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1.
H. Wessels 《European Journal of Lipid Science and Technology》1976,78(6):250-252
Further Development of Codex Alimentarius Standards for Oils and Fats The present status of Codex Alimentarius Standards for oils and fats is reviewed. Further development of these standards is reported, based on discussions at the 8th meeting of the codex committee for oils and fats in London. The discussions concerned standards for low-erucic rapeseed oil, low-fat spreads, coconut-, palm-, palm kernel-, babassu-, grape seed- and marine oils as well as issues involving the range of application, fatty acid composition of individual oils and fats and use of solvents in the recovery and processing of fats. 相似文献
2.
H. Wessels 《European Journal of Lipid Science and Technology》1975,77(1):23-25
Further Development of Codex Alimentarius Standards for Oils and Fats Further development of Codex Alimentarius standards for oils and fats, which was discussed at the 7th meeting of the Codex Committee in London, is reported. Limits of fatty acid composition of individual oils and fats, problems of solvent residues as well as the development of new standards for lowerucic rapeseed oil, low calorie spreads, coconut oil, palm oil and palm kernel oil were discussed at the above meeting. It has already been realized that the Recommended Standards have a significant impact both on harmonization work within the European Community and international development of food legislation. 相似文献
3.
H. Wessels 《European Journal of Lipid Science and Technology》1978,80(5):198-200
Further Development of Codex Alimentarius Standards for Oils and Fats A report is given on the further development of Codex Alimentarius Standards for oils and fats, which was discussed in the 9th meeting of the Codex Committee on Fats and Oils from 28th November to 2nd December 1977 in London. Topics discussed were a collaborative report by FAO and WHO on the role of fats in human nutrition, the general standard for oils and fats, and standards for reduced fat margarine, low erucic acid rapeseed oil, coconut oil, palm oil, palm kernel oil, babassu oil, grape seed oil as well as marine oils. Furthermore, the limits of fatty acid composition as criteria for identification of specific oils and fats were discussed. 相似文献
4.
L. Masson 《Journal of the American Oil Chemists' Society》1981,58(3):249-255
The dietary and nutritional role of fats and oils is quite complex, as evident in the new biological findings about some of
their components that are essential to man. Fats and oils must be considered for both their quantitative and qualitative aspects,
their fatty acid compositions and relationships with average diets in different countries should be emphasized. Because of
some adverse physiological effects ascribed to saturated fatty acids, a tendency to increase the intake of polyunsaturated
vegetable oils has occurred to provide a good source of essential fatty acids, mainly linoleic acid. However, saturated fats
still are an important part of the diet in developed countries, especially “invisible” fats. Research must continue that is
related to modifications fats and oils undergo during industrial processes which affect their nutritional value. Compositions
of many fats and oils are provided. 相似文献
5.
Porcine pancreatic lipase hydrolysis and Jensen’s cooling curve methods can be adopted for detecting interesterified fat products
in a mixture with hydrogenated fats. Lipolysis of interesterified fats shows a relatively greater amount of saturated fatty
acids in the 2-monoglycerides in comparison with hydrogenated fats. A similar trend of the distribution pattern of fatty acids
also can be noted in a mixture. Interesterified fats do not show any rise in temperature in Jensen’s cooling curve experiment,
whereas hydrogenated fats show a distinct rise in temperature. A gradual increase in temperature is obtained for an interesterified
fat when it is mixed with increasing content of a hydrogenated fat. On the other hand, hydrogenated fat shows a lowering in
the rise of temperature when it is mixed with an interesterified fat. Simultaneous determination of the fatty acid profiles
of the 2-monoglycerides and Jensen’s cooling curve characteritics can be utilized in detecting the occurrence of one modified
fat in another. 相似文献
6.
Summary The oils from yellow mustard seed (Brassica alba), black mustard seed (Brassica nigra) of Indian origin, and rapeseed (Brassica Compestris) of unknown origin have been analyzed for their fatty acid composition without preliminary resolution of fatty acids by lead-salt-alcohol
or fractional crystallization methods. The results compare very favorably with those determined by other recently developed
methods. It may be concluded therefore that this method can be favorably employed for the determination of fatty acid composition
of fats containing higher unsaturated acids.
Confirmatory evidence has been obtained for the presence of eicosenoic acid in rapeseed oil.
The nature and amount of fatty acids of yellow mustard seed oil of Indian origin do not differ in any significant manner from
those of other cruciferous seed oils.
The present analysis of black mustard seed oil reveals a higher amount of linolenic acid, and the presence of a C20 monoethenoid acid, not heretofore reported.
Contribution No. 708 from the Department of Chemistry, University of Pittsburgh.
Presented in part at the Spring meeting of the American Oil Chemists’ Society, held in New Orleans, La., May, 1948.
Baliga and Hilditch’s paper. “The Component Acids of Rapeseed Oil” (J. Soc. Chem. Ind.67, 258–262 (1948). 相似文献
7.
F. R. van de Voort J. Sedman G. Emo A. A. Ismail 《Journal of the American Oil Chemists' Society》1992,69(11):1118-1123
A simple, rapid and reproducible method of determining the iodine value (IV) and saponification number (SN) for fats and oils
was developed with an attenuated total reflectance/Fourier transform infrared spectrometer and commercially available triglycerides
as calibration standards. Partial least squares was used to determine the spectral regions correlating with the known chemical
IV and SN values, and the calibration set was augmented with additional standards generated by spectral co-adding techniques.
The calibration model obtained was used to analyze commercially available fats and oils with a wide range of IV and SN values,
and the results were compared to the values obtained by American Oil Chemists’ Society methods. With the spectrometer calibrated
and programmed, IV and SN results could be obtained within 2–3 min per sample, a major improvement over conventional wet chemical
methods. 相似文献
8.
Daniel Melnick Frederick H. Luckmann Chester M. Gooding 《Journal of the American Oil Chemists' Society》1958,35(6):271-277
Summary The oils in use on a continuing commercial basis in the production of potato chips on a nation-wide scale are found to be
free of thermal polymers. This conclusion is supported by the similarity in physical properties and in chemical composition
between the fresh and heated oil in any one operation. In a) degree of unsaturation of oils, b) melting point, c) setting
point, d) fatty acid composition, e) free fatty acid content, f) concentration of fatty acid isomers, g)solids content index,
and h) in the crystallizing properties of the oils, there are no differences between fresh and heated oil of such magnitude
to warrant criticisms of the wholesomeness of the oil being absorbed by the chip.
The constancy in composition between heated and fresh oil, particularly with respect to the essential fatty acid content,
which is largely responsible for the noncaloric functions of fats in the diet (19), permits the same conclusions to be made
in regard to the nutritive value of the heated oils,i.e., of the triglycerides contained therein, as have been drawn from studies conducted on the corresponding fresh oils.
Based upon statistical quality control considerations, the oils employed in the survey of the potato chip industry have been
characterized by having a free fatty acid value of no greater than 0.60% and a decrease in iodine value of no greater than
3.0% in 95% of the operations. These control limits characterize the oils, which, on test, have led to the generalization
about the absence of thermal polymers in commercial potato chip frying oils.
Much of the material in this paper and in one recently published (1) was presented at the 48th Annual Meeting of the American
Oil Chemists' Society in the Symposium on “Fats in Nutrition and Health,” New Orlens, La., April 30, 1957. 相似文献
9.
F. V. K. Young 《Journal of the American Oil Chemists' Society》1985,62(2):372-376
The requirement for interchangeability of fats and oils is a result of such factors as availability and cost of raw materials,
and the effects of legislation or market preference on product composition. Such changes should not affect the product’s quality
or performance. Interchangeability is practiced today in the production of products for human food, animal feed and technical
uses, and is frequently controlled by computer.
It is necessary fully to identify a product and its essential features whether simply by melting point or a full triglyceride
structure. Modern analytical techniques such as NMR, GC, HPLC and DSC have enabled this identification to become a more exact
science.
The interchange may consist of a simple substitution of one oil or fat for another, or it may be more complex, involving a
number of oils and fats and processes. Finally, the nature of the product may be such that it has to be “tailor-made” using
sophisticated processes to produce the required triglyceride composition. The unit processes which are employed are blending,
hydrogenation, fractionation and interesterification. In the last process the recently published use of enzymes is of particular
interest.
Problems encountered are mainly concerned with the polymorphism of fats and oils which frequently sets limits on the proportion
of a particular fat which can be used. Limits are also imposed by plant processing capacity.
Palm and lauric acid oils are particularly important in the context of interchangeability for both edible and technical purposes
because of their fatty acid and triglyceride compositions. They provide good examples of usefulness, problems resulting from
polymorphism and the difficulties of substitution. 相似文献
10.
N. Gámez-Meza I. Higuera-Ciapara A. M. Calderon de la Barca L. Vázquez-Moreno J. Noriega-Rodríguez O. Angulo-Guerrero 《Lipids》1999,34(6):639-642
One of the few sources of long-chain n-3 polyun-saturated fatty acids is fish oil’ but considerable variation may exist according
to species and season. In this study’ the fatty acid profiles of sardine oils from Sardinops sagax caeruleus of the Gulf of California’ Mexico’ were evaluated in three seasonal catch periods. Oil quality was also evaluated by peroxide
and free acid values. The most abundant fatty acids found in the oils were palmitic acid (19.3%)’ oleic acid (14.3%)’ eicosapentaenoic
acid (EPA’ 20.4%)’ and docosahexaenoic acid (DHA’ 12.2%). There was no significant difference in the composition and quality
among the six reduction plants where the samples were obtained. However’ a significant difference in the proportion of EPA
and DHA in one of the catch seasons analyzed was observed. 相似文献
11.
H. Wessels 《European Journal of Lipid Science and Technology》1971,73(5):293-300
Codex Alimentarius Standards for Fats and Oils I A short introduction on the principles of Codex Alimentarius is given, which is being developed jointly by Food and Agricultural Organization (FAO) and World Health Organization (WHO) under participation of 75 member states. In the meanwhile Recommended Standards for fats and oils have been laid down. They will be forwarded to governments for acceptance or rejection. Development of these standards is reported here and the most significant regulations are discussed. Some important Recommended Standards are presented in appendix in their English version. 相似文献
12.
While practically all the fatty acids produced in the fatty acid industry are distilled products, these materials are all,
at least to some degree, fractionated fatty acids. Rarely indeed are today’s fatty acids suited for any of the many applications
to which they are put without the quality and homolog distribution improvements which only fractional distillation can guarantee.
Thus, this separation is of vital importance within the fatty acid and derivative industries. Fractional distillation is industrially
a practical separative method for: (a) 16:0 and 18:0 fatty acids, such as those derived from hydrogenated fats and oils like
tallow, soybean, cottonseed soapstocks, palm oil and others; (b) 18:0, 20:0, 22:0, and 24:0 fatty acids from hydrogenated
fish oils or high erucic rapeseed oil; and (c) 8:0, 10:0, 12:0, and 14:0 fatty acids from the hydrogenated fatty acids from
the lauric oils group (coconut, palm kernel, babassu, etc.). While theoretically possible under idealized conditions in the
laboratory, it is not practical to separate palmitic, oleic, heptadecanoic, and stearic acids by means of fractional distillation 相似文献
13.
Hiroaki Konishi William E. Neff Timothy L. Mounts 《Journal of the American Oil Chemists' Society》1993,70(4):411-415
Chemical interesterification reaction conditions that provide regioselectivity regarding fatty acid positions in triacylglycerol
have been investigated. Sodium methoxide-catalyzed ester interchange between soybean oil and methyl stearate was performed
in hexane at low reaction temperature,i.e., 30 to 60°C. The results showed regioselectivity was obtained at 30°C. The ester interchange at 1,3-carbons progressed 1.7
times faster than at 2-carbon of the glycerol moiety of triacylglycerol at 24 h. Preheating of the mixture of reactant and
catalyst at 60°C for 15 min promoted catalyst activation to accelerate the interesterification while maintaining regioselectivity.
This method is believed to be feasible for modification of edible fats and oils.
Presented at the American Oil Chemists’ Society’s Annual Meeting, May 10–14, 1992, Toronto, Canada. 相似文献
14.
Arthur E. Waltking William E. Seery George W. Bleffert 《Journal of the American Oil Chemists' Society》1975,52(3):96-100
For more than a decade, numerous analytical methods have been proposed for the detection and measurement of polymers in vegetable
fats and oils. Many of the methods have been little more than laboratory curiosities, either because they were concerned with
only very specific compounds or were too cumbersome and time consuming to become very popular. More recently, a number of
methods in common use for analysis of fats and oils has been shown to be useful for indirectly measuring polymeric materials
in heat abused oils. The present report shows, by the use of gel filtration chromatography, the validity of two of the indirect
methods of estimating polymeric products of abused fats and oils. These methods are: the estimation of polymers through changes
in the iodine value and the measurement of retention materials on a gas liquid chromatographic column. A new simplified internal
standard gas liquid chromatographic procedure utilizing triglyceride standards also is presented. This latter method permits
estimating the degree of degradation of vegetable fats and oils by any laboratory capable of determining the fatty acid composition
of a sample by gas liquid chromatography.
Presented at the AOCS Meeting, Ottawa, Canada, September 1972. 相似文献
15.
G. B. D’Souza 《Journal of the American Oil Chemists' Society》1979,56(11):812A-819A
Historically, glycerol, a valuable by product of the fatty acid insutry, is priced higher in the market-place than any of
the common fatty acids. Glycerol “credit” from fat-splitting, frequently in time of economic stress, makes the difference
between a profitable stearic acid operation and an economically unsound one. Theoretical yields of glycerol for the common
fats and oils range from 9–13.5%; practical plant yields, corrected for FFA and upgrading yield losses, are 9–12.8% on 100%
glycerol basis, or 10.3–14.8% on an 88% glycerol basis. Glycerol “credit” per pound of fatty acid ranges from 1 to 3 cents/pound.
Upgrading “sweetwaters” from splitting operations in the fatty acid industry requires removal of dissolved salts, elimination
of color, and fat and oil impurities, concentration (evaporation of water) and/or distillation. For Twitchellized sweetwaters
this generally involves (a.) lime treatment. (b.) filtration, (c.) evaporation to half-crude, (d.) precipitation of excess
lime, (e.) filtration, (f.) evaporation to a concentration of 88–90%, and probably, (g.) distillation. For autoclave or continuous
process sweetwaters the upgrading includes (a.) light lime treatment, (b.) filtration, (c.) evaporation concentration to 88–90%,
and probably, (d.) distillation. Glycerol may also be upgraded by ion-exchange processing followed by evaporation concentration
in which distillation may be eliminated. Ion-exclusion (Dow process) is also feasible. Many special triglyceride products
are required of different fatty acid homolog distribution than those of the parent or hydrogenated fats and oils. These are
prepared by splitting the fats or hydrogenated oils, fractionating the fatty acids, upgrading the glycerol, and recombining
the desired fractionated acids with glycerol by reesterification. One example is high lauric triglyceride from coconut oil
suited for use as a coco butter substitute. 相似文献
16.
A. A. Ismail F. R. van de Voort G. Emo J. Sedman 《Journal of the American Oil Chemists' Society》1993,70(4):335-341
Rapid direct and indirect Fourier transform infrared (FTIR) spectroscopic methods were developed for the determination of
free fatty acids (FFA) in fats and oils based on both transmission and attenuated total reflectance approaches, covering an
analytical range of 0.2–8% FFA. Calibration curves were prepared by adding oleic acid to the oil chosen for analysis and measuring
the C=O band @ 1711 cm–1 after ratioing the sample spectrum against that of the same oil free of fatty acids. For fats and oils that may have undergone
significant thermal stress or extensive oxidation, an indirect method was developed in which 1% KOH/methanol is used to extract
the FFAs and convert them to their potassium salts. The carboxylate anion absorbs @ 1570 cm–1, well away from interfering absorptions of carbonyl-containing oxidation end products that are commonly present in oxidized
oils. Both approaches gave results comparable in precision and accuracy to that of the American Oil Chemists’ Society reference
titration method. Through macroprogramming, the FFA analysis procedure was completely automated, making it suitable for routine
quality control applications. As such, the method requires no knowledge of FTIR spectroscopy on the part of the operator,
and an analysis takes less than 2 min. 相似文献
17.
B. Panduranga Rao S. D. Thirumala Rao B. R. Reddy 《Journal of the American Oil Chemists' Society》1972,49(5):338-339
Rapid qualitative and quantitative methods for determining the free fatty acid (FFA) contents in common oils and fats are
reported. Qualitative method is based on the type of color developed in the presence of BDH indicators (Universal and “678”)
when a known excess of alkali is added to an alcoholic solution of oil or fat. By this method, low (0.0–0.25), medium (0.26–0.99)
and high (1.0 and above) FFA levels in fatty oils may be distinguished. Quantitative method is a simplified modification of
the usual procedure of determining the FFA contents of oils and fats by titration against standard alkali solution in the
presence of BDH Universal or “678” indicator. The results of the rapid methods agree well with those of the standard AOCS
method. 相似文献
18.
Dhan Lord B. Fortela Rafael Hernandez Emmanuel Revellame William Holmes Wayne Sharp Mark Zappi 《Journal of the American Oil Chemists' Society》2019,96(9):1073-1079
This study focuses on new interpretations of the published literature by statistically evaluating the potential of microbial lipids from activated sludge (AS) as alternatives to high-value oils and fats. There are two data analysis stages involved in this study after compilation and organization of fatty acid profiles from the literature databases: (1) comparison of fatty acid profiles of the cultivated AS lipids with that of oils and fats found in the literature databases, and (2) hierarchical cluster analysis of the fatty acids of the combined dataset of literature oils and fats, and the AS lipids. Results show that fatty acid profiles of lipids from cultivated AS were similar to the fatty acid profiles of some oils and fats of plant, animal, single-microbial cultures, and algal origins; hence, lipids from AS could be potential alternatives to specialty oils and fats. The cultivation conditions of AS during lipid content enhancement may influence lipid application. 相似文献
19.
Mustafa E. Tat Paul S. Wang Jon H. Van Gerpen Thomas E. Clemente 《Journal of the American Oil Chemists' Society》2007,84(9):865-869
Biodiesel is a fuel comprising mono-alkyl esters of medium to long-chain fatty acids derived from vegetable oils or animal
fats. Typically, engines operated on soybean-based biodiesel exhibit higher emissions of oxides of nitrogen (NOx) compared
with petroleum diesel. The increase in NOx emissions might be an inherent characteristic of soybean oil’s polyunsaturation,
because the level of saturation is known to affect the biodiesel’s cetane number, which can affect NOx. A feedstock that is
mostly monounsaturated (i.e. oleate) helps to balance the tradeoff between cold flow and oxidative stability. Genetic modification
has produced a soybean event, designated 335-13, with a fatty acid profile high in oleic acid (>85%) and with reduced palmitic
acid (<4%). This high-oleic soybean oil was converted to biodiesel and run in a John Deere 4045T 4.5-L four-stroke, four-cylinder,
turbocharged direct-injection diesel engine. The exhaust emissions were compared with those from conventional soybean oil
biodiesel and commercial No. 2 diesel fuel. There was a significant reduction in NOx emissions (α = 0.05) using the high-oleic soybean biodiesel compared with regular soybean oil biodiesel. No significant differences were
found between the regular and high-oleic biodiesel for unburned hydrocarbon and smoke emissions. 相似文献
20.
W. D. Pohle V. C. Mehlenbacher J. H. Cook 《Journal of the American Oil Chemists' Society》1945,22(5):115-119
Summary A method based upon oxidation of monoglyceride by periodic acid has been developed for the determination of monoglyceride
in fats and oils. The reaction and conditions that influence the determination have been described and discussed.
This paper was presented at the Chicago meeting of the American Oil Chemists’ Society, October 25–27, 1944. 相似文献