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Vernon W. Trost 《Journal of the American Oil Chemists' Society》1989,66(3):325-333
Normal phase preparative and semi-preparative liquid chromatography were used to isolate fractions of varying polarity from
corn, soybean and sunflowerseed oils. Reported here is the composition of one fraction, less polar than triglycerides, determined
by isolating the individual ?peaks? of a semi-preparative separation using as starting material the mix of compounds obtained
from a large scale separation. These peaks were then analyzed by high performance liquid chromatography (LC) gas chromatography
(GC), mass-spectrometry (MS) with and without GC, in both electron impact (EI) and chemical ionization (CI) modes, and carbon-13
nuclear magnetic resonance (NMR) spectroscopy. Semi-quantitative data were obtained for many of the components found in these
semi-preparative isolates including hydrocarbons, steryl esters, triterpenyl esters, phytyl esters and geranylgeranyl esters.
The weight percent and composition of the preparative fraction differed substantially among the three oils. Corn oil had the
greatest amount, at 1.25% of the starting oil, and was composed mostly of steryl and triterpenyl esters. Sunflowerseed oil,
at 0.7%, and soybean oil, at 0.3%, showed greater variety in that branched chain esters were included with the steryl/triterpenyl
distributions. 相似文献
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Z. J. Hawrysh M. K. Erin S. S. Kim R. T. Hardin 《Journal of the American Oil Chemists' Society》1995,72(10):1123-1130
The effects of canola, corn, partially hydrogenated soy (PHS), partially hydrogenated canola (PHC), and low-linolenate canola
(LLC) oils on sensory and chemical attributes of tortilla chips were determined initially, after Schaal storage for 8 and
16 d (S8 and S16), and after practical storage for 16 and 24 wk (P16 and P24). Fresh chips were similar to each other in characteristic
and off-odors/flavors, except that PHC chips had the lowest characteristic and highest off-odor/flavor. All S8 chips had similar
lower (P<0.001) characteristic and greater off-odor/flavor scores than hidden reference chips, but PHC chips had a more intense off-odor
than did LLC chips. After S16, canola chips had the lowest (P<0.001) characteristic and highest off-odor/flavor; all other chips were similar. At P16, canola, PHC, and LLC chips had slightly
higher (P<0.001) characteristic odor/flavor scores than other chips. After P16 and P24, all stored tortilla chips had lower characteristic
odor/flavor scores than hidden reference chips. Rancid, painty, buttery odor/flavor, and bitter flavor notes were detected
in Schaal and practically stored chips. Stored chips from all oils were similar in color and crispness. The peroxide value
and thep-anisidine value for oils extracted from Schaal-stored chips tended to support panelist data; results from similar analyses
of practically stored chips did not. Peroxide values andp-anisidine values for stored used frying oils and the corresponding sensory data for stored chips generally did not agree.
Results indicate considerable potential for increasing use of canola oil products for frying tortilla chips. 相似文献
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C. K. Lyon V. H. Garrett E. N. Frankel 《Journal of the American Oil Chemists' Society》1974,51(8):331-334
Castor, safflower, and oleic safflower oil derivatives with enhanced reactivity and hydroxyl group content were prepared by hydroformylation with a rhodium-triphenylphosphine catalyst, followed by hydrogenation. Rigid urethane foams prepared from these hydroxymethylated derivatives had excellent compressive strengths, closed cell contents, and dimensional stability. Best properties were obtained from hydroxymethylated polyol esters of castor acids. 相似文献
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Adult male rats were surgically given a drainage catheter in the main mesenteric lymph duct. After an overnight fast, five
groups of rats received intragastrically, in one bolus, butter, corn oil (CO), cod liver oil (CLO), menhaden oil (MO), or
ethyl esters of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids (K80). Intestinal lymph was collected in these conscious
animals, each hour during the first 6 h and in a single sample for the next 18 h. The absorption peak appeared earlier after
MO and CO than after CLO administration. The quantities of triglycerides recovered during the first 6 h were significantly
lower after butter (91 mg) and K80 (54 mg) administration than for the other three oils. No difference was observed between
the vegetable oil and the two marine oils (CO=173 mg, CLO=148 mg, MO=180 mg). The total triglyceride recovered in 24 h was
highest after CLO (410 mg) and lowest with K80 (146 mg). An increase in the weight percentage of some characteristic fatty
acids of the lipid mixtures was observed: oleic acid for butter, oleic and linoleic acids for CO, EPA and DHA for CLO, MO,
and K80. Chylomicrons were the largest with CO, more numerous and smaller with CLO, and the smallest with K80. Results obtained
illustrated the relation between gastrointestinal hydrolysis, enterocyte biochemical events, and lymph triglyceride absorption
profiles as related to the composition and distribution of triglyceride fatty acids. 相似文献
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Two ternary systems of fats were studied. In the first system, low-erucic acid rapeseed oil (LERO), hydrogenated lowerucic
acid rapeseed oil (HLERO), and palm oil (PO) were blended. In the second system, hydrogenated palm oil (HPO) was used instead
of PO and was blended with LERO and HLERO. The blends were then studied for their physical properties such as solid fat content
(SFC), melting curves by DSC, and polymorphism (X-ray). HPO showed the highest melting enthalpy after 48 h at 15°C (141±1
J/g), followed by HLERO (131±2 J/g), PO (110±2 J/g), and LERO (65±4 J/g). Binary phase behavior diagrams were constructed
from the DSC and X-ray results. Iso-line diagrams of partial-melting enthalpies were constructed from the DSC results, and
binary and ternary isosolid diagrams were constructed from the NMR results. The isosolid diagrams demonstrated formation of
a eutectic along the binary blend of PO/HLERO. However, no eutectic effect was observed along the binary lines of HPO/HLERO,
PO/LERO, HPO/LERO, or HLERO/LERO. The same results were found with the iso-line diagrams of partial-melting enthalpies. As
expected, addition of PO or HPO increased polymorphic stability in the β′ form of the HLERO/LERO mixture. 相似文献
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Lionel K. Arnold William G. Juhl Harold C. Arvidson Jr. 《Journal of the American Oil Chemists' Society》1954,31(9):393-394
Summary Data on the densities and viscosities of miscellas from trichloroethylene and cottonseed oil, fish oil, and beef tallow for
four different temperatures are presented. Equations, with the necessary constants, are given for calculating both densities
and viscosities. 相似文献
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The hypocholesterolemic efficacy of various polyunsaturated fatty acids was compared in rats given cholesterol-enriched diets.
Capybara oil (CO, linoleic+α-linolenic acids), horse oil (HO, α-linolenic acid), and sardine oil (SO, eicosapentaenoic+docosahexaenoic
acids) were added to diets at 50 g/kg. The weight gain, food intake, and liver weight in the CO-fed group were significantly
higher than those in other groups during the 6-wk experimental period. The serum total and very low density lipoprotein (VLDL)+intermediate
density lipoprotein (IDL)+low density lipoprotein (LDL) cholesterol concentrations of the CO-fed and SO-fed groups were significantly
lower than in the HO-fed group after 6 wk. The serum high density lipoprotein cholesterol concentration in the SO-fed group
was significantly higher than that in the CO-fed and HO-fed groups. The fecal neutral sterol concentration in the CO-fed group
was reduced significantly compared with the other groups, and the fecal bile acid concentration in the HO-fed group was significantly
higher than that in the SO-fed group. The results of this study demonstrate that CO lowers the serum total cholesterol and
VLDL+IDL+LDL-cholesterol concentrations in the presence of excess cholesterol in the diet as well as SO. 相似文献
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This paper examines the effect of foam density, oil viscosity, and temperature on the oil sorption behavior of polyurethane foams. Four polyurethane foams with different densities and two oil types with different viscosities were investigated. The amount of oil uptake was measured gravimetrically. Oil transport through the foams was analyzed by nondestructive X‐ray microtomography. Oil sorption capacity increased significantly with the decrease in foam density, due to the increase in the number of open cells. The oil sorption capacity depended only slightly on sorption temperature and oil viscosity. X‐ray visualization allowed pore filling behavior to be observed directly, and further scope to extend the technique is revealed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 360–367, 2006 相似文献
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Effect of nitrogen and zinc fertilization and plant growth retardants on cottonseed, protein, oil yields, and oil properties 总被引:3,自引:0,他引:3
Zakaria M. Sawan Saeb A. Hafez Ahmed E. Basyony 《Journal of the American Oil Chemists' Society》2001,78(11):1087-1092
The increase in the population in Egypt makes it imperative to explore promising approaches to increase food supply, including
protein and oil, to meet the needs of the Egyptian people. Cotton is the principal crop of Egyptian agriculture. It is grown
mainly for its fiber, but cottonseed products are also of economic importance. Cottonseed is presently the main source of
edible oil and meal for livestock in Egypt. Field experiments were conducted in two successive seasons at the Agricultural
Research Center (Giza, Egypt) on cotton (Gossypium barbadense L. cv. Giza 75) to determine the effect of nitrogen (N) fertilizer rate (107 and 161 kg of N/ha applied as ammonium nitrate
containing 33.5% N in two equal doses at 6 and 8 wk after sowing), together with foliar applications of plant growth retardants
(mepiquat chloride “Pix”, chloromequat chloride “Cycocel”, and daminozide “Alar”, each applied once at 288 g active ingredient/ha,
after 75 d from sowing) and zinc (Zn) (applied in chelated form after 80 and 95 d from sowing at 48 g of Zn/ha) on seed, protein
and oil yields and oil properties of cotton. The higher N-rate, as well as the application of all growth retardants and Zn,
resulted in an increase in cottonseed yield, seed protein content, oil and protein yields/ha, seed oil refractive index, unsaponifiable
matter, and total unsaturated fatty acids (oleic and linoleic). These treatments tended to decrease oil acid value, saponification
value, and total saturated fatty acids. The seed oil content tended to decrease as N-rate increased and increased with the
application of all growth retardants and Zn. There were some differences between Pix, Cycocel, and Alar regarding their effects
on the studied characters. The highest increase in seed, oil, and protein yields/ha was found with Pix, followed by Cycocel.
The Cycocel treatment gave the lowest total saturated fatty acids oil content, followed by Alar. 相似文献
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C. E. Elson G. L. Underbakke P. Hanson E. Shrago R. H. Wainberg A. A. Qureshi 《Lipids》1989,24(8):677-679
To test the hypothesis that non-sterol mevalonate pathway end products lower serum cholesterol levels, we asked 22 hypercholesterolemic
subjects (315±9 mg cholesterol/dl) to take a daily capsule containing 140 mg of lemongrass oil, an essential oil rich in geraniol
and citral. The paired difference in serum cholesterol levels of subjects completing the 90-day study approached significance
(P<0.06, 2-tailed t-test). The subjects segregated into two groups, one consisting of 14 subjects resistant to the protocol
and the other consisting of 8 subjects who responded. Paired differences in cholesterol level at 30, 60 and 90 d for resistant
subjects were +2±6, +2±7 and −1±6 mg/dl; paired differences for the responding subjects were −25±10 (p<0.05), −33±8 (p<0.01)
and −38±10 (p<0.025), respectively. The paired difference (+8±4) in the cholesterol levels of six responders 90 days after
the discontinuation of lemongrass oil was not significant. 相似文献
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L. H. Wiedermann 《Journal of the American Oil Chemists' Society》1981,58(3):159-166
This subject deals with the removal of the fat-soluble impurities from crude soybean oil. These impurities may be present
in true solution or in a colloidal state; their effective removal is necessary to achieve quality standards for end-use products.
The processing step options for the removal of these impurities in any given situation are easily defined; the conditions
and practices used, however, are the primary concern of this paper. International trading of soybean oil mandates the degumming
step. The increased use of import/export soybean oil increases the importance of this processing practice. Pretreatment and
effective contact time are the critical issues. Refining, as a specific process, deals primarily with free fatty acid removal,
with or without simultaneous degumming as a single-step operation. State-of-the-art wet, chemical refining practices are described,
and the current limitations and future opportunities for the physical refining of soybean oil are discussed. The importance
of the bleaching step cannot be overstated and it should be noted that color reduction is only coincidentally achieved. The
primary function of the bleaching process is to remove oxidative breakdown products, and the degree or level of treatment
should be consistent with that objective. Underbleaching and thermal decolorization (deodorization) of soybean oil are misguided
practices. Once “cleaned-up” through adequate bleaching, an oil should be guarded against thermal/oxidative abuse. 相似文献