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Cabezas D.M.,National University of La Plata | Madoery R.,National University of Cordoba | Diehl B.W.K.,Spectral Service GmbH Laboratorium fur Auftragsanalytik | Tomas M.C.,National University of La Plata
JAOCS, Journal of the American Oil Chemists' Society | Year: 2012

Lecithins are a mixture of acetone-insoluble phospholipids and other minor substances (triglycerides, carbohydrates, etc.). The most commonly processes used for lecithin modification are: fractionation by deoiling to separate oil from phospholipids, fractionation with solvents to produce fractions enriched in specific phospholipids, and introduction of enzymatic and chemical changes in phospholipid molecules. The aim of this work was to evaluate the emulsifying properties of different modified sunflower lecithins in oil-in-water (O/W) emulsions. In this study, five modified sunflower lecithins were assessed, which were obtained by deoiling (deoiled lecithin), fractionation with absolute ethanol (PC and PI enriched fractions), and enzymatic hydrolysis with phospholipase A 2 from pancreatic porcine and microbial sources (hydrolyzed lecithins). Modified lecithins were applied as an emulsifying agent in O/W emulsions (30:70 wt/wt), ranging 0.1-2.0% (wt/wt). Stability of different emulsions was evaluated through the evolution of backscattering profiles (%BS), particle size distribution, and mean particle diameters (D [3, 4], D [3, 2]). PC enriched fraction and both hydrolyzed lecithins presented the best emulsifying properties against the main destabilization processes (creaming and coalescence) for the analyzed emulsions. These modified lecithins represent a good alternative for the production of new bioactive agents. © AOCS 2011.

Ixtaina V.Y.,CONICET | Ixtaina V.Y.,National University of Central Buenos Aires | Martinez M.L.,CONICET | Spotorno V.,Instituto Nacional de Tecnologia Agropecuaria | And 5 more authors.
Journal of Food Composition and Analysis | Year: 2011

The oil yield, fatty acid composition and the physicochemical and quality characteristics of chia crude seed oils obtained by pressing and solvent extraction were determined. The extraction methods assayed influenced significantly the oil yield, obtaining about 30% more oil by solvent than by pressing. The main fatty acids ranked in the following order of abundance: α-linolenic acid (α Ln). > linoleic acid (L). > oleic acid (O). ≈ palmitic acid (P). > stearic acid (S) for both extraction systems. The n-3/. n-6 FA ratio of chia oils ranged from 3.18 to 4.18, being markedly higher than that reported for other vegetable oils. The main triacylglycerols were: αLnαLnαLn. > αLnαLnL. > αLnLL. > αLnαLnP. > αLnLO. ∼ αLnLP, which represent about 87-95% of the total content of these compounds. The quality and composition of some minor constituents of chia seed oils were influenced by the extraction process. Oils presented a moderate content of bioactive components, such as tocopherols, polyphenols, carotenoids and phospholipids; the high unsaturation level determined their low oxidative stability. © 2010 Elsevier Inc.

Guiotto E.N.,National University of La Plata | Cabezas D.M.,National University of La Plata | Diehl B.W.K.,Spectral Service GmbH Laboratorium fur Auftragsanalytik | Tomas M.C.,National University of La Plata
European Journal of Lipid Science and Technology | Year: 2013

Fractions enriched in specific phospholipids are desirable for different industrial purposes because of their characteristic physicochemical and functional properties. We studied the fractionation process of sunflower lecithin using different absolute-ethanol/water ratios and pHs and then evaluated the emulsifying properties of phosphatidyl-choline-(PC-) enriched fractions in oil/water 30:70 v/v emulsions. We observed a high recovery of PC and a low content of phosphatidyl inositol (PI) in all the PC-enriched fractions thus obtained along with the highest yields of this phospholipid after extraction with an absolute-ethanol/water mixture of 96:4 v/v. The use of different pH values for the different solvent extraction media did not markedly modify the yield of the enriched fractions. The extraction coefficients for PC and phosphatidyl ethanolamine (PE) evidenced an increase in both these phospholipids in the PC-enriched fractions upon extraction with the higher concentration of absolute ethanol. Emulsions containing the PC-enriched fractions obtained with the absolute-ethanol/water mixture of 96:4 v/v exhibited the highest stability at pH 7.5 because of the high PC/PE ratio compared to that of the PC-enriched fractions extracted with the absolute-ethanol/water mixture of 90:10 v/v. A high emulsifier concentration resulted in a low mean D [4,3] diameter of the particles and a high stability. Practical applications: Sunflower lecithin is a promising alternative to soybean lecithin because it is considered the product of a non-genetically modified organism (non-GMO). Experimentation on lecithin modification under industrial conditions with adequate techniques of analysis may be useful for evaluating the potential applications of these sunflower by-products to the production of new emulsifiers. Thus, an analysis of the influence of different fractionation parameters, such as the pH of the solvent extraction, on the composition and emulsifying properties of the resulting PC-enriched fractions may provide useful information for the food industry. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cabezas D.M.,National University of La Plata | Diehl B.W.K.,Spectral Service GmbH Laboratorium fur Auftragsanalytik | Tomas M.C.,National University of La Plata
European Journal of Lipid Science and Technology | Year: 2013

The enzymes used in degumming, called phospholipases, specifically act on phospholipids without degrading the oil itself. Degumming using a phospholipase C enzyme allows to meet all market specifications while it increases the oil yield. The aim of this study was to evaluate antioxidant and emulsifier properties of the recovered gum (RG) obtained by enzymatic oil degumming process of crude soybean oil subjected to modifications as deoiling (RG deoiled) or ethanol fractionation (RG soluble and insoluble). RG soluble allowed obtaining more stable oil-in-water emulsions (30:70 w/w) in comparison with those by-products assayed at different concentrations (0.1-1.0%). Also, deoiled soybean lecithin (DSL) and RG deoiled had a similar behavior in relation to the kinetic destabilization (% backscattering profiles), despite the different degumming processes used to obtain these samples. The study on induction times (Metrohm Rancimat) showed a significant antioxidant effect (p<0.05) against a refined sunflower oil associated with all the by-products analyzed. However, RG soluble and DSL showed a strong effect on the oil stability at high concentrations (1000-2000ppm). These results showed that the deoiled recovered gum and its derivates obtained by ethanol fractionation are a potential alternative for industrial application as additive. Practical applications: The economic benefits of enzymatic degumming process have also been quantified by several oilseed processors. This process allows obtaining a by-product with a high concentration of different phospholipids. This study intends to increase the commercial value of this recovered gum contributing to the food industry with useful information about their functional properties. © 2013.

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