Fatty acid composition of hydrogenated vegetable oils

1947 ◽  
Vol 24 (11) ◽  
pp. 382-387 ◽  
Author(s):  
G. S. Fisher ◽  
R. T. O'Connor ◽  
F. G. Dollear
1995 ◽  
Vol 78 (3) ◽  
pp. 783-801 ◽  
Author(s):  
Wakisundera M N Ratnayake

Abstract An infrared spectrophotometric (IR) method for the determination of total trans unsaturated fatty acid (trans) content and a combined gas–liquid chromatographic/infrared spectrophotometric (GC/IR) method for determination of fatty acid composition of partially hydrogenated vegetable oils (PHVO) were studied collaboratively in 12 laboratories using 7 PHVO samples, including 1 pair of blind duplicates. The test samples were methylated and analyzed for total trans content by IR and for fatty acid composition by GC/IR using a capillary column coated with SP-2560 or another suitable cyanoalkylsiloxane stationary phase. From the measured IR absorption, the isolated trans content was calculated using a calibration curve of absorption versus trans content developed with 2-component calibration standard mixtures of methyl elaidate and oleate. The GC provided the levels of mono-trans-octadecadienoates (18:2t), di-trans-octadecadienoates (18:2tt) and mono-trans-octadecatrienoates (18:3t). The trans-octadecenoate (18:1t) content was calculated with the formula: 18:1t = IR trans−0.84 × (18:2t + 18:3t − 1.74 × 18:2tt. The cisoctadecenoate (18:1c) content was obtained as the difference between total octadecenoates (18:1) and 18:1t. Reproducibility relative standard deviations (RSDR) for 15 to 35% trans content determined by IR were in the range of 8.8–11.7%, whereas RSDR for the test sample with 5% trans content was 34.6%. RSDR values for 18:1t by the GC/IR followed the same pattern as that of IR trans values: 36.4% for the test sample with 4.9% 18:1t versus 7.8–12.5% for test samples with 14.9 to 32.6% 18:1t. The content of 18:1 c in the test samples varied from 24.7 to 34.5% and their RSDR values ranged from 3.8 to 10.5%. The mean values for 18:1t and 18:1c compared favorably with the absolute levels determined by a silver nitrate-thin layer chromatography/GC procedure. The IR and GC/IR methods are recommended for determination of trans content and fatty acid composition, respectively, of partially hydrogenated fats derived from vegetable oils, terrestrial animal fats or such oils and fats isolated from food products containing >5% trans fatty acids. For samples containing ≤5% trans fatty acids, a direct GC method (American Oil Chemists' Society Official Method Ce 1c-89) is available for determination of both trans content and fatty acid composition, because at lower trans levels, overlap of 18:1 cis and trans isomers on GC with very polar capillary columns is negligible. The IR method for determination of isolated trans unsaturated fatty acid content in partially hydrogenated fats and the capillary GC/IR method for determination of total cis- and trans-octadecenoic isomers and general fatty acid composition in hydrogenated vegetable oils and animal fats have been adopted first action by AOAC INTERNATIONAL.


2007 ◽  
Vol 90 (5) ◽  
pp. 1465-1469 ◽  
Author(s):  
Brent D Flickinger

Abstract The role of dietary fat in health and wellness continues to evolve. In today's environment, trans fatty acids and obesity are issues that are impacted by dietary fat. In response to new information in these areas, changes in the amount and composition of edible fats and oils have occurred and are occurring. These compositional changes include variation in fatty acid composition and innovation in fat structure. Soybean, canola, and sunflower are examples of oilseeds with varied fatty acid composition, including mid-oleic, high-oleic, and low-linolenic traits. These trait-enhanced oils are aimed to displace partially hydrogenated vegetable oils primarily in frying applications. Examples of oils with innovation in fat structure include enzyme interesterified (EIE) fats and oils and diacylglycerol oil. EIE fats are a commercial edible fat innovation, where a lipase is used to modify the fat structure of a blend of hard fat and liquid oil. EIE fats are aimed to displace partially hydrogenated vegetable oils in baking and spread applications. Diacylglycerol and medium-chain triglyceride (MCT)-based oils are commercial edible oil innovations. Diacylglycerol and MCT-based oils are aimed for individuals looking to store less of these fats as body fat when they are used in place of traditional cooking and salad oils.


Author(s):  
В.И. МАРТОВЩУК ◽  
С.А. КАЛМАНОВИЧ ◽  
А.А. ЛОБАНОВ ◽  
Е.В. МАРТОВЩУК

Исследовано влияние механохимической активации на гидратируемость фосфолипидов растительных масел. Для эксперимента использовали механохимический активатор, обеспечивающий высокие локальные давления, сдвиговые деформации и кавитационный эффект, при следующих параметрах работы: давление на контактирующих поверхностях 70 МПа, частота 180 Гц, скорость сдвига 10200 с–1, размер капли эмульсии 1–2 мкм. Обработку образцов подсолнечного масла осуществляли в течение от 0 до 80 с при температурах 50, 60 и 70°С. Активность фосфолипидов оценивали по величине их адсорбции на границе с полярной поверхностью (водой) в оптимальном температурном режиме при обработке в механохимическом активаторе и без нее. Установлено, что механохимическая активация способствует снижению энергии активации с 6,4 до 4,7 кДж/моль за счет химических и структурных изменений фосфолипидов. В жирнокислотном составе фосфолипидов на 10–12% увеличилось содержание олеиновой кислоты при соответствующем уменьшении линолевой; в фосфатидилэтаноламинах и фосфатидилсеринах отмечено увеличение до 3% содержания пальмитиновой кислоты и незначительно – стеариновой кислоты. Эти изменения жирнокислотного состава и физических свойств фосфолипидов способствуют повышению их гидратируемости и уменьшению доли полиненасыщенных жирных кислот, что должно обеспечить стабильность обработанных в механохимическом активаторе масел к окислению при хранении. The effect of mechanochemical activation on the hydration of phospholipids of vegetable oils has been studied. A mechanochemical activator providing high local pressures, shear deformations and cavitation effect was used for the experiment with the following operating parameters: pressure on the contact surfaces of 70 MPa, frequency of 180 Hz, shear rate of 10200 s–1, the size of the emulsion drop of 1–2 microns. Processing of sunflower oil samples was carried out during 0 to 80 s at temperatures of 50, 60 and 70°C. The activity of phospholipids was estimated by the amount of their adsorption at the border with the polar surface (water) in the optimal temperature mode when processed in a mechanochemical activator and without it. It was found that mechanochemical activation contributes to a decrease in the activation energy from 6,4 to 4,7 kJ/mol due to chemical and structural changes in phospholipids. In the fatty acid composition of phospholipids, the content of oleic acid increased by 10–12% with a corresponding decrease in linoleic acid; in phosphatidylethanolamines and phosphatidylserines, the increase in the content of palmitic acid was noted to 3%, and stearic acid – slightly. These changes in the fatty acid composition and physical properties of phospholipids contribute to increasing their hydration and reducing the proportion of polyunsaturated fatty acids, which should ensure the stability of the oils processed in the mechanochemical activator to oxidation during storage.


2021 ◽  
pp. 56-59
Author(s):  
Лев Арсенович Оганесянц ◽  
Александр Львович Панасюк ◽  
Елена Ивановна Кузьмина ◽  
Дмитрий Александрович Свиридов ◽  
Михаил Юрьевич Ганин

Продукты масложировой промышленности играют важную роль в формировании рациона питания человека. При этом особое внимание отводится растительным маслам ввиду их высокой физиологической ценности. На сегодняшний день достаточно остро стоит вопрос о способах их идентификации. В связи с тем, что стоимость растительного масла в значительной степени обуславливается выбором сырья, наиболее распространенным видом фальсификации является внесение недобросовестными производителями в готовую продукцию более дешевых видов масел. Приведен анализ современных способов идентификации растительных масел из различного сырья. До настоящего времени метод газожидкостной хроматографии являлся основным при выявлении примесей посторонних жиров в продукции по ее жирнокислотному составу. Также для выявления фальсификатов могут быть использованы такие инструментальные методы, как ЯМР-спектроскопия, ИК-спектроскопия, а также метод изотопной масс-спектрометрии, который является наиболее перспективным. Особый научный интерес представляет идентификация растительных масел по их географическому месту происхождения. Основываясь на анализе литературы, показано, что наибольшее распространение при установлении региональной принадлежности масел получили исследования, направленные на изучение изотопных характеристик углерода (13С/12С), кислорода (18O/16O) и водорода (2H/1H) элементов, входящих в состав продукта, а также его жирнокислотного состава. Описаны преимущества комплексного подхода исследований, включающего в себя создание массива данных, состоящего из значений различных показателей, и его глубокий анализ с использованием статистических методов анализа. Математическая модель может быть усилена данными элементного профиля масла, изотопных характеристик отдельно взятых жирных кислот или содержанием фенольных соединений. Products of the fat and oil industry play an important role in shaping human diet. At the same time, special attention is paid to vegetable oils in view of their high physiological value. Today, the question of how to identify them is quite acute. Due to the fact that the cost of vegetable oil is largely determined by the choice of raw materials, the most common falsification type is the introduction of cheaper oils types into finished products by unscrupulous manufacturers. The authors provide an analysis of modern methods for identifying vegetable oils from various raw materials. It has been shown that the gas-liquid chromatography method is the main one in identifying products by their fatty acid composition and makes it possible to establish the presence of foreign fats impurities. Also, methods of isotope mass spectrometry, NMR spectroscopy, IR spectroscopy and electrophysical methods of analysis can be used to detect counterfeits. Of particular scientific interest is the vegetable oils identification by their geographical place of origin, which is very important for some countries of the European Union. Based on the analysis of literature, it has been shown that the most widespread in the regional oils affiliation establishing are researches aimed at researching the isotopic characteristics of carbon (13C/12C), oxygen (18O/16O) and hydrogen (2H/1H) of the elements that make up the product, and also its fatty acid composition. The advantages of an integrated research approach are described, including the creation of a data array consisting of the values of various indicators and its in-depth analysis using statistical analysis methods. The mathematical model can be strengthened by data on the elemental profile of the oil, isotopic characteristics of individual fatty acids, or the content of phenolic compounds.


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