Removal of waxes from sunflower seed oil by miscella refining and winterization

Miscella refining and winterization produced a sunflower seed salad oil that did not cloud on refrigeration for 7 days. Refining reduced phospholipid content, and this facilitated wax removal during winterization.     

Solvent winterization of partially hydrogenated soybean oils

Among the important advantages of solvent as compared with conventional winterization of soybean oil are the speed of operation and increased yields up to 25%. Easier and faster filtration results with the solvent system despite the high yields of solids when low iodine value (IV) oils are winterized at low temperatures. Hydrogenated stocks with IV as low as 90 can be winterized easily at temperatures of −16C. The time of winterization can be reduced from several days to a few hours. With all the variations possible in IV, temperature, and solvent selectivity, liquid soybean oil can be produced with specified characteristics and with a minimum linolenate content. Acetone was the best solvent tested for winterization. Presented at AOCS meeting in New Orleans, La., 1964. A laboratory of the No. Utiliz. Res. and Dev. Div., ARS, USDA.     

Determination of wax concentration in sunflower seed oil

Isothermal crystallization of waxes was studied by using an optical setup. The induction time of crystallization was assessed as a function of wax concentration. The relationship was found to be a decreasing exponential curve. The wax content of some of the solutions prepared in the laboratory was determined by calculating the crystallization induction time. The values obtained were compared to those from different methods (cold test, microscopic, and turbidimetric methods). The results obtained with the optical setup method are similar to those obtained with other methods for concentrations greater than 100 ppm. An analysis of variance test was used to verify the authenticity of the values obtained with the optical method. Results showed that the method used to determine wax concentration, the concentration of the sample, and the relationship between both parameters do not affect significantly the values of percentage relative errors (P<0.05) obtained for concentrations greater than 100 ppm. Values obtained for wax content within the range 0–100 ppm could not be compared since the microscopic and turbidimetric methods are not sensitive enough, unlike the optical setup, to detect wax amounts in such low concentration.     

Almost complete dehulling of high oil sunflower seed

An almost complete dehulling (hull residue lower than 3%) of sunflower seeds, before oil extraction, reduces to a minimum both the transfer of pigments from hulls to the flour and the content of fiber in the finished product. In this paper some results of our work on the dehulling of high-oil seeds with an air-jet impact huller are presented. The effectiveness of dehulling has been evaluated as a function of characteristics of the seed (variety, moisture and so forth) and of operative parameters (impact velocity, etc.). The optical analysis of the impact of the seeds on the target was made optical analysis of the impact of the seeds on the target was made by means of high-speed cinematography (about 8000 frames/sec) to have a better view of the phenomenon and to measure the parameters of energy involved. The use of proper seed monentum, which is a function of the characteristic of the seed, can allow selective hull breaking with minimum kernel breakage. Almost complete hull-free kernels from high-oil sunflower seeds were obtained by means of a continuous dehuller-separator pilot plant.     

Stereospecific analysis of TAG from sunflower seed oil

Stereospecific analysis of TAG from a sunflower seed oil of Tunisian origin was performed. The TAG were first fractionated according to chain length and degree of unsaturation by RP-HPLC. The four major diacid- and triacid-TAG fractions were palmitoyldilinoleoyl-glycerol, dioleoyllinoleoylglycerol, oleoyldilinoleoylglycerol, and palmitoyloleoyl-linoleoyl-glycerol, amounting to 7.2, 16.6, 29.5, and 12 mol%, respectively. The TAG of the four fractions were individually submitted to stereospecific analysis, using a Grignard-based partial deacylation, separation of sn-1,2(2,3)-DAG from sn-1,3-DAG by boric acid-impregnated silica gel TLC plates, conversion of the sn-1,2(2,3)-DAG to their 3,5-dinitrophenylurethane (DNPU) derivatives, fractionation of DNPU derivatives by RP-HPLC, resolution of the DNPU-DAG by HPLC on a chiral column, transmethylation of each sn-DNPU-DAG fraction, and analysis of the resulting FAME by GC. The data obtained were used to determine the triacyl-sn-glycerol composition of the main TAG of the oil. Fifteen triacyl-sn-glycerols were identified and quantified, representing, along with the monoacid-TAG, trilinoleoylglycerol and trioleoylglycerol, more than 90% of the total oil TAG. The two major triacyl-sn-glycerols were trilinoleoyl-glycerol and 1-linoleoyl-2-linoleoyl-3-oleoyl-glycerol (18.6 and 18.5% of the total, respectively). Results clearly identified linoleic acid as the major FA at the sn-2 position, whereas oleic and palmitic acids were the major FA at the sn-3 position. The sn-1 position was occupied to nearly the same extent by linoleic and oleic acids, and to a greater extent by palmitic acid, which was practically absent at the sn-2 position.     

葵花籽油酯交换研究

以葵花籽油为原料,KOH作催化剂,对葵花籽油与甲醇进行酯交换反应研究,寻求酯交换反应的最佳条件。     

Rapid determination of wax in sunflower seed oil

A rapid turbidimetric method for determining wax content in sunflower seed oil is described. Oil is heated to 130 C, filtered, and after cooling, added to an equal volume of acetone. The mixture is then reheated under tap water to dissolve waxes which may have crystallized and is placed in an ice bath for 5 min. Turbidity is then measured and ppm wax is read from a previously prepared calibration curve. The amount of wax as determined by the turbidimetric method is in good agreement with the gas liquid chromatographic values. An erratum to this article is available at .     

Composition of organic and conventionally produced sunflower seed oil

The aim of the present study was to highlight the main differences between seed oils produced from conventionally cultivated crops and organically cultivated ones and processed using mild extraction procedures. The composition and the nutritional and health aspects of both types of sunflower seed oils were compared and were analytically tested to determine the macroscopic differences in proximate composition, the main differences in the minor components, the main quality parameters, the in vitro antioxidant activity, and the presence of trans-ethylene steroisomers in FA. No significant trends were found in the oil samples for TAG and FA composition, but remarkable differences were found in the composition of minor components and in the main chemical and analytical quality properties. The organically grown samples had a higher total antioxidant activity compared with the conventional samples. Trans FA were found only in the conventional oils.     

Flavor and oxidative stability of northern-grown sunflower seed oil

Flavor and oxidative stabilities of a northern-grown sunflower seed oil were investigated. Taste panel and oxidative evaluations were made on alkali-refined, deodorized, unbleached samples treated with commercial antioxidant mixtures, phenolic antioxidants, metal scavengers and added trace metals. Similar evaluations were conducted on a sample of the same oil after bleaching. Commercial antioxidant mixtures containing both phenolic antioxidants and a metal scavenger improve the flavor and oxidative stabilities of refined unbleached oil. Although phenolic antioxidants alone improve oxidative stability as measured by the active oxygen method test, flavor stability did not improve significantly for antioxidant-treated refined, unbleached samples after accelerated storage. Conversely, alkali-refined and bleached sunflower oil responded to treatment with certain phenolic antioxidants. Although iron and copper are deleterious to oil stability at concentrations of 0.1 ppm, such metal-inactivating agents as citric acid are effective in improving flavor stability. N. Market. Nutr. Res. Div., ARS, USDA.     

Tertiary butylhydroquinone as antioxidant for crude sunflower seed oil

This study indicates that crude sunflower seed oil is very susceptible to oxidation; thus prolonged storage should be avoided. Protection of the crude oil with a potent antioxidant such as tertiary butylhydroquinone (TBHQ) would seem both practical and beneficial. Discoloration which develops in the crude oil with or without TBHQ can be removed by proper selection of bleaching materials. Additional benefits to be derived from using TBHQ should be investigated by using test methods designed to study subtle flavor qualities of deodorized oils. Presented at the AOCS Meeting, Houston, May 1971.     

Partial hydrogenation and winterization of soybean oil

Soybean oil was hydrogenated under selective and nonselective conditions to give products with iodine values (I.V.) ranging from 85-115. The products were crystallized at 8C and examined for yield, stability, and fatty acid composition of the winterized oil. Changes in fatty acid composition, formation oftrans acids, and yield of winterized oil are approximately linear with the degree of hydrogenation. Stearine fractions, which are 15-20 I.V. units lower than winterized oil, were further crystallized in solvents to yield liquid oils and hard stearines. Presented at AOCS meeting, Toronto, Canada, October 1962 A laboratory of the No. Utiliz. Res. and Dev. Div., ARS, USDA     

Analysis of oil content of sunflower seed by wide-line NMR

The wide-line nuclear magentic resonance (NMR) analyzer is routinely used to determine the oil content of sunflower seed by plant breeders. This technique is now under consideration as the official method for the domestic trading of sunflower seed. A study of the effect of depth (volume) of sunflower seed in the NMR 130 ml sample tube showed that between a depth of 30–75 mm (23.5–62.5 g seed) the NMR response was uniform, but beyond 75 mm, the response rapidly decreased. Oil analysis of 10 sunflower seed samples showed that coefficient of variation (C.V.) was lower with a 130 ml sample tube (C.V. 0.4%) than with a 34 ml tube (C.V. 0.8%). As the temperature of the sample was increased 1C, the instrument response decreased by 0.4%. Analysis of sunflower seed with 31–71% linoleic acid contents analyzed 0.1% higher for each 1% decrease in linoleic acid. Data show that linoleic acid content of NMR sunflower seed standard is important in NMR total oil analysis. Results of this study showed that the sample of sunflower seed for total oil analysis by NMR should be contained at least within the bottom 70 mm of the 130 ml sample tube, and NMR response of the standard calibration seed and sample being analyzed should be read at the same temperature, and their fatty acid compositions should be similar.     

Tocopherol—An intrinsic component of sunflower seed oil bodies

Oil bodies were removed from mature sunflower through wet grinding followed by filtration then centrifugation and recovered as the buoyant fraction. Washing this fraction with buffer (water-washed oil bodies, WWOB) or 9 M urea (urea-washed oil bodies, UWOB) resulted in the removal of extraneous proteins. SDS-PAGE of the proteins still associated with the oil body fraction after washing indicated that this effect was particularly dramatic with urea washing. Thirty-eight percent of the total seed tocopherol was recovered in WWOB after only one cycle of oil body recovery. The total phenolic content (TPC) of differentially washed sunflower seed oil bodies was used as a marker for the nonspecific association of phenolic compounds to oil bodies. This value decreased with increased removal of proteins from oil bodies, whereas the converse was true for tocopherol values, which increased from 214 mg total tocopherol kg⁻¹ WWOB [dry wt basis (dwb)] to 392 mg total tocopherol kg⁻¹ UWOB (dwb). The ratio of the four tocopherol isomers remained constant in the seed and oil body preparations (α:β:γ:δ approximately 94∶5∶0.5∶0.5). This work provides evidence that an intrinsic population of tocopherol molecules exists in the oil bodies of mature sunflower seeds.     

Effects of drying on sunflower seed oil quality and germination

Sunflower seed (SunGro 380) were harvested 101 to 121 days after planting, and their moisture levels were between 43 and 15%. The seed were dried at 35, 53, 72, and 88 C to a final moisture level of 10% or below. Drying air flow was 2000 m³/hr./m³ seed. Temperature had no effect on peroxide values, total oil, or fatty acid composition. Free fatty acids increased as initial moisture decreased. For a given drying temperature, germination increased with decreasing initial moisture, and for a given initial moisture, germination increased with decreasing drying temperature. This study indicates that a drying temperature greater than 53 C should not be used if seed viability is to be maintained.     

Comparative study of methods of determining oil content of sunflower seed

An extraction-gravimetric method (AOCS Official Method Ai 3-75) was compared with 2 instrumental techniques, near-infrared reflec-tance (NIR) spectroscopy and wide-line nuclear magnetic resonance (NMR), for the determination of the oil content of oilseed-type hybrid sunflower seed. Eight sunflower seed samples of varying oil contents, replicated 5 times, were analyzed by the 3 procedures. The overall mean oil contents and standard deviations for the 8 samples were: AOCS method, 44.5% ± 0.33%; NMR, 44.8% ± 0.27%; and NIR, 44.2% ± 0.81%. Analysis of variance of the means of the 3 methods of analysis indicated no difference (p>0.05) in oil content due to the method. However, there was a difference (p>0.001) in total oil content due to replicated analyses of the same sample with the NIR method. With the AOCS and NMR methods, no effect (p>0.05) of replicated analyses of the same sample was found. The NMR method was more precise and repro-ducible than the other 2 methods. Although the NIR mean oil contents were not significantly different from the means of the other 2 methods, the coefficient of variations for all samples were consistently higher for the NIR analyses than for the AOCS and NMR analyses.     

A new catalyst for the selective hydrogenation of sunflower seed oil

A new Ni catalyst supported on sepiolite has been prepared by the precipitation/deposition method. Its activity and selectivity was tested in the hydrogenation reaction of sunflower seed oil. The variables studied were active phase concentration, reaction temperature and stirring speed. For contrasting purposes, a commercial catalyst designed for the same objective by Süd Chemie A.G. (Munich, Germany), G-53, was also tested under the same set of conditions. Selectivity to oleic acid with the new catalyst was appreciably better. The activation energies obtained with both catalyst were of the same order and within the range of those found in the literature for conventional nickel catalysts.     

Tocopherol oil concentration in field-grown sunflower is accounted for by oil weight per seed

Tocopherols are natural antioxidants that increase the stability of fat-containing foods and perform important biological activities. Significant variations (389 to 1873 μg g oil⁻¹) in the total tocopherol concentration of sunflower seed oil have been reported. The main objectives of this work were to determine the influence of intercepted photosynthetically active radiation on tocopherol concentration during seed filling and to establish and validate relationships between tocopherol concentration in oil and other quality variables of the seed. Seven sunflower hybrids were grown under good water and nutritional conditions in two similar experiments carried out in two contrasting environments. Treatments were applied to modify the amount of radiation intercepted per plant during seed filling in order to obtain a range in oil yield per plant and its components. Greater per plant intercepted radiation decreased the tocopherol concentration in oil. Tocopherol concentration decreased when oil weight per seed increased. Tocopherol concentration stabilized for oil weight per seed higher than 23 mg oil seed⁻¹. This exponential relationship accounted for 73% of the variability in tocopherol concentration (507 to 1203 μg g oil⁻¹) despite differences in hull type, locations, hybrids, and radiation treatments. The proposed relationship acceptably predicted independent results. Crop management techniques could lead to seeds with greater concentrations of tocopherols.     

环氧葵花籽油的合成及其在环氧树脂共混物中的应用研究

通过考察催化剂用量、反应温度及反应时间、氧化剂等因素对环氧葵花籽油产率的影响,确定了较适宜的反应条件.在此反应条件下产品产率大于90％.考察了环氧化葵花籽油含量对环氧树脂/环氧葵花籽油共混物冲击强度的影响.结果表明,当环氧化葵花籽油的质量分数为30％时,共混物的冲击强度比纯环氧树脂提高了60％.