共查询到20条相似文献,搜索用时 31 毫秒
1.
Ayhan Baştürk Şebnem Badem M. Murat Ceylan 《European Journal of Lipid Science and Technology》2023,125(9):2200213
In this study, safflower oil oleogels were made using propolis wax and carnauba wax in three different concentrations each, and their effectiveness as a fat substitute in cake was evaluated afterward. Oleogels' oxidative stability and characterization were looked into. In oleogels, the oil binding capacity, solid fat content, and crystallization time were all assessed. The cakes underwent an examination for moisture content, texture, and sensory evaluation. Additionally, analyses of fatty acid composition, free fatty acidity, oxidative stability (peroxide value, conjugated diene-triene), 3-monochloropropane-1,2-diol (3-MCPD), and glycidyl were carried out both before and after baking in oleogels and shortening. Several of the physical, textural, and sensory qualities of the oleogel-based cakes were acceptable when compared to those of the shortening-based cakes. The general acceptability of cakes made with carnauba wax was very high and almost under control. The acceptability of cakes made with propolis wax oleogels was lower than this. The study of these criteria has shown that safflower oil-based carnauba and propolis wax oleogels can be utilized to produce high-quality, healthful cakes with a high amount of unsaturated fatty acids. Practical Applications : To replace fat phases in cake products high in saturated fatty acids and to enhance the fatty acid profile of the cakes, safflower oil-based oleogels with propolis wax and carnauba wax are a very good option. The results obtained provide useful information for the production of high-quality cakes with higher unsaturated fatty acid content, recommended for a healthier diet, with these oleogels containing different concentrations of oleogelator. 相似文献
2.
Type 1 yellow carnauba wax has been separated into its structural constituents. Analyses of these constituents by a variety
of conventional techniques has shown the composition to be: hydrocarbon 0.3–1%, aliphatic esters 38–40%, monohydric alcohols
10–12%, ω-hydroxy aliphatic esters 12–14%,p-methoxycinnamie aliphatic diesters 5–7%,p-hydroxycinnamic aliphatic diesters 20–23%, an uncombined triterpene type diol 0.4% and uncombined acids and other unknown
constituents 5–7%. Type 4 carnauba wax, the common wax of commerce, was found to be essentially the same as Type 1, with the
exception that for Type 4, the cinnamic esters were highly polymerized and none of the uncombined triterpene diol could be
isolated.
Presented at the AOCS Meeting, New Orleans, April 1970. 相似文献
3.
Summary 1. The ethyl esters of the acids of carnauba wax were fractionally distilled at 0.3 mm.
2. Approximately 32% of the wax acids are n-aliphatic acids. Evidence was found which indicated the presence of all the even
carbon acids from C18 to C30.
3. The remaining 68% of the acids are unidentified, but the greater part of them are different in nature from n-aliphatic
acids.
4. Tetracosanoic acid, the most abundant of its n-aliphatic acids, has been isolated from the wax for the first time in a
degree of purity exceeding 95%.
Submitted in partial fulfillment of the degree of doctor of philosophy, the Graduate School. 相似文献
4.
Summary and Conclusions 1. Fractional crystallization alone is not an adequate method for isolating pure alcohols from carnauba wax.
2. More than 50 per cent of the alcohols of carnauba wax can be distilled at 0.5 mm. pressure without serious decomposition.
3. Fractional distillation of the free wax alcohols at 0.5 mm. is a useful method of separating these compounds, but recrystallization
of the resulting fractions is necessary.
4. There are substances in the unsaponifiable portion of carnauba wax which are of an unknown nature but which are probably
not n-aliphatic alcohols.
5. For the first time, three alcohols, octacosanol (C28), triacontanol (C30), and dotriacontanol (C32) have been isolated from carnauba wax in states of purity of 95 per cent or better.
6. Dotriacontanol is even more abundant in the wax than is triacontanol.
Submitted in partial fulfillment of the degree of Doctor of Philosophy, the Graduate School. 相似文献
5.
An investigation of rice bran oil tank settling 总被引:2,自引:2,他引:0
A wax-like settling is observed in tanks in which rice bran oil is stored. “Soft” and “hard” wax fractions have been isolated
from this settling by solvent Crystallization. Previous investigation has shown that the settling consists mainly of wax esters
of long chain alcohols and long chain fatty acids. The present work describes the column chromatographic analysis of unhydrolyzed
tank settling. The presence of an aromatic moiety is indicated in the infra red spectrum. Comparison of data obtained by analysis
of the tank settling before and after hydrolysis shows that it contains only 33% of monomeric esters; the remainder may be
present as a polymeric ester, as found in carnauba wax. Investigation of different samples of rice bran oil has shown that
the ratio of monomeric to polymeric fraction varies with the history of the bran. 相似文献
6.
Keum T. Hwang Susan L. Cuppett Curtis L. Weller Milford A. Hanna 《Journal of the American Oil Chemists' Society》2002,79(6):521-527
Grain sorghum wax has been judged to be a potential source of natural wax with properties similar to carnauba wax. Approximately
0.16–0.3% (w/w) wax can be extracted from grain sorghum depending on the efficiency of the organic solvents. Although the
melting points of carnauba wax and sorghum wax are similar, i.e., 78–86 and 77–85°C, respectively, they differ in acid values,
i.e., 2–10 and 10–16, respectively, and saponification numbers, i.e., 77–95 and 16–49, respectively. Improved knowledge of
the properties, composition, and analysis of grain sorghum wax would assist in efforts for industrial application of this
product. Major components of sorghum wax are hydrocarbons, wax esters, aldehydes, free fatty alcohols, and FFA. The hydrocarbons
consist mainly of C27 and C29, and the aldehydes, alcohols, and acids are mainly C28 and C30. The wax esters are mostly esters of C28 and C30 alcohols and acids. 相似文献
7.
Summary Diglycerides of the fat-forming acids yield, on esterification with succinic, adipie, and other shortchain dibasic acids,
a poteutially useful series of compounds ranging from hard, high-melting waxes to viscous oils which will not crystallize.
A number of the properties of these compounds were determined in carlier investigations.
In the present investigation additional properties of the 1,3-diolein and 1,3-distearin esters of succinic and adipic acids
were determined. Surface and interfacial tensions were measured and found to be similar to those of cottonseed oil. The smoke
points also were found to be similar to that of cottonseed oil. The ability of the compounds to thicken cottouseed oil was
measured and found to be somewhat better than that of highly hydrogenated cottonseed oil at levels above about 12%, and the
mixtures were relatively resistant to fat leakage. In hardness the distearin esters of succinic and adipic acid were comparable
to carnauba wax and were over twice as hard as highly hydrogenated cottonseed oil. Permeability to water vapor was found to
be greater than that of highly hydrogenated cottonseed oil and carnauba wax and about equal to that of cocoa butter.
Presented at the 33rd Fall Meeting, American Oil Chemists' Society, Los Angeles, Calif., September 28–30, 1959.
One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S.
Department of Agriculture. 相似文献
8.
Allan N. de S. Dantas Ticiane A. Magalhães Wladiana O. Matos Sandro T. Gouveia Gisele S. Lopes 《Journal of the American Oil Chemists' Society》2013,90(10):1475-1483
In this work the analysis of inorganic elements (Al, Ca, Cu, Fe, K, Mg, Mn, Na and Zn) in different types of carnauba waxes (types 1, 3 and 4) was implemented. The Box‐Behnken experimental design was used to optimize the digestion of the carnauba wax sample using a microwave‐assisted approach. The following parameters were evaluated: microwave power applied (600–1,000 W), time of microwave power application (5–20 min) and nitric acid volume (1–4 mL). The residual carbon content (%RCC) was measured by ICP OES (inductively coupled plasma optical emission spectrometry) to evaluate the efficiency of the digestion. The %RCC values in all of the experiments were below 16 %. The best conditions for carnauba wax digestion were found: 800 W applied power for 15 min using 2.5 mL of HNO3. In these conditions the %RCC was lower than 4 %. The amounts of Al, Ca, Cu, Fe, K, Mg, Mn, Na and Zn in these samples were determined by ICP OES. The average contents of Al, Ca, Fe and K found in the carnauba wax type 1 were 28.6 ± 1.5, 33.8 ± 2.8, 18.5 ± 1.1 and 37.2 ± 2.5 mg kg?1, respectively. For carnauba wax types 3 and 4 larger amounts were found. The principal components analysis (PCA) showed three groups of carnauba wax with the first two principal components. 相似文献
9.
Summary Sorghum grain was found to contain approximately 50 times more wax and two-thirds as much oil as corn. The wax, which had
properties similar to carnauba wax, could be removed by extracting the unground grain with hot solvent.
Sorghum grain oil was found to be similar to corn oil in composition. Sorghum grain oil had the following characteristics:
unsaponifiable matter 1.88%, acid value 3.14, saponification value 181, iodine value 119.0, thiocyanogen value 76.7, acetyl
value 16.7, and a refractive index of 1.4718 at 25°C. The mixed fatty acids from the oil contained 36.2% oleic, 49.4% linoleic,
8.3% palmitic, 5.8% stearic, 0.2% myristic, and 1% hexadecenoic acid.
Financial support for this work was furnished by The Kansas Industrial Development Commission
Contribution No. 308 from The Department of Chemistry. 相似文献
10.
Robert A. Moreau Megan E. Sharma Alberto Nuñez Charles A. Mullen Michael J. Powell Kerby Jones Andrew Harron Jeffrey T. Cafmeyer 《Journal of the American Oil Chemists' Society》2020,97(12):1299-1308
Sorghum wax can be extracted from the surface of sorghum (Sorghum bicolor) kernels. It is composed mostly of a mixture of unsaturated C28 and C30 alkanes, fatty acids, fatty alcohols, and fatty aldehydes. Like carnauba wax, sorghum wax is a hard wax with a high melting point and it has potential edible and industrial applications. The yield of sorghum wax from the surface of sorghum kernels is 0.2–0.5 g of wax per 100 g of kernels. Sorghum wax can also be recovered from the “distillers oil” which is obtained after fermentation of sorghum (milo) or sorghum/corn blends in dry grind fuel ethanol plants. This distillers sorghum wax can potentially be obtained in yields of up to 10% by chilling the distillers oil to precipitate the wax and then recovering it via centrifugation or filtration. Like sorghum kernel wax, distillers sorghum wax is mainly composed of C28 and C30 alkanes, alcohols, and aldehydes in the molecular weight (MW) range of 350–450. However, we found that 7–49% w/w of distillers sorghum wax is composed of larger wax components with MW of 799–912. Analysis via high-resolution atmospheric pressure chemical ionization mass spectrometry (APCI) and gas chromatography with electron ionization mass spectrometry (GC/MS-EI) resulted in exact mass data and fragmentation patterns that suggested that these high MW compounds are monounsaturated fatty aldehyde dimers, likely formed by aldol condensation. Further confirmation supporting the GC/MS data for the aldol reaction was obtained by comparison with similar aldol products. 相似文献
11.
Summary The proportion of normal acids among the acids of carnauba wax has been found, by a chromatographic separation method, to
be 38%. The normal acid mixture has been separated into its components by amplified distillation of the methyl esters, which
revealed the presence of the acids of even carbon number from C18 to C30. The acids were identified by their melting points, long crystal spacings, and crystal habit. An estimate of their relative
amounts is as follows: C18, 3%; C20, 11.5%; C22, 9%; C24, 30%; C26, 12%; C28, 16.5%; C30, 7%.
Part V of this series: The Aliphatic Alcohols of Wool Wax, by K. E. Murray and R. Schoenfeld, J. Am. Oil Chem. Soc.,29; 416–420 (1952). 相似文献
12.
Juan J. Jiménez José L. Bernal Maria J. del Nozal Maria T. Martín Laura Toribio 《European Journal of Lipid Science and Technology》2009,111(9):902-911
The minimum percentages of adulteration of pure beeswax from Apis mellifera with three paraffins of different melting points and with cow tallow, stearic acid and carnauba wax that can be detected by gas chromatography with flame ionization detection were established. The concentrations of 93 endogenous beeswax compounds such as aliphatic hydrocarbons, olefins, acids, monoesters, alcohols and hydroxyacids were measured in relation to an internal standard (octadecyl octadecanoate) in mixtures of beeswax with the six adulterants; the variation of the concentrations of the compounds with the adulteration percentage was also studied. Percentages higher than 1–4% of each adulterant can be detected in the mixtures. The added adulterant can be identified by the non‐endogenous beeswax compounds observed in the chromatogram; the changes in the concentrations of some beeswax compounds are also useful to corroborate the identification. 相似文献
13.
Thomas K. Miwa 《Journal of the American Oil Chemists' Society》1971,48(6):259-264
HCl-catalyzed ethanolysis followed by saponification readily surmounts the resistance of long chain wax esters to direct hydrolysis
by alkali. Additionally, choosing ethyl instead of methyl esters allows baseline separations between long-chain alcohols and
corresponding esters in gas liquid chromatographic (GLC) analysis of total alcohol and acid components before saponification.
Liquid wax esters were analyzed on a temperature-programmed 3% OV-1 silicone column. Geographical and genetic effects on the
variability of jojoba oil composition were investigated with five different seed samples. Major constituents in jojoba seed
oil from shrubs in the Arizona deserts, as indicated by GLC analyses of oil, ethanolysis product, isolated fatty alcohols
and methyl esters of isolated fatty acids, were C40 wax ester 30%, C42 wax ester 50% and C44 wax ester 10%; octadecenoic acid 6%; eicosenoic acid 35%, docosenoic acid 7%, eicosenol 22%, docosenol 21% and tetracosenol
4%. Oil from smaller leaved prostrate plants growing along California’s oceanside showed a slight tendency toward higher molecular
size than oils from the California desert and Arizona specimens. The wax esters are made up of a dispro-portionately large
amount of docosenyl eicosenoate and are not a random combination of constituent acids and alcohols.Lunaria annua synthetic wax ester oil was used as a model for evaluating the analytical procedures.
Presented at the AOCS Meeting, Chicago, September 1970
No. Utiliz, Res. Dev. Div., ARS, USDA. 相似文献
14.
The wax material in the secretion of a scale insect,Ceroplastes pseudoceriferus Green was analyzed chemically with special interest to the composition of higher fatty acids and higher alcohols. The wax
consists of 34.2% fatty acids, 27.1% unsaponifiable matter and 29.5% resin acids. The fatty acids were found to be a complex
mixture of 15 normal acids ranging from C8 to C32. Of these, octacosanoic, triacontanoic and dotriacontanoic acids comprise over 30% of the wax. Presence of relatively large
amount of unsaturated fatty acids of the C18 series (2.8% of the wax) is of particular interest.
From the unsaponifiable fraction, only one saturated straight chain aleohol, bexacosanol, was detected (2.7% of the original
wax). The other unsaponifiable matter was considered to be cyclic or branched carbon chain, and consisted of at least 12 to
20 compounds. The resin acid fraction was also found to be a complex mixture of at least 13 to 14 components. 相似文献
15.
Thainá Araújo de Oliveira Islaine de Oliveira Mota Francisco Edinaldo Pinto Mousinho Renata Barbosa Laura Hecker de Carvalho Tatianny Soares Alves 《应用聚合物科学杂志》2019,136(47):48240
Plastic mulching for agricultural purposes is a technique which began in the last century and since then its use has been perfected. The fragments of some large-scale mulch films used may accumulate in the soil, release toxic substances, and affect soil microbial activity. The environmental problems generated by fragments of plastic films accumulated in soil have prompted the development and large-scale use of biodegradable plastic mulch films. The aim of this work is to develop biodegradable plastic mulch films from poly(butylene adipate co-terephthalate (PBAT), sugarcane residue, and carnauba wax and to evaluate its biodegradation when buried in soil. The films, obtained by flat extrusion, contained 2.5 and 5.0% sugarcane residue and 0 and 2.0% carnauba wax. Their biodegradation after burial in soil was monitored by mass loss, visual inspection, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Our data show biodegradation in soil to increase with sugarcane residue content and to be independent on carnauba wax addition. This behavior, confirmed by visual inspection, FTIR and SEM images, was associated with the biodegradability of lignocellulosic residues as microorganisms tend to attack this component first, thus eroding fiber/matrix interface and facilitating bio disintegration. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48240. 相似文献
16.
Enhancing the Efficiency and Regioselectivity of P450 Oxidation Catalysts by Unnatural Amino Acid Mutagenesis
下载免费PDF全文
![点击此处可从《Chembiochem : a European journal of chemical biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Joshua N. Kolev Jacqueline M. Zaengle Rajesh Ravikumar Prof. Rudi Fasan 《Chembiochem : a European journal of chemical biology》2014,15(7):1001-1010
The development of effective strategies for modulating the reactivity and selectivity of cytochrome P450 enzymes represents a key step toward expediting the use of these biocatalysts for synthetic applications. We have investigated the potential of unnatural amino acid mutagenesis to aid efforts in this direction. Four unnatural amino acids with diverse aromatic side chains were incorporated at 11 active‐site positions of a substrate‐promiscuous CYP102A1 variant. The resulting “uP450s” were then tested for their catalytic activity and regioselectivity in the oxidation of two representative substrates: a small‐molecule drug and a natural product. Large shifts in regioselectivity resulted from these single mutations, and in particular, for para‐acetyl‐Phe substitutions at positions close to the heme cofactor. Screening this mini library of uP450s enabled us to identify P450 catalysts for the selective hydroxylation of four aliphatic positions in the target substrates, including a C(sp3)?H site not oxidized by the parent enzyme. Furthermore, we discovered a general activity‐enhancing effect of active‐site substitutions involving the unnatural amino acid para‐amino‐Phe, which resulted in P450 catalysts capable of supporting the highest total turnover number reported to date on a complex molecule (34 650). The functional changes induced by the unnatural amino acids could not be reproduced by any of the 20 natural amino acids. This study thus demonstrates that unnatural amino acid mutagenesis constitutes a promising new strategy for improving the catalytic activity and regioselectivity of P450 oxidation catalysts. 相似文献
17.
Waxes Having High Dispersibility and Special Consideration of Their Suitability in the Manufacture of Colouring Masses for Carbon Paper Increasing amounts of waxes having fundamentally different chemical composition are being used as dispersion aids. In the manufacture of colouring masses for carbon papers, the materials used as vehicle of the colour and as dispersing agent for carbon black are hydrocarbons, wax acids and their natural esters. Whereas low-priced paraffins are mainly used for cheap carbon papers meant for a single use, carnauba wax is used for better quality carbon papers which can be used several times. The latter wax is especially suited because of its carbon black-dispersing and oil-binding properties. Since crude montana wax does not have these properties to such an extent as the carnauba wax, it was attempted to improve the carbon black-dispersing and oil-binding of montana wax by chemical synthesis. This was achieved by reacting crude montana wax with maleic anhydride and subsequent esterification of the reaction products with glycols. The results were successfully applied to the solution of problems involving dispersion of pigments and plastic additives. 相似文献
18.
Summary Methods for the determination of acid, ester, hydroxyl, and ketone (or aldehyde) groups and of mean molecular weights of small
samples of natural waxes are reported. Complete analyses can be made on 0.5 g. of sample. A simplified procedure for quantitative
separation of acid and unsaponifiable fractions of a wax is also reported.
Molecular distillations of beeswax, caranda wax, crude and refined candelilla wax, and ouricury wax, have fractionated these
complex mixtures into simpler ones. Hydrocarbons and free unsubstituted alcohols and acids, if present, distil readily at
150°C. A pot still suitable for convenient molecular distillation of up to 100-g. charges of waxes or other high melting materials
is described.
A method for the calculation of composition of unhydrolyzed waxes based upon function group analysis of molecular distillation
fractions is described. Results of application of this method to the waxes distilled are reported and show the ubiquitousness
of hydroxy acids. All of the above waxes and carnauba wax contain major proportions of esters of the hydroxy acids, and none
contains as much as one-half simple esters of unsubstituted acids and alcohols.
A portion of a dissertation submitted by Thomas Wagner Findley to the Graduate School of the Ohio State University in partial
fulfilment of the requirements for the Ph.D. degree.
S. C. Johnson and Son Inc. Fellow in Physiological Chemistry, 1946-50. 相似文献
19.
研究加工助剂AC-617A(聚乙烯蜡),RL22(脂肪酸酯类润滑油)和巴西棕榈蜡对氟橡胶性能的影响。结果表明:3种加工助剂均可以提高氟橡胶胶料的流动性,改善胶料的加工性能,提高填料在氟橡胶中的分散性,其中巴西棕榈蜡对胶料流动性的改善效果优于加工助剂AC-617A和RL22,而加工助剂RL22和巴西棕榈蜡对填料在氟橡胶中的分散性的改善效果更显著;加工助剂AC-617A和巴西棕榈蜡对硫化胶物理性能和耐热空气老化性能的影响较小,加工助剂RL22对硫化胶的压缩永久变形影响稍大;加工助剂在氟橡胶中的建议用量为1份以下。 相似文献
20.
Evaluating the Oil‐Gelling Properties of Natural Waxes in Rice Bran Oil: Rheological,Thermal, and Microstructural Study
下载免费PDF全文
![点击此处可从《Journal of the American Oil Chemists](/ch/ext_images/free.gif)
Chi Diem Doan Davy Van de Walle Koen Dewettinck Ashok R. Patel 《Journal of the American Oil Chemists' Society》2015,92(6):801-811
The main objective of this research was to enhance the understanding of the oil‐structuring properties of natural waxes. A number of natural food‐grade waxes were evaluated for their oil‐gelling properties using a combination of techniques, including rheology, differential scanning calorimetry, and polarized light microscopy. Based on the rheological measurements (oscillatory, flow, and thixotropic behavior), we found that rice bran wax, carnauba Brazilian wax and fruit wax showed weak gelling behavior in rice bran oil (prepared at concentrations as high as 5 % w/w), exhibiting relative low elastic moduli that displayed a high frequency dependency. On the contrary, carnauba wild wax, berry wax, candelilla wax, beeswax, and sunflower wax were efficient oleogelators forming strong gels at concentration of <2 % w/w. We attempt to explain these observed differences in gelling behavior by crystal morphology, network formation, and the final amount of crystalline phase. 相似文献