisation of the lipid fraction of two oils, fish oil and algae oil, to evaluate their potential use as functional ingredients, in relation to the high molecular weight fatty acid content and the presence of sterols and other components of the unsaponificable fraction. Both oils showed a lipid fraction rich in high molecular weight polyunsaturated omega-3 fatty acids, containing a 33.75% in the fish oil and a 43.97% in the algae oil. Eicosapentaenoic acid was the major fatty acid in fish oil, whereas docosahexaenoic was the most abundant fatty acid in algae oil. The omega-6/omega-3 ratio was lower than 0.4 in both oils. In the unsaponificable fraction, algae oil had a Mold lower cholesterol content and a higher proportion of squalene than fish oil. The phytosterol content was significantly higher in the algae oil.

Eukaryota↗