Comparative properties of Amazonian oils obtained by different extraction methods

Pequi (Caryocar brasiliense Camb.), baba?u (Orbignya phalerata Mart.), buriti (Mauritia flexuosa), and passion fruit (Passiflora edulis) oils were studied to determine their antibacterial, antioxidant and cytotoxic activities, as well as their total phenol and carotenoid contents. The fatty acid contents were determined by GC-MS. The three types of passion fruit oils studied were refined, cold pressed or extracted from seeds in a Soxhlet apparatus. The oils thus obtained showed differences in antioxidant activity and carotenoid content, but were similar in regard to total phenols. Buriti and pequi had the highest carotenoid contents, while refined and cold pressed passion fruit oil displayed the highest antioxidant activity. Pequi oil was the only oil to display antibacterial and cytotoxic activity.     

Comparative study of the oxidative and thermal stability of vegetable oils to be used as lubricant bases

Demand for lubricating oils is increasing in the growing Brazilian economy. The use of vegetable bases in exchange of minerals can bring socio-economic and environmental benefits for Brazil. The purpose of this study is to compare the thermal and oxidative stability of vegetable oils related to the bases commonly used as lubricants. In this study, thermogravimetric analysis of castor oil, cotton oil, macauba’s almond oil, passion oil, paraffinic mineral oil, naphthenic oil (NH-140) and synthetic oil (Etro) was performed in inert and oxidative atmosphere to study the thermal and oxidative degradation of the vegetable oils related to the most common lubricants’ oils base. These oils’ oxidation stability were determined by standard procedures (ISO 6886). The use of mineral oil’s additives in these vegetable oils was tested to verify the viability of these additives to improve the oxidative stability of the vegetable oils. The castor oil and the cotton oil presented results of thermal analysis similar to the mineral and synthetic bases values. The castor oil was the only vegetable oil that showed a great oxidative stability. All other vegetable oils had their oxidative stability significantly increased by the additives.     

痕量动物油和植物油的区分检验研究

采用碱催化甲酯化的前处理方法,应用气相色谱-质谱联用技术对动物油和植物油的区分检验进行了研究。实验检出了6种主要脂肪酸:肉豆蔻酸、棕榈油酸、棕榈酸、亚油酸、油酸、硬脂酸。分析了动物油与植物油在成分及相对含量上的差异,并且找出了动物油和植物油在不饱和度上的差别。根据动物油与植物油的差异点,可以对动物油和植物油进行区分。     

A computer program for the automatic identification of edible oils by gas—liquid chromatography

A computer program is given for the identification of edible oils from their fatty acid ratios. The program was used with the Hewlett-Packard 3354 Laboratory Automation System in autocall mode to identify a number of vegetable oils from the fatty acid ratios determined by gas chromatography of the trans-esterified oil samples.     

内标法测定甘油酯上的十一烷酸和13-甲基十四烷酸及其在非正常油脂掺伪识别中的应用

结合非正常油脂(地沟油)的来源(加热植物油和动物油)及反映其不同来源的重要特征指示物,即连接在甘油酯上的十一烷酸和13-甲基十四烷酸,建立了内标法测定油脂中甘油酯上十一烷酸和13-甲基十四烷酸的方法。多维气相色谱-质谱采用不分流进样和选择性切割可以实现在线净化和富集,提高分析的灵敏度和分离度。十一烷酸和13-甲基十四烷酸的方法检出限分别达到0.070、0.006 mg/kg。此外,研究发现绝大多数正常植物油中十一烷酸和13-甲基十四烷酸的含量比非正常油脂中二者的含量低。通过待测油脂中十一烷酸和13-甲基十四烷酸的含量可以在一定程度上推断食用植物油的品质。     

Comparative study of oxidative stability of sunflower and cotton biodiesel through P-DSC

Biodiesel can contain unsaturated fatty acids, which are susceptible to oxidation, being able to change into polymerized compounds. Oxidative stability is very important in the quality control of oils and biodiesel. In this study, biodiesel samples were produced through the methyl route, using a homogeneous catalyst. The determination of methyl esters was performed by gas chromatography in order to confirm the conversion of the carboxylic acids present in the raw material for the methyl esters. Also proved the presence of methyl linoleate and methyl oleate to the major constituent of biodiesel. The thermal and oxidative stability of sunflower and cotton oils and their biodiesel, using TG and P-DSC techniques were investigated. The use of P-DSC to measure the oxidative induction time was very important. These measurements were used to evaluate the cotton and sunflower oils, and their respective biodiesel. It was found that the thermal-oxidative stability of vegetable oils and their biodiesel were similar, due to the fact that both presented chemical composition and percentages of fatty acids similar.     

Cold-Pressed Pomegranate Seed Oil: Study of Punicic Acid Properties by Coupling of GC/FID and FTIR

Over the last decades, we have witnessed an increasing interest in food-related products containing vegetable oils. These oils can be obtained either by extraction or by mechanical pressing of different parts of plants (e.g., seeds, fruit, and drupels). Producers of nutraceuticals have ceaselessly searched for unique and effective natural ingredients. The enormous success of argan oil has been followed by discoveries of other interesting vegetable oils (e.g., pomegranate oil) containing several bioactives. This work describes the pomegranate fruit extract and seed oil as a rich source of conjugated linolenic acid as a metabolite of punicic acid (PA), deriving from the omega-5 family (ω-5). Through the chemical characterization of PA, its nutritional and therapeutic properties are highlighted together with the physiological properties that encourage its use in human nutrition. We analyzed the composition of all fatty acids with beneficial properties occurring in pomegranate seed oil using gas chromatography (GC) with flame-ionization detection (FID) analysis combined with Fourier transform infrared spectroscopy (FTIR). Pomegranate seed oil mainly consists of 9,11,13-octadic-trienoic acid (18:3), corresponding to 73 wt % of the total fatty acids. Nine components were identified by GC in PSO, varying between 0.58 and 73.19 wt %. Using midinfrared (MIR) spectroscopy, we compared the composition of pomegranate seed oil with that of meadowfoam seed oil (MSO), which is also becoming increasingly popular in the food industry due to its high content of long chain fatty acids (C20-22), providing increased oil stability. From the results of FTIR and MIR spectroscopy, we found that punicic acid is unique in PSO (73.19 wt %) but not in MSO.     

A novel approach to the rapid assignment of 13C NMR spectra of major components of vegetable oils such as avocado,mango kernel and macadamia nut oils

Assignment of ¹³C nuclear magnetic resonance (NMR) spectra of major fatty acid components of South African produced vegetable oils was attempted using a method in which the vegetable oil was spiked with a standard triacylglycerol. This proved to be inadequate and therefore a new rapid and potentially generic graphical linear correlation method is proposed for assignment of the ¹³C NMR spectra of major fatty acid components of apricot kernel, avocado pear, grapeseed, macadamia nut, mango kernel and marula vegetable oils. In this graphical correlation method, chemical shifts of fatty acids present in a known standard triacylglycerol is plotted against the corresponding chemical shifts of fatty acids present in the vegetable oils. This new approach (under carefully defined conditions and concentrations) was found especially useful for spectrally crowded regions where significant peak overlap occurs and was validated with the well‐known ¹³C NMR spectrum of olive oil which has been extensively reported in the literature. In this way, a full assignment of the ¹³C{1H} NMR spectra of the vegetable oils, as well as tripalmitolein was readily achieved and the resonances belonging to the palmitoleic acid component of the triacylglycerols in the case of macadamia nut and avocado pear oil resonances were also assigned for the first time in the ¹³C NMR spectra of these oils. Copyright © 2009 John Wiley & Sons, Ltd.     

Thermogravimetric investigations on the thermal degradation of bixin,derived from the seeds of annatto (<Emphasis Type=”Italic”>Bixa orellana L.</Emphasis>)

Conventional methods have been proposed to determine thermal properties of edible vegetable oils. The evaluation of the applicability of DSC and microwave oven (MO) methods to determine the specific heat capacities of the edible vegetable oils was performed. It was observed that the specific heat capacities of each edible oil increased as a function of the saturation of the fatty acids.     

Rosemary (Rosmarinus officinalis L.) extract

The restriction to the use of synthetic antioxidants has fostered the research on natural antioxidants, taking into account that the prolonged usage of these substances can harm seriously the human being provoking degenerative diseases. In the present study, the antioxidant effect of the ethanolic rosemary (Rosmarinus officinalis L.) extract on the oxidative stability of edible vegetable oils was investigated by means of the pressurized differential scanning calorimetry (PDSC) and oven test techniques. The rosemary extract, at the concentration of 2,000 mg kg^?1, as well as the synthetic antioxidant tert-butylhydroquinone (TBHQ) at the concentrations of 100 and 200 mg kg^?1 were added to samples of sunflower oil, corn oil, and soybean oil. The fatty acid profiles of the vegetable oils were determined by gas chromatography–mass spectrometry confirming the elevated contents of unsaturated fatty acids. The thermogravimetric analysis showed that the rosemary extract is stable at the frying temperature of the oils. The results of the oxidative stability demonstrated that the extract of Rosmarinus officinalis displayed a more effective protective action in the PDSC technique, when compared with the synthetic antioxidant TBHQ, indicating that it is a promising source of natural antioxidants for edible vegetable oils.     

Thermoplastic starch films with vegetable oils of Brazilian Cerrado

Starch is one of the most promising natural polymers to be abundant, cheap and biodegradable. To get thermoplastic starch (TPS) is necessary mechanical shake, high temperature and use of plasticizers. In this work, TPS films were prepared by casting from cassava starch and three different vegetable oils of Brazilian Cerrado as plasticizer: buriti, macauba and pequi. The materials were analyzed by TG, DSC and TMA. Thermal properties of oils depend on their chemical structures. Starch and vegetable oils are natural resources that can be used how alternative to producing materials that cause minor environmental impact.     

我国油料产品品质的近红外光谱快速检测技术研究进展

近红外光谱技术是一种快速无损检测技术,具有操作简单、检测成本低、无需化学试剂、绿色环保,以及可实现多品质参数同步检测等优点。该文综述了我国油料和食用植物油品质的近红外光谱速测技术研究进展,包括油料含油量、粗蛋白含量、脂肪酸含量等品质指标,食用油的理化指标,以及脂肪酸和食用油的真实性鉴别,并对油料产品品质的近红外光谱速测技术的发展前景进行了展望。     

气相色谱法与麻油纯度试验法在芝麻油掺伪鉴定中的应用

用气相色谱法和麻油纯度试验法对芝麻油掺伪情况进行分析。用气相色谱法分析脂肪酸组成,测定植物油中的主要脂肪酸,来确定是何种油或掺入其它何种植物油;麻油纯度试验法用于定量。两者可结合起来使用。     

High-resolution detection of adulteration of maize oil using multi-component compound-specific delta13C values of major and minor components and discriminant analysis

Maize oil commands a premium price and is thus a target for adulteration with cheaper vegetable oils. Detection of this activity presents a particular challenge to the analyst because of the natural variability in the fatty acid composition of maize oils and because of their high sterol and tocopherol contents. This paper describes a method that allows detection of adulteration at concentrations of just 5% (m/m), based on the Mahalanobis distances of the principal component scores of the delta(13)C values of major and minor vegetable oil components. The method makes use of a database consisting of delta(13)C values and relative abundances of the major fatty acyl components of over 150 vegetable oils. The sterols and tocopherols of 16 maize oils and 6 potential adulterant oils were found to be depleted in (13)C by a constant amount relative to the bulk oil. Moreover, since maize oil contains particularly high levels of sterols and tocopherols, their delta(13)C values were not significantly altered when groundnut oil was added up to 20% (m/m) and it is possible to use the values for the minor components to predict the values that would be expected in a pure oil; therefore, comparison of the predicted values with those obtained experimentally allows adulteration to be detected. A refinement involved performing a discriminant analysis on the delta(13)C values of the bulk oil and the major fatty acids (16:0, 18:1 and 18:2) and using the Mahalanobis distances to determine the percentage of adulterant oil present. This approach may be refined further by including the delta(13)C values of the minor components in the discriminant analysis thereby increasing the sensitivity of the approach to concentrations at which adulteration would not be attractive economically.     

Utilizing biotechnology in producing fats and oils with various nutritional properties

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.     

Rapid characterization of edible oils by direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis using triacylglycerols

Direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometric (MALDI-TOFMS) analysis of solutions of edible fats/oils yielded spectra useful for their rapid differentiation and classification. Results also reflected the individual fatty acid components and their degree of unsaturation. After dissolution in hexane, MALDI-MS analysis revealed spectra showing characteristic triacylglycerols (TAGs), the main fat/oil components, as sodium adduct ions. The Euclidean distances calculated using the mass and intensity values for 20 TAGs were used to evaluate and compare spectra. With cluster analysis, animal fats grouped together differently than vegetable oils and the individual oils grouped together by type. The ion abundances for the individual TAGs and their presumed compositions were used to approximate the overall fatty acid composition of canola, soybean, corn, olive and peanut oil, as well as lard. Using this approach the calculated fatty acid compositions and degree of unsaturation generally fell within about 4% of literature values. When the degree of saturation was compared with values calculated from the package labeling the differences were about 7%.     

Silver-phase high-performance liquid chromatography–electrospray mass spectrometry of triacylglycerols

Silver-phase chromatography hyphenated with on-line electrospray mass spectrometry can be applied to characterize triacylglycerols present in vegetable oils with respect to their degree of unsaturation, the position of the most unsaturated fatty acid and the carbon number (CN). The CN information obtained with silver-phase HPLC–ESP–mass spectrometry is complementary to the unsaturation information obtained by silver-phase HPLC-flame ionization detection. Both information is essential to monitor or study modified vegetable oils on the presence of non-natural triacylglycerols. The quantitative results obtained with the method are in agreement with the results obtained in the silver-phase HPLC-flame ionization detection and with theoretical values calculated from the fatty acid distribution of the oil. Silver-phase HPLC–ESP-mass spectrometry gives direct information on fatty acid position and triacylglycerol CN, for each of the triacylglycerols in the sample. This in contrast with non-aqueous reversed-phase HPLC hyphenated with on-line atmospheric pressure chemical ionization-mass spectrometry, which requires a more extensive data processing. The results obtained with silver-phase HPLC–ESP-mass spectrometry can be presented in a three-dimensional overview (relative amount, CN, fatty acid position) serving as a fingerprint for the oil.     

全二维气相色谱-四极杆质谱法检测植物油脂中脂肪酸

建立了植物油脂中31种脂肪酸成分的全二维气相色谱-四极杆质谱(GC×GC-qMS)分析方法。样品经甲酯化衍生后,以DB-1柱(30 m×0.25 mm×0.25 μm)作为一维柱、DB-Wax柱(3.2 m×0.1 mm×0.1 μm)作为二维柱组成柱系统进行分离,在调制周期为3.5 s、四极杆质量扫描范围为m/z 40～350的条件下,植物油脂中31种脂肪酸成分可以在50 min内得到准确和灵敏的检测。将本方法应用于实际样品的分析,灵敏度较传统的气相色谱-质谱法提高了100倍以上,一些植物油中微量的脂肪酸成分也因此被检出。该研究不仅为植物油中脂肪酸成分的分析提供了新的技术手段,同时对于确保食用植物油的质量安全、消除食用植物油的掺假伪劣等均有重要意义。     

ToF‐SIMS spectrometry to observe fatty acid profiles of breast tissues in broiler chicken subjected to varied vegetable oil diet

This study is aimed to observe changes in fatty acid profiles by time of flight secondary ion mass spectrometry (ToF‐SIMS) in breast muscle tissues of broilers. Four different groups were identified. The source of fat in group I was soy oil (rich in linoleic acid, ω‐6), group II received linseed oil (ω‐3), and the third group was fed a mixture of the two mentioned oils. Broilers in the control group were fed with beef tallow, used in mass commercial production. The results reveal that the use of vegetable oils in animal nutrition determines the lipid profile of fatty acids. ToF‐SIMS measurements showed that the lipid profile of muscle fibers and intramuscular fat reflect the composition of fats used as feed additives. In both structures, the ratio of ω‐6/ω‐3 fatty acids, which is most favorable for human health, was found in the groups in which a mixture of vegetable oils and a supplement of linseed oil were used.     

Lubricant properties of Moringa oil using thermal and tribological techniques

The increasing application of biobased lubricants could significantly reduce environmental pollution and contribute to the replacement of petroleum base oils. Vegetable oils are recognized as rapidly biodegradable and are thus promising candidates for use as base fluids in formulation of environment friendly lubricants. Although many vegetable oils have excellent lubricity, they often have poor oxidation and low temperature stability. Here in, we report the lubricant potential of Moringa oil, which has 74% oleic acid content and thus possess improved oxidation stability over many other natural oils. For comparison, Jatropha oil, cottonseed oil, canola oil and sunflower oil were also studied. Among these oils, Moringa oil exhibits the highest thermo-oxidative stability measured using PDSC and TG. Canola oil demonstrated superior low temperature stability as measured using cryogenic DSC, pour point and cloud point measurements. The friction and wear properties were measured using HFRR. Overall, it was concluded that Moringa oil has potential in formulation of industrial fluids for high temperature applications. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.