Analysis of glycolipids in vegetable lecithin with HPLC-ELSD

Vegetable lecithins play an important role in the microstructural and macroscopic properties of food and cosmetic products. They are widely used as a natural emulsifier. As lecithin is a by-product of the vegetable oil refining industry, its composition is quite variable and rather complex. Therefore, a more complete view on the chemical composition of lecithin would assist in elucidating its functionality. This study focused on the separation and quantification of several glycolipid classes in lecithin, namely (1) digalactosyldiacylglycerol (DGDG) and monogalactosyldiacylglycerol (MGDG), (2) steryl glucosides, (3) esterified steryl glucosides and (4) cerebrosides, using HPLC-ELSD. MGDG was not detected in soy lecithin

Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization.

The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD

Balancing functional and nutritional quality of oils and fats: Current requirements and future trends

Oils and fats play an important role in the structure, aroma and stability of a wide variety of food products, as well as in their nutritional properties. For Puratos, a producer of ingredients for bakery, patisserie and chocolate sector, functionality and taste are of utmost importance, but the company also wants to contribute to the balanced diet of consumers. Vegetable oils and fats are used in margarines and releasing agents, vegetable creams, compound chocolate, fillings and emulsifiers. Each application requires an oil or fat with specific physicochemical properties in order to ensure the optimal structure, stability and taste of the end product. Traditionally, (partially) hydrogenated vegetable oils deliver important functional characteristics concerning crystallization behaviour, directly linked with the workability, melting properties, stability and mouth feel of the food product. However, due to negative nutritional implications, trans fats are to be replaced by healthier alternatives, preferably not by saturated fats. Consumers – and in some regions, legal instances – demand transfree or hydro-free products while not compromising on taste. Alternative fats and oils will be discussed concerning their functional and nutritional properties

Characterisation of the physicochemical properties of two species of dragon fruit seed oil (Hylocereus undatus and Hylocereus polyrhizus)

Oil was extracted from the seed of white-flesh (Hylocereus undatus; WFSO) and red-flesh (Hylocereus polyrhizus; RFSO) dragon fruits using a cold extraction process with petroleum ether. The delta-, gamma-, and alpha-tocopherol content, fatty acid and triacylglycerols composition, thermal and rheological properties of the extracted dragon fruit seed oils were analysed. The results showed that the dragon fruit seeds contained a high amount of oil up to 34.13%. The principal tocopherol in WFSO and RFSO was alpha-tocopherol. The total tocopherols content of RFSO was 1.6 times higher than that of WFSO. The three main fatty acids in these oils were palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2). The seed oil is interesting from a nutritional point of view: the essential fatty acid content of WFSO and RFSO counts up to 55.64% and 45.37% respectively. The thermal curves for WFSO and RFSO consisted of five endothermic peaks and two crystallisation curves with a broader temperature range. The apparent viscosity of WFSO and RFSO was similar (14.24-14.32 mPa.s). Thus the dragon fruit seed oils can be considered as a new source of tocopherols and essential fatty acids

Characterisation of the physicochemical properties of two species of dragon fruit seed oil (Hylocereus undatus and Hylocereus polyrhizus)

Oil was extracted from the seed of white-flesh (Hylocereus undatus; WFSO) and red-flesh (Hylocereus polyrhizus; RFSO) dragon fruits using a cold extraction process with petroleum ether. The delta-, gamma-, and alpha-tocopherol content, fatty acid and triacylglycerol composition, thermal and rheological properties of the extracted dragon fruit seed oils were analysed. The results showed that the dragon fruit seeds contained a high amount of oil up to 34.13%. The principal tocopherol in WFSO and RFSO was alpha-tocopherol. The total tocopherols content of RFSO was 1.6 times higher than that of WFSO. The three main fatty acids in these oils were palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2). The seed oil is interesting from a nutritional point of view: the essential fatty acid content of WFSO and RFSO counts up to 55.64% and 45.37% respectively. The main triacylglycerol in WFSO and RFSO was LLL, LLO, PLL, LOO and PLO. The thermal curves for WFSO and RFSO consisted of two main endothermic peaks with a broader temperature range around these peaks of -49.58 and 3.41 °C. The apparent viscosity of WFSO and RFSO was similar (14.24-14.32 mPa.s). Thus the dragon fruit seed oils can be considered as a new source of tocopherols and essential fatty acids

Influence of refining of vegetable oils on minor components

Refining of crude vegetable oils involving degumming, bleaching and deodorization has a high influence on the content of functional minor components. In this study, the difference of chemical versus physical refining will be studied. Especially the reduction of the tocopherol content in refined oil is mainly due to oxidation of the tocopherol. Also the content of sterols in free and esterified form is changing during the various refining procedures. An alternative two-step deodorization is described