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This study aimed to determine the chemical properties (fatty acid composition, oil content, sterol and tocopherol compositions) of the oils extracted from the seeds of safflower (Dinçer, Remzibey, Balci, Linas, Yenice, Olas) varieties harvested in different periods from flowering to ripening period. In parallel with the increase of harvest time, the humidity rate decreased, while the oil ratios increased. It was determined that palmitic (16:0) and stearic (18:0) acids, which are significant saturated fatty acids, and oleic (18:1) and linoleic (18:2) acids, which are unsaturated fatty acids, are quite high in the oils of all safflower varieties. These fatty acids showed significant changes from the first harvest to the last harvest. The total saturated fatty acid ratios decreased, while the amount of unsaturated fatty acids increased as the maturation progressed. The first and latest harvest samples of Dinçer, Remzibey, Balcı, Linas, Yenice, Olas cultivars were selected and their sterol and tocopherol compositions were examined. The highest level of sterol in all cultivars was β‐sitosterol and the amount of sterols decreased towards full maturity. It was determined that α‐tocopherol was the dominant tocopherol found in the safflower oils and the amount of tocopherol increased towards full maturity. [ABSTRACT FROM AUTHOR]

Safflower oil‐based oleogels were produced from beeswax and rice bran wax. Oleogels demonstrated higher oxidative stability than shortening at the cooking temperature. Peroxide values in shortening, rice bran wax oleogels, and beeswax oleogels samples were found in the range of 4.8–27.76, 13.21–20.45 and 4.30–7.72 meqO2kg−1 oil. Following oleogelation, there was no significant change in fatty acid composition of safflower oil. In addition, after baking process, the changes in the major fatty acids were not determined to be significant. Solid fat content ratios (carried out at 35°C) of rice bran wax oleogels, in beeswax oleogels and in shortening samples were defined in the range of 4.10%–7.70%, 0.80%–5.00%, and 9.61%, respectively. The highest oil binding capacity was revealed in beeswax oleogels with 99.93%–99.98%. The shortest crystallization time was determined as 3 min in oleogel containing 10% rice bran wax. Cakes consisted of oleogel were acceptable in terms of texture and sensory properties compared to cake produced with shortening. Sensory results revealed that some cakes produced with oleogels were found to be more acceptable as compared with control group samples. In this respect, oleogels produced with safflower oil‐based beeswax and rice bran wax could be used instead of commercial solid fat widely used in the cake industry. [ABSTRACT FROM AUTHOR]

A simple generalization of the Hildebrand equation is presented for the prediction of the solid–liquid phase diagram of a binary mixture of structuring agents dissolved in an inert liquid. The model is a thermodynamic interpolation between three well‐known limits: (1) the freezing depression curve of liquid A under influence of the addition of the solvent, (2) the freezing depression curve of liquid B under influence of the addition of the solvent, and (3) the binary solid–liquid phase diagram of substances A and B. The theory is shown to be valid as long as the freezing temperature of the liquid is well below the freezing temperatures of the structurants. The theory is compared to literature data for three different mixtures: (1) stearyl alcohol and stearic acid dissolved in sunflower oil, (2) hentriacontane+melissic acid in safflower oil, and (3) lauric acid + behenic acid in canola oil. The agreement between the thermodynamic calculation and experimental data is good. The solid–liquid phase behavior of glyceryl tristearate + stearic acid in edible oil is also studied. The location of the eutectic point of the latter system is predicted to shift toward an axis with zero tristearate concentration as the structurant concentration decreases from 50% to 5% (w/w). [ABSTRACT FROM AUTHOR]

The crystallization behavior and structure of mixtures of a high behenic acid stabilizer (HBS) in peanut oil, high oleic safflower oil and sesame oil were studied in order to elucidate the mechanism behind liquid oil stabilization. Both the chemical composition of the oil and cooling rate influenced the crystallization behavior and structure of HBS. The critical gelation concentration of HBS ranged from 6.5% for peanut oil crystallized at 3 °C/min to 11% for sesame oil mixtures crystallized at 0.6 °C/min. The free energy of nucleation (Δ G) was the highest for sesame oil (142 kJ/mol) followed by high oleic safflower oil (75.8 kJ/mol) and peanut oil (15.9 kJ/mol). The HBS peanut oil mixture displayed the highest storage modulus ( G′) under both cooling rates studied. In general, HBS-oil mixtures crystallized at a higher cooling rate exhibited high SFC values, lower crystallization temperatures and a predominance of the β′ polymorph, and they had a microstructure characterized by uniformly sized spherulites. In contrast, slow cooling rates led to higher critical gelation concentrations of HBS, lower SFC, fractionation of higher melting and lower melting fractions, a more stable polymorphic form β and a wide range of spherulite sizes. [ABSTRACT FROM AUTHOR]

Safflower ( Carthamus tinctorius L.) is one of the oldest domesticated crops, mainly grown as oilseed in the arid and semi arid regions of the world. Cross-ability of Carthamus species has made wild safflower species a suitable source for transferring drought tolerant genes to cultivated species. This study was conducted to investigate seed yield per plant, oil content and fatty acid composition of some Carthamus species and to identify the effects of drought stress on these measured traits. In this regard, 27 genotypes from C. tinctorius, C. palaestinus, C. oxyacanthus, C. lanatus and C. glaucus were planted in the field under normal and drought-stress conditions for two years. Results showed that some studied species differed in oil content, seed yield per plant and fatty acid profiles. As an example, the highest seed oil content (32%) was found in genotype number 22 from C. palaestinus, and the lowest (18%) was obtained for the genotype number 11 from C. lanatus. For all the species, oil content was not affected by moisture stress and did not change over different environments. Similar and stable responses of various Carthamus species for fatty acid composition indicated that hybridization between these species for genetic improvement of drought tolerance may have no adverse effects on oil quality. Considerable diversity within species for all measured traits, similarity in fatty acid profiles and almost the same pattern of changes under drought stress showed that the wild species especially the crossable ones, are good candidates to be used in breeding of cultivated safflower. [ABSTRACT FROM AUTHOR]

Inexpensive and rapid methods for measurement of seed oil content by near infrared reflectance spectroscopy (NIRS) are useful for developing new oil seed cultivars. Adopting default multiple linear regression (MLR), the predictions of safflower oil content were made by 20-140 samples using a Perten Inframatic 8620 NIR spectrometer. Although the obtained interpolation results of MLR had desired accuracy, the extrapolation was extremely poor. The extrapolation determination coefficient ( R) and standard error (SE) of cross validation for MLR models were 0.63-0.78 and 3.71-4.44, respectively. In order to overcome the accuracy limitation of linear MLR models, a common suggestion is to use a nonlinear artificial neural network (ANN); however, it needs a large number of data to yield significant accurate results. We developed a novel robust hybrid fuzzy linear neural (HFLN) network to capture simultaneously linear and nonlinear patterns of data with a limited number of safflower samples. Empirical extrapolation results showed that the HFLN had higher R (=0.85) and lower SE (=1.83) compared to those obtained by MLR and ANN models. It is concluded that hybrid methodologies could be used to construct efficient and appropriate models for estimation of seed oil content set up on NIR system. [ABSTRACT FROM AUTHOR]

The objective of the research was the synthesis of linoleic acid hydroperoxides (HPOD) and their recovery, using selected sources of linoleic acid (LA) as substrate. This is part of on-going work aimed at the development of an economically viable biotechnological process for the production of natural flavors. The investigated sources included pure (100 %) LA and commercial (67 %) LA as well as safflower oil (SO) and its hydrolyzed product. A model describing commercial LA oxidation by lipoxygenase, based on Michaelis-Menten kinetics, was developed. The conversion of pure LA and commercial LA resulted in insignificant differences in HPOD yield of 69.7 and 68.9 %, respectively. However, there was a significant difference in the HPOD yield, obtained from the SO (2.0 %) and that from the hydrolyzed SO (58.0 %) in comparison to that from pure LA (69.7 %). The ratios of the different 9- and 13-HPOD isomers were insignificantly different for the sources containing free LA, with 13-(9 Z,11 E)-HPOD was the highest relative percentage. Using optimized conditions, HPOD yields were 85.9 and 74.0 % for the commercial LA and the hydrolyzed SO, respectively. Based on experimental findings, commercial (67 %) LA was selected as the most appropriate alternative to pure LA for the production of HPOD. An efficient extraction procedure for the recovery of HPOD was also developed. [ABSTRACT FROM AUTHOR]

In this study, seeds from the safflower variety called 'Dinçer' were roasted and microwaved before oil extraction by cold pressing. Some physico-chemical analyses (moisture, ash, oil content and color) were performed in safflower meals. Physico-chemical properties (refractive index, viscosity, turbidity, specific gravity, color, free acidity, peroxide value, iodine number), nutritional components (total phenolics, antioxidant capacity, tocopherol content), sterol composition and fatty acid composition of produced oils were also determined. Volatile components of the oils were detected by solid-phase microextraction/gas chromatography-mass spectrometry technique. Quantitative descriptive analysis was accomplished with trained panelists by 11 definition terms. Cold pressing yielded less oil than solvent extraction, but oil quality was superior and a refining process was not required. There was no significant difference between samples for fatty acid composition and some physico-chemical parameters. Whereas, microwave treatment caused a decrease in oil turbidity, free acidity, α-tocopherol and some sterol contents and an enhancement in total phenolic content, antioxidant capacity and peroxide value. Moreover, microwave treatment led to an increased nutty aroma in the oil. In contrast, isot pepper aroma was decreased by microwave treatment. This study provides very important information about the safflower oils for the first time in the literature. [ABSTRACT FROM AUTHOR]

Near-infrared reflectance spectroscopy (NIRS) of intact seeds allows the non-destructive estimation of seed quality parameters which is highly desirable in plant breeding. Together with yield, oil content and quality, a main aim in safflower ( Carthamus tinctorius L.) breeding is the selection of genotypes with a low percentage of empty seeds even under cooler climates. We developed NIRS calibrations for seed oil content, oleic and linoleic acid content, the seed hull fraction and the percentage of empty seeds using seed meal and intact seeds. For the different calibrations 108-534 samples from a safflower breeding program with lines adapted to German conditions, were analyzed with reference analyses (Soxhlet, gas chromatography), and scanned by NIRS as intact seeds and seed meal. Calibration equations were developed and tested through cross validation. The coefficient of determination of the calibration ( R) for intact seeds ranged from 0.91(oil content), 0.90 (seed hull fraction), 0.84 (empty seeds), 0.73 (linoleic acid) to 0.68 (oleic acid). The coefficient of determination of the cross validation was higher for seed meal than for intact seeds except for the parameter seed hull fraction. The results show that NIRS calibrations are applicable in safflower breeding programs for a fast screening. [ABSTRACT FROM AUTHOR]

The F and F progenies of eight-parent diallel crosses were used to investigate the mode of inheritance of fatty acids, oil, and protein in safflower ( Carthamus tinctorius L.) seeds. The results indicated significant differences among the parents for general (GCA) and specific combining ability (SCA). Relatively high narrow-sense heritability was estimated for fatty acids including linoleic (0.84), oleic (0.77), palmitic (0.61), and stearic (0.6) acids. The high narrow-sense heritability and the high ratio of GCA/SCA mean squares for all the fatty acids investigated indicate the important role of additive gene action in controlling these traits. In our experiment, however, low narrow-sense heritability was obtained for oil (0.37) and protein (0.28) contents. Furthermore, the estimates of genetic variance components proposed the importance of non-additive genetic effects that contribute to variation in oil and protein content. The overall results indicated that K × Mex.22-191 cross could be employed for the production of high oil yielding and high oleic acid safflower lines in breeding programs. [ABSTRACT FROM AUTHOR]

We have studied the pre-nucleation behavior of tripalmitin (TP) and tristearin (TS) in blends with triolein (TO), high oleic safflower oil (HOSfO) and soybean oil (SBO) by means of fluorescence polarization spectroscopy (FPS) and molecular mechanics simulations (MM). The FPS measurements at different temperatures showed that there is an increase in the anisotropy of the TP:HOSfO and TP:SBO blends as opposed to the TP:TO sample. This increase is directly related to an increase in the microviscosity of the blend which is interpreted as a structuring step prior to the nucleation and growth of the crystals. A similar but less pronounced effect was also observed in the TS:SBO blends. We performed MM simulations in an attempt to understand the molecular interactions responsible for this behavior. The simulation results have shown that short range van der Waals (vdW) interactions are the ones responsible for the increase in the microviscosity of the blends prior to crystallization. Our results also indicate that the presence of molecules that contain at least one chain of palmitic acid in their triglyceride (TAG) composition will induce a pre-nucleation increase in the microviscosity of the blend in both TP and TS containing systems. Lastly, we studied the applicability of these conclusions to longer chain TAG analogues. Our MM results show that hypothetical blends of TS and TAGs containing stearic acid in their structure, will not have a low enough vdW energy to account for an increase in the microviscosity. Hence, there seems to be a specific interaction particularly favorable when the oil contains TAGs with at least one palmitic acid chain. [ABSTRACT FROM AUTHOR]

Safflower oil contains a large amount of unsaturated fatty acids, however, the composition of the oil may be affected by drought stress. This experiment determined the effect of three irrigation regimes (60, 75 and 90% soil moisture depletions of available water) on oil composition of safflower cultivars (Kuseh, PI and IL111). Amounts of oil and oil composition of the seeds were determined by gas chromatography (GC). The oil contents of IL111, PI and Kuseh cultivars were 30.73, 27.63 and 25.25%, respectively. The oil contents, palmitic, stearic, oleic and linoleic acid contents were reduced by about 13, 63, 60, 14 and 10% by drought, respectively. The stearic acid contents of PI, IL111 and Kuseh were reduced by 72, 61 and 37% and palmitic acid contents of the same cultivars were reduced by drought by 65, 53 and 51%, respectively. Whereas, the linoleic acid contents of Kuseh, PI and IL111 were reduced by only 10, 8 and 5% and oleic acid contents of the same cultivars were reduced by only 14, 13 and 14% under the drought stress, respectively. The results showed that although drought stress reduced the amount of oil and oil composition of safflower cultivars, the decrease was due to a dramatic reduction in saturated fatty acids contents. Thus, proper irrigation regimes may enhance safflower oil quality. [ABSTRACT FROM AUTHOR]

The oxidative stability of conventional and high-oleic varieties of commercial vegetable oils, with and without added antioxidants, was evaluated using the oil stability index (OSI). Oil varieties studied were soybean (SOY), partially-hydrogenated soybean (PHSOY), corn (CORN), sunflower (SUN), canola (CAN), high-oleic canola (HOCAN), very high-oleic canola (VHOCAN), oleic safflower (SAF) and high-oleic sunflower (HOSUN). One or more commercial antioxidants were added to the four most stable oils at supplier-recommended levels: rosemary extract (RM; 1,000 ppm), ascorbyl palmitate (AP; 1,000 ppm), tert-butylhydroquinone (TBHQ; 200 ppm), and mixed tocopherols (TOC; 200 ppm). OSI in hours (h) at 110 °C of the conventional oils were 5.2, 7.6, 8.4, 9.8, 10.9 and 14.3 h for SUN, SOY, CAN, CORN, PHSOY and SAF, respectively. OSI of high-oleic variants were 12.9, 16.5 and 18.5 h for HOCAN, HOSUN and VHOCAN, respectively. Maximum OSI values for the four most stable oils when treated with antioxidants, were 40.9, 48.5, 48.8 and 55.7 h for HOCAN, VHOCAN, SAF and HOSUN, respectively. Addition of TBHQ, alone and in combination with other antioxidants, resulted in the greatest increase in oxidative stability of SAF and other high-oleic oils evaluated. AP had a positive synergistic effect when used with TBHQ, while RM decreased TBHQ effectiveness. [ABSTRACT FROM AUTHOR]

Seeds of six safflower (C. tinctorius L.) genotypes and 19 accessions of two wild species were analyzed for oil and fatty acid composition. Oil content ranged from 29.20 to 34.00, 20.04 to 30.80 and 15.30 to 20.80% in C. tinctorius, C. oxyacantha Bieb. and C. lanatus L., respectively. The main fatty acids of oleic, linoleic, palmitic and stearic acids composed 96-99% of the total fatty acids in all species. The sum of myristic, palmitoleic, arachidic, and behenic fatty acids in oil of the species ranged from 0.43 to 0.57%. The oleic acid in seed oil of C. tinctorius, C. oxyacantha and C. lanatus ranged from 12.24 to 15.43, 14.11 to 19.28 and 16.70 to 19.77%, respectively. The corresponding ranges for linoleic acid were 71.05 to 76.12, 63.90 to 75.43 and 62.47 to 71.08%. Palmitic acid in seed oil varied from 5.48 to 7.59% in C. tinctorius, 6.09 to 8.33% in C. oxyacantha and 7.44 to 8.78% in C. lanatus. The stearic acid of the seed oil showed a variation of 1.72 to 2.86, 2.50 to 4.87 and 3.14 to 4.79% in genotypes of these species, respectively. The fatty acids composition of oil among the cultivated and wild species were not considerably different, indicating that seed oil of the wild safflower is possibly suitable for human consumption and industrial purposes. [ABSTRACT FROM AUTHOR]

Low trans fatty acid basestocks suitable for blending with liquid oils to make spreads and shortenings are prepared by using a two-step hydrogenation process. The first step uses a nickel catalyst to hydrogenate soybean, canola, high-oleic sunflower, and high-oleic safflower oils to a predetermined iodine value. At this point in the reaction, the second step commenced. Addition of a platinum catalyst at 80 °C and 73 psi hydrogen pressure allowed for hydrogenation to proceed to iodine values of 40-50. These products had 11-18% trans fatty acid content. These were then blended with soybean oil (5-50% basestock) to give products with bulk properties similar to commercial spreads and shortenings but with about one third the levels of trans fat. [ABSTRACT FROM AUTHOR]

Fatty acid composition and moisture and oil content were determined for Montola-2001 and Centennial safflower varieties at three different harvest dates from flowering to maturity, which were grown as autumn and spring crops in two different locations in 2001-2002 and 2002-2003. The experiment was carried out using split-split plots in a randomized complete block design with three replicates. Sowing dates affected oil content and fatty acid compositions significantly (P < 0.01), whereas moisture content in both years was not significantly affected. Moisture content declined 15 days from flowering period to maturity, while oil content increased. The rate of the palmitic acid formation decreased in both varieties 15 days from flowering period to maturity, whereas formation rates of the oleic and linoleic acids increased in Montola-2001 and Centennial varieties, respectively. [ABSTRACT FROM AUTHOR]

The compositions of rice bran oils (RBO) and throe commercial vegetable oils were investigated. For refined groundnut oil, refined sunflower oil, and refined safflower oil, color values were 1.5 2.0 Lovibond units, unsaponifiable matter contents were 0.15-1.40%, tocopherol contents were 30-60 mg%, and FFA levels were 0.05 0.10%, whereas refined RBO samples showed higher values of 7.6-15.5 Lovibond units for color, 2.5 3.2% for unsaponifiable matter, 48-70 mg% for tocopherols content, and 0.14-0.55% for FFA levels. Of the four oils, only RBO contained oryzanol, ranging from 0.14 to 1.39%. High-oryzanol RBO also showed higher FFA values compared with the other vegetable oils studied. The analyses of FA and glyceride compositions showed higher palmitic, oleic, and linoleic acid contents than reported values in some cases and higher partial glycerides content in RBO than the commonly used vegetable oils. Consequently, the TG level was 79.9-92% in RBO whereas it was >95% in the other oils studied. Thus, refined RBO showed higher FFA values, variable oryzanol contents, and higher partial acylglycerol contents than commercial vegetable oils having lower FFA values and higher TG levels. The higher oryzanol levels in RBO may contribute to the higher FFA values in this oil. [ABSTRACT FROM AUTHOR]

Studies were conducted to investigate whether adsorption of amphiphiles from oil onto a degreased metal can be predicted from knowledge about adsorption of the amphiphiles at the oil-water interface. The surface of a degreased metal comprises oxides, hydroxides, and adsorbed water vapor, which form from the reaction of the metal with air and moisture. If the behaviors of amphiphiles at water-oil and metal-oil interfaces are similar, this information can be useful in the development of cheaper and quicker methods of estimating amphiphile adsorption properties on degreased metals. The amphiphiles used were safflower oil (SA) and jojoba oil (JO), both of which are plant-based oils, and methyl palmitate (MP). SA is a triester whereas JO and MP are monoesters. The interfacial tension of water-hexadecane was measured as a function of amphiphile concentration in hexadecane and used to estimate an interfacial-based free energy of adsorption, ΔGads. The resulting interfacial-based ΔGads values for SA were identical to those reported from friction-based adsorption isotherms. The corresponding values for the monoesters were within the range reported from friction-based adsorption isotherms. [ABSTRACT FROM AUTHOR]

Response surface methodology is a statistical design that helps one to determine optimal conditions for an enzyme-catalyzed reaction by performing a minimal number of experiments. This methodology was adapted for modifying coconut oil TAG by using lipase-catalyzed acidolysis in hexane to incorporate n−3 or n−6 PUFA. FFA obtained after hydrolysis of cod liver oil and safflower oil were used as acyl donors. Immobilized lipase, Lipozyme IM60, from Rhizomucor miehei was used for catalyzing the reaction. The reaction conditions—substrate molar ratio, incubation time, and temperature—were optimized. The experimental data were fitted to a response function based on the central composite rotatable design. The optimal conditions generated from models indicated that maximal incorporation of n−3 PUFA occurred at a 1∶4 molar ratio of TAG/FFA when incubation was carried out for 34 h at 54°C. Similarly, maximal incorporation of n−6 FA was predicted at a 1∶3 molar ratio of TAG/FFA when incubated for 48.5 h at 39°C. Experiments conducted at optimized conditions predicted by the equation obtained from response surface methodology yielded structured lipids with 13.65 and 45.5% of n−3 and n−6 FA, respectively. These values agreed well with that predicted by the model. The reactions were also scaled up to 100 g levels in batch reactors with the incorporation level of n−3 and n−6 fatty acids agreeing closely with that observed when the reactions were carried out at lab scale (100 mg). These studies indicated that response surface methodology is a useful tool in predicting the conditions for incorporating desired levels of specific FA during the synthesis of structured lipids. [ABSTRACT FROM AUTHOR]

An attempt was made to produce structured lipids containing essential fatty acid by acidolysis with 1,3-positional specific Rhizopus delemar lipase. The lipase was immobilized on a ceramic carrier by coprecipitation with acetone and then was activated by shaking for 2 d at 30°C in a mixture of 5 g safflower or linseed oil, 10 g caprylic acid, 0.3 g water and 0.6 g of the immobilized enzyme. The activated enzyme was transferred into the same amount of oil/caprylic acid mixture without water, and the mixture was shaken under the same conditions as for the activation. By this reaction, 45-50 mol% of the fatty acids in oils were exchanged for caprylic acid, and the immobilized enzyme could be reused 45 and 55 times for safflower and linseed oils, respectively, without any significant loss of activity. The triglycerides were extracted with n-hexane after the acidolysis and then were allowed to react again with caprylic acid under the same conditions as mentioned above. When acidolysis was repeated three times with safflower oil as a starting material, the only products obtained were 1,3-capryloyl-2-linoleoylglycerol and 1,3-capryloyl-2-oleoyl-glycerol, with a ratio of 86∶14 (w/w). Equally, the products from linseed oil were 1,3-capryloyl-2-α-linolenoyl-glycerol, 1,3-caprylol-2-linoleoyl-glycerol, and 1,3-capryloyl-2-oleoly-glycerol (60∶22∶18, w/w/w). All fatty acids at the 1,3-positions in the original oils were exchanged for caprylic acid by the repeated acidolyses, and the positional specificity of Rhizopus lipase was also confirmed to be strict. [ABSTRACT FROM AUTHOR]

The oxidative stability of five different oils was determined by Rancimat analysis with conductivity and chemiluminescence measurements for evaluation of the induction periods. Samples of oil, taken at intervals from the Rancimat apparatus, were used for chemiluminescence measurements. The chemiluminescence results were plotted vs. time, and the resulting curves were evaluated with a graphical tangential procedure in the same way as the curves of the Rancimat method (conductivity measurement). Induction periods of the oils assessed by Rancimat and chemiluminescence methods showed a significant linear correlation ( r=0.9865). The temperature dependence of the induction periods evaluated by chemiluminescence and by conductivity was investigated with walnut oil. A marked temperature dependence was observed for both. [ABSTRACT FROM AUTHOR]

Effects of microwave heating on the oxidative stability of d-tocopherols were studied in relation to the production of fatty acids in oils. During microwave heating, the stability of tocopherols decreased in the order δ> β> γ> α. This order did not depend on the types of ethyl esters of fatty acids or oils present. But, the shorter the chainlength and the lower the degree of unsaturation of the fatty acid ethyl esters, the greater was the reduction in amount of individual tocopherols. A similar tendency was observed when tocopherol-stripped vegetable oils, with equimolar mixtures of tocopherols added, were treated under the same conditions. The reduction in tocopherols became greater with increasing levels of free fatty acids. [ABSTRACT FROM AUTHOR]

Catalytic transfer hydrogenation (CTH) of safflower oil was studied using aqueous ammonium formate as hydrogen donor and palladium on carbon as catalyst in a closed vessel under controlled microwave irradiation conditions. The method offered good selectivity in complete reduction of linoleic acid to monounsaturated acid with a slight increase in stearic acid compared to other reported catalytic transfer hydrogenation methods. Selectivity was achieved by using microwave-assisted CTH without employing an emulsifier or high ratios of water to oil. [ABSTRACT FROM AUTHOR]

Synthetically prepared mixtures of conjugated linoleic acid (CLA) are widely used in animal and cell culture studies to investigate the potential effects of the Δ9 c, 11 t-18:2 isomer found in food products from ruminant animals. Alkali isomerization of linoleic acid is a common method used in the synthesis of a mixture of CLA isomers containing predominantly the Δ9 c, 11 t-18:2 and Δ10 t, 12 c-18:2 isomers. Some biological activity might also be mediated by the Δ10 t, 12 c-18:2 isomer. Currently few published methodologies exist describing procedures for the enrichment of these two isomers. A method is described herein to take advantage of an inexpensive oil, safflower oil, for use in synthesis of CLA and a procedure to enrich the Δ10 t, 12 c-18:2 isomer. [ABSTRACT FROM AUTHOR]