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1.
H. Schiller 《European Journal of Lipid Science and Technology》1989,91(2):66-68
Fat Accompanying Components of the Oil of Sea Buckthorn The water steam distillate mainly contains esters of ethanol and of isoamylalcohol with fatty acids and benzoic acid as well as benzaldehyde and benzylalcohol. The composition of the shell waxes and the unsaponifiable of flesh oil and seed oil were determined. The unsaponifiable of the flesh oil consists of long chain epoxides, alcohols, sterols and triterpenes. The main component of the unsaponifiable of the seed oil is phytol. 相似文献
2.
Wax composition of sunflower seed oils 总被引:1,自引:3,他引:1
Amalia A. Carelli Lorna M. Frizzera Pedro R. Forbito Guillermo H. Crapiste 《Journal of the American Oil Chemists' Society》2002,79(8):763-768
Waxes are natural components of sunflower oils, consisting mainly of esters of FA with fatty alcohols, that are partially
removed in the winterization process during oil refining. The wax composition of sunflower seed as well as the influence of
processing on the oil wax concentration was studied using capillary GLC. Sunflower oils obtained by solvent extraction from
whole seed, dehulled seed, and seed hulls were analyzed and compared with commercial crude and refined oils. The main components
of crude sunflower oil waxes were esters having carbon atom numbers between 36 and 48, with a high concentration in the C40−C42 fraction. Extracted oils showed higher concentrations of waxes than those obtained by pressing, especially in the higher
M.W. fraction, but the wax content was not affected significantly by water degumming. The hull contribution to the sunflower
oil wax content was higher than 40 wt%, resulting in 75 wt % in the crystallized fraction. The oil wax content could be reduced
appreciably by hexane washing or partial dehulling of the seed. Waxes in dewaxed and refined sunflower oils were mainly constituted
by esters containing fewer than 42 carbon atoms, indicating that these were mostly soluble and remained in the oil after processing. 相似文献
3.
A chromatographic method is described to measure the crystallizable wax content of crude and refined sunflower oil. It can
also be applied to any other vegetable oil. The preparative liquid chromatography step on a glass column containing a silica
gel adsorbent superimposed upon a silver nitrate-impregnated silica gel support is used to isolate a wax fraction which is
then analyzed by gas chromatography. The recovered wax fraction contains, in addition to the crystallizable waxes, hydrocarbons
and other compounds with gas chromatographic retention times corresponding to waxes with chain lengths C34−C42. These compounds are short-chain saturated waxes in fruit oils, such as grapeseed and pomace. In seed oils such as sunflower,
soybean or peanut, the compounds initially referred to as “soluble esters” are identified as monounsaturated waxes, esters
of long-chain saturated fatty acids, and a monounsaturated alcohol, mainly eicosenoic alcohol. Such waxes are absent from
corn or rice bran oils. 相似文献
4.
The chemical composition and percentage of waxes in sunflower oil are presented in relation to the crude oil quality obtained
from decorticated or undecorticated sunflower seed. Three methods of winterizing are described: the conventional method with
separation by filters, crystallization with a wetting agent and separation by centrifuge and winterization in solvent. We
also comment on methods for checking the quality of winterized sunflower oil. 相似文献
5.
Thomas K. Miwa 《Journal of the American Oil Chemists' Society》1972,49(11):673-674
Compositions of synthetic liquid waxes derived from erucic-containing seed oils vary considerably. These differences, when
determined by gas chromatography, allow “fingerprint” identification of the source of oil.
ARS, USDA. 相似文献
6.
Limanathes douglasii seed oil glycerides contain fatty acids which predominantly (97%) have 20 or more carbon atoms. Fatty acids were prepared
by saponification; fatty alcohols, by sodium reduction of the glycerides; and liquid wax esters, byp-toluenesulfonic acid-catalyzed reaction of the fatty acids with the fatty alcohols. Solid waxes were prepared by hydrogenation
of the glyceride oil and of the wax esters. Chemical and physical constants were determined forLimnanthes douglasii seed oil and its derivatives. The liquid wax esters had properties very similar to those of jojoba (Simmondsia chinensis) seed oil. The solid hydrogenated wax ester was identical in physical appearance and melting point to hydrogenated jojoba
seed oil.
A laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, USDA. 相似文献
7.
Erica R. Baümler Guillermo H. Crapiste Amalia A. Carelli 《Journal of the American Oil Chemists' Society》2007,84(6):603-608
Wax distribution in sunflower seeds was determined by capillary-gas chromatography, as well as both the wax composition in
sunflower oils obtained from washed seeds and the wax composition in the solvent extracts. The dehulling efficiency was evaluated
by using a laboratory centrifugal process. The washing effect on hull morphology and on wax distribution was observed by scanning-electron
microscopy. Washing preferentially removed the crystallized fraction, hexane being the most effective solvent. Short contact
times (20 s) at 25–40 °C were sufficient to extract the insoluble waxes by hexane washing. The extracted material consisted
of C40–C54 waxes with higher percentages of extracted C44, C46 and C48. These are superficially in the hull of sunflower seed
presenting a non-uniform distribution as observed by microscopy. Solvent washing with pre-heating of the seeds caused a decrease
in sample moisture content, which reduced dehulling ability. Ethanol-washed seeds were the easiest to dehull, but higher production
of fines was also observed. Solvent washing improves both the dehulling-seed ability increment and the recovery of sunflower
waxes as a by-product for commercial use. 相似文献
8.
Michael Raß Christian Schein Bertrand Matthäus 《European Journal of Lipid Science and Technology》2008,110(7):618-624
Sunflower oil is the second most important virgin oil in Europe but, from the nutritional point of view, the assessment of this oil has become increasingly poorer over the last few years because of the high amount of linoleic acid in traditional sunflower seeds. Today sunflower oil with a high oleic acid content is coming more into the focus of interest since the fatty acid composition is more comparable to rapeseed and olive oil. Another important aspect is that the high content of oleic acid results in a high oxidative stability, making this oil interesting for a wide range of applications. A special challenge is the production of high‐quality tasty virgin sunflower oil because, in contrast to other raw materials, about 30% of sunflower seeds consist of hulls that are covered by waxes. During oil processing these waxes are co‐extracted with the oil, resulting in undesired turbidity of the oil on storage. Pressing of the raw material is done in a screw press or expeller and results in residue fat contents between 7 and 15% depending on the pressing conditions. We discuss two possibilities to avoid or to remove waxes by dehulling of the seeds or winterisation of the resulting oil. Dehulling is carried out by an impact dehuller with removal of the hulls by airflow and gravity. Removal of hulls before pressing improves the sensory quality of the oil because it results in products with a mild sunflower seed‐like nutty taste, while oils from whole seeds often have a woody and bitter taste. In addition, the development of heat during pressing is reduced if dehulled seeds are used for oil production. Conventional sunflower seeds are processed mainly in big oil mills, whereas in small and medium‐sized facilities organic raw material is in use. 相似文献
9.
J. R. Pritchard 《Journal of the American Oil Chemists' Society》1983,60(2):322-332
Current oilseed trade and trading specifications for soybeans, rapeseed, sunflower seed, palm kernels and copra are reviewed and compared with crude oil quality specifications, palm oil included. The limitations of the quality indices of the oilseeds are discussed with reference to present day needs of refiners producing end products of good quality, stability and yield. The developing, more stringent demands of physical refining on crude oil quality are outlined. The influence of seed quality, handling and the capability of the crusher to influence quality and yield with current technology is assessed. Particular reference is made to the degree of extraction, phosphatides, chlorophyll, waxes, free fatty acids and bleachability. Desirable attributes in specifications are listed and recommendations made which could benefit both processor and grower in the long term and facilitate international trade. 相似文献
10.
A rapid estimate of wax content in sunflower seed oil may be obtained by heating the oil to 130 C and subsequent cooling in ice for 10 to 15 min. Microcrystalline waxes are then formed. They are quantified by measuring increased turbidity with a sensitive turbidity meter. Calibration is made with thoroughly dewaxed oil to which known amounts of wax are added, and the turbidity increase is determined after 10 minutes at 0 C. The method has been compared with modified cold test, comprising visual inspection after 24 hours at 0 C and after 5 days at 20 C. The rapid tubidimetric method is superior to cold test in predicting the tendency of oils to precipitate small amounts of wax after long-time storage. 相似文献
11.
Amalia A. Carelli Erica B. Bäumler Liliana N. Ceci 《European Journal of Lipid Science and Technology》2012,114(11):1312-1319
In this work, a modified International Olive Council (IOC) method for wax determination involving a double‐adsorbent layer of silica gel and silver nitrate‐impregnated silica gel is presented (SN method). Column chromatography by the SN method did not show retention of wax esters standards with an even number of carbon atoms (C34–C44), observing recovery percentages higher than 90% even for unsaturated wax esters. All wax fractions were lower by the SN method than by the IOC method, resulting in a percentage decrease in the total wax content (olive oils: 20–50%, crude sunflower oil: 38%, crude soybean oil: 58% and crude grape seed oil: 13%). Olive oils analysed by the SN method showed increases of up to 27% in C40 relative percentage with respect to the IOC method. Additionally, decreases were observed by the SN method in the relative percentages for odd‐carbon atom waxes for the seed oils in comparison to the IOC method (crude sunflower oil: 27%, crude soybean oil: 28% and crude grape seed oil: 13%). The main advantages of the proposed modification consist in its easy implementation and a better determination of wax esters (C34–C60) by controlling their complete recovery and removing interfering substances. The method is suitable for quality control and for authentication of olive oil and seed oils as well as in processing monitoring. Practical applications: The proposed method is useful in the quality, authentication and processing control of fruit and seed oils. Moreover, it can be an important tool for vegetable oil industries to control the efficiency of the wax separation process to prevent turbidity in the refined oil. 相似文献
12.
Diego Canizares Paul Angers Cristina Ratti 《Journal of the American Oil Chemists' Society》2021,98(3):329-339
Valorization of the agri-food industry by-products could contribute to curb issues related to food security and environmental problems. Flax and wheat seeds are major products of this industry, but their production is associated with tons of straws that can be valorized for their cuticular and epicuticular waxes. We aimed to determine the organogelation capacity of epicuticular waxes in comparison to cuticular waxes from both flax and wheat straws. Epicuticular waxes from flax and wheat straws have structured canola oil at 2% and 4% (w/w), respectively, whereas cuticular waxes from flax and wheat straws required critical concentrations of 4% and 5% (w/w), respectively. Characterization of the organogelation capacity (onset of crystallization temperature, temperature of phase transition, crystal morphology, solid fat, crystalline structure, and oil binding capacity) was also carried out. The high onset of crystallization temperature (38.1 ± 1.2°C), the phase transition at high temperature (38 ± 1.5°C), and capacity to structure canola oil at low concentration showed that epicuticular wax from flax straw is a promisor fat substitute, presenting organogelation properties comparable to the best results obtained in the literature for other vegetal waxes. 相似文献
13.
Rapid determination of wax in sunflower seed oil 总被引:1,自引:0,他引:1
W. H. Morrison 《Journal of the American Oil Chemists' Society》1982,59(7):284-285
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 . 相似文献
14.
In the United States, sorghum is primarily used for animal feed and ethanol production but has potential to provide value-added coproducts including waxes and oil. The surface of sorghum contains 0.1–0.4% wax; however, wax extraction from whole kernels before fermentation may not be economical. An alternative method for this extraction could be facilitated through decortication, abrasion of the surface to remove bran. Decortication increases the starch content of decorticated sorghum, potentially improving ethanol yields, while concentrating wax and oil to the bran. Typically, oil (triacylglycerols) and waxes are extracted from bran in one extraction and waxes are precipitated from oil using cold temperatures then filtration. This research compared traditional fractionation (simulated with a two-step, single-temperature extraction) to a two-step, dual-temperature extraction, whereby oil is first extracted at room temperature and then waxes at elevated temperature. Extractions were performed using an accelerated solvent extractor with hexane or ethanol as solvents. Ethanol extraction showed greater yields (~15% w/w) compared to those of hexane (~11% w/w) because polar materials were extracted. Using hexane, the two-step, dual-temperature fractionation separated waxes from oils via the temperature of extraction solvent with similar purity to the traditional method that fractionated via cold precipitation and filtration. For ethanol, the traditional single-step method fractionated with higher wax purity but lower oil purity compared to the two-step, dual-temperature fractionation. 相似文献
15.
The mechanism of action of a commercial inhibitor on the crystallization of waxes present in sunflowerseed oil was analyzed.
The results showed the inhibitor favored nucleation, leading to a decrease in the amount of waxes available for the growth
of the crystals already formed. The inhibitor decreased the crystal size, increased the number of crystals and possibly caused
slower crystallization of waxes. 相似文献
16.
Samia Mezouari S. Parkash Kochhar Karin Schwarz Karl Eichner 《European Journal of Lipid Science and Technology》2006,108(8):679-686
The effect of dewaxing pretreatment on rice bran oil composition and stability was investigated, as well as the possibility to use rice bran oil waxes as natural antioxidants at high temperatures. A correlation between wax content and dewaxing time was noticed. The pre‐dewaxing process led to a loss of minor compounds, which negatively affected the oxidative stability index (OSI) of the dewaxed oil. The addition of rice bran oil waxes improved the oil stability index and heat stability of sunflower oil. An increase of 60% of the OSI and a significant decrease in polymer formation (59.2%) were observed. 相似文献
17.
E. C. Baker G. C. Mustakas V. E. Sohns 《Journal of the American Oil Chemists' Society》1977,54(10):387-391
Crambe seed was dehulled and screw pressed to remove approximately two-thirds of the oil, and then it was hexane-extracted
to remove the rest. The defatted meal was toasted in the presence of moisture to form a crisped meal possessing fast drainage
characteristics required for continuous filtration. The crisped meal was slurried with four parts of water, filtered, and
washed on a continuous pilot-plant filter. Water washing removed about one-fourth of the meal solids, which contained 92-96%
of the glucosinolates. Estimated processing costs for water-washing crambe meal are 22-23 dollars per ton of unwashed defatted
meal, in addition to the cost of crushing the seed to oil and meal.
Presented at the AOCS Meeting, Dallas, April 1975. 相似文献
18.
Jill K. Winkler-Moser Julie Anderson Jeffrey A. Byars Mukti Singh Hong-Sik Hwang 《Journal of the American Oil Chemists' Society》2019,96(11):1235-1248
Four natural waxes were evaluated as stabilizers in peanut butter. The potential advantage of using natural waxes would be the replacement of current stabilizers such as hydrogenated or tropical oils, thereby reducing saturated fats and satisfying clean label requirements. Beeswax (BW), candelilla wax (CLW), rice bran wax (RBW), sunflower wax (SFW), and a commercial peanut butter stabilizer, hydrogenated cottonseed oil (HCO), were added to three natural peanut butter brands at levels ranging from 0.5% to 2.0% (w/w) and tested for accelerated oil release, long-term stability, firmness, and rheology. At levels ≥0.5%, all waxes improved oil-binding capacity (OBC). SFW and HCO had the highest OBC, followed by RBW, CLW, and BW. All waxes reduced the amount of oil separation after 6 months at 22 ± 2 °C. HCO followed by SFW reduced oil separation the most, but there were no significant differences between stabilizers at 1–2%. Firmness and yield stress increased with increasing stabilizer level, with SFW increasing firmness the most, followed by HCO, RBW, and CLW, while BW had the lowest effect. The results indicate that the waxes may be feasible replacements for hydrogenated oils as peanut butter stabilizers, but levels would need to be optimized depending on the product characteristics and wax type. 相似文献
19.
María E. Carrín Amalia A. Carelli 《European Journal of Lipid Science and Technology》2010,112(7):697-707
The major fatty acids of peanut oil acylglycerols are palmitic (C16:0), oleic (C18:1), and linoleic (C18:2) acids, and only a trace amount of linolenic fatty acid (C18:3) is present. Thus they have a very convenient oxidative stability and have been considered premium cooking and frying oils. This paper provides information about compositional data of peanut oil taking into account major (triacylglycerols and their fatty acids) and minor (free fatty acids, diacylglycerols, phospholipids, sterols, tocopherols, tocotrienols, triterpenic and aliphatic alcohols, waxes, pigments, phenolic compounds, volatiles, and metals) compounds. Moreover, the influence of genotype, seed maturity, climatic conditions, and growth location on peanut oil chemical composition is considered in the present report. In addition, peanut oils from wild species found in South America as well as from peanut lines developed through conventional breeding are also compared. 相似文献
20.
Silvana Martini María Cristina An 《European Journal of Lipid Science and Technology》2005,107(2):74-79
Storage conditions of oil seeds before industrial extraction might influence the quality of the crude oil. The objective of this work was to study the influence of sunflower seed storage conditions (temperature and time) on the quality of the resulting oil in terms of its wax content and composition. Sunflower seeds were stored under different conditions, 10, 21 and 37 °C, in sealed recipients. Extractions of the seeds with hexane were made to obtain the oil at different storage times. The amount of oil extracted (25–40%) showed no significant differences with storage conditions. Wax content of the samples was determined with two different methods (laser polarized turbidimetry and microscopy), and results showed that wax concentration increased with storage conditions (time and temperature). Composition of wax components, determined using capillary gas chromatography, during storage was approximately constant for C35–C39 and showed significant differences for C40–C48 components. Waxes with high carbon number cause more turbidity than waxes with low carbon number, due to their higher melting point, resulting in a low‐quality crude oil and therefore in variations in processing conditions during the oil refining. According to the data showed in this study, seed storage at low temperatures during short periods of time may be the more adequate conditions to obtain high‐quality oil. 相似文献