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1.
Fatty acid and triglyceride compositions of phulwara butter (Madhuca butyraceae seed fat) have been determined by combination of the techniques of systematic crystallization at low temperatures, pancreatic
lipase hydrolysis, and gas liquid chromatography of methyl esters. The percentages of individual fatty acids were found to
be palmitic, 55.6; stearic, 5.2; oleic, 35.9; and linoleic, 3.3. The special characteristic of the phulwara butter is its
content of POP, 52.5%; PLP, 4.9%; POSt, 8.6%; POO, 14.4% and PPP, 7.7% (P, palmitic; St. stearic; O, oleic; and L, linoleic).
2-Monoglycerides obtained by lipolysis of this fat and its least soluble fraction contained 13,0% and 29.3% saturated acids,
respectively. Phulwara butter may be a potential source of palmitic acid for the pharmaceutical industry. 相似文献
2.
Fatty acid profile of milk fat can be modified by cow feeding strategies. Our aim was postprandially and after 4 wk to compare
the effect of a modified milk fat (M diet) [with 16% of the cholesterolemic saturated fatty acid (C12–16) replaced by mainly
oleic and stearic acids] with the effect of D diet, including a conventional Danish milk fat on plasma lipids and lipoproteins.
A side effect of the cow feeding regime was a 5% (w/w) increase in trans fatty acid in M diet. Eighteen subjects were fed for two periods of 4 wk strictly controlled isoenergetic test diets with
40% of energy from total fat and the same content of dietary cholesterol in a randomized study with cross-over design. Contrary
to expectations, fasting low density lipoprotein (LDL) cholesterol concentration did not differ after the experimental periods.
However, M diet resulted in a higher fasting total triacylglycerol concentration compared to D diet (P=0.009). Postprandial samples were taken at two different occasions (i) at day 21, after breakfast and lunch and (ii) on the
last day of the study 2, 4, 6, and 8 h after a fat load. Postprandial plasma triacylglycerol and chylomicron triacylglycerol
showed higher peak values after D diet than M diet (interaction effect, diet × times P<0.05). In conclusion, M diet did not lower LDL cholesterol compared to D diet. Thus any cholesterol-lowering effect of oleic
and stearic acids may have been obscured by the high content of cholesterol-raising saturated fatty acids in milk fat. A higher
content of the trans fatty acids in M diet might have counteracted the cholesterol neutral/decreasing effect and increased plasma triacylglycerol. 相似文献
3.
Fatty acid esterification by cell free preparations of bovine mammary tissue was investigated to determine if the type of
long chain fatty acid supplied might influence the rate of triglyceride synthesis by that tissue. Homogenates of lactating
bovine mammary tissue esterified14C-fatty acids into glycerides at rates dependent upon chain length and degree of unsaturation. Palmitic, stearic, oleic and
linoleic acids were esterified at rates consistent with their concentration in milk fat. A comparison of free fatty acid concentrations
of mammary tissue with levels saturating esterification suggested that supply of fatty acids does not limit glyceride synthesis.
Certain combinations of fatty acids were facilitory, competitive or inhibitory to esterification. Stearic acid complimented
esterification of palmitic and oleic acids. Unlabeledtrans-11-octadecenoic acid did not compete with14C-palmitate as efficiently in the esterification process as did unlabeledcis-9-octadecenoic acid, indicating that the mammary gland may preferentially esterify thecis-isomer of C-18∶1. Linoleic acid inhibited esterification of palmitic, stearic and oleic acids.
Michigan Agricultural Experiment Station Journal Article No. 5100. 相似文献
4.
Milk fat globules: Fatty acid composition,size and in vivo regulation of fat liquidity 总被引:3,自引:0,他引:3
Populations of large and small milk fat globules were isolated and analyzed to determine differences in fatty acid composition.
Globule samples were obtained by centrifugation from milks of a herd and of individual animals produced under both pasture
and barn feeding. Triacylglycerols of total globule lipids were prepared by thin layer chromatography and analyzed for fatty
acid composition by gas chromatography. Using content of the acids in large globules as 100%, small globules contained fewer
short-chain acids, −5.9%, less stearic acid, −22.7%, and more oleic acids, +4.6%, mean values for five trials. These differences
are consistent with alternative use of short-chain acids or oleic acid converted from stearic acid to maintain liquidity at
body temperature of milk fat globules and their precursors, intracellular lipid droplets. Stearyl-CoA desaturase (EC 1.14.99.5),
which maintains fluidity of cellular endoplasmic reticulum membrane, is suggested to play a key role in regulating globule
fat liquidity. Possible origins of differences between individual globules in fatty acid composition of their triacylglycerols
are discussed. 相似文献
5.
Trans-10, cis-12 conjugated linoleic acid (CLA) is a potent inhibitor of milk fat synthesis in the cow and similarly reduces milk fat in rodents. The objective of this study was to determine whether dietary fat can overcome CLA inhibition of milk fat concentration in lactating mice. Wild type C57Bl/6J mice (n = 31) were fed semipurified diets containing either low fat (LF; 4% fat) or high fat (HF; 23.6% fat) starting 4–6 days postpartum. Dietary fat was increased by inclusion of high oleic sunflower oil. After 2 days on the experimental diets, lactating dams were orally dosed with either water (control) or trans-10, cis-12 CLA (20 mg/day) for 5 days. CLA treatment decreased pup growth similarly in both HF and LF diets. Milk fat percent was increased over 16% by the HF diet and decreased over 12% by CLA, but there was no interaction of dietary fat and CLA. Both CLA and the HF diet reduced the proportion of short- and medium-chain fatty acids that originate from de novo synthesis, and there was no interaction of diet and CLA. CLA had no effect on the percent of preformed fatty acids, but the HF diet increased their abundance. Dietary fat and CLA both modified mammary expression of lipogenic enzymes and regulators, but no interactions were observed. In conclusion, CLA reduced milk fat concentration and litter growth, but these effects were not overcome by increased dietary fat from high oleic sunflower oil. CLA inhibition of milk fat in the mammary gland is not substrate dependent, and the mechanism is independent from dietary supply of oleic acid. 相似文献
6.
D. Precht E. Frede H. Hagemeister H. Timmen 《European Journal of Lipid Science and Technology》1985,87(3):117-126
Variations of Cow's Milk Fat as Affected by Feeding with Special Consideration of Regulation Mechanisms of Fat Metabolism Milk fat composition is highly affected by the conditions of feeding, which again may have considerable consequences for the quality of several dairy products. In order to establish possible variations in physical and chemical properties of the milk fat as depending on the nutritional status of the cow, a small herd of cows was successively subjected to different defined feeding conditions (barn feeding, pasture feeding, energy deficit). The investigations indicated that from barn feeding to pasture feeding to energy deficit the proportions of oleic acid and of long chain triglycerides increased and the proportions of short and medium chain fatty acids and triglycerides decreased. In spite of highly differing fat compositions relatively constant values for the viscosity and the average triglyceride molecular weight were obtained; also various characteristics from the melting and solidification curves were nearly identical. The solid/liquid ratios approached at higher temperatures. These results point to the existence of regulation mechanisms, in the course of which the flow and melting properties are kept within the required narrow ranges by an opposite behaviour of the proportions of short chain fatty acids and oleic acid. With pasture feeding, compared with barn feeding, all oleic acid isomers and linoleic acid increased, with energy deficit the proportions of these acids are at the low level of barn feeding. These results as well as the continuous decrease of the cholesterol content from barn to pasture to energy deficit are explained on the basis of the different pathways of fat metabolism; deficit are explained on the basis of the different pathways of fat metabolism; furthermore the proportions of trans C18: 1 acids are discussed in connection with the milk fat content. The milk fat globules are particularly large and unstable at the period of energy deficit. Consequently, quality deterioration of whipping cream (creaming, plug formation) and other dairy products (lipolysis) can be expected. 相似文献
7.
D. Precht 《European Journal of Lipid Science and Technology》1990,92(4):153-161
Quantitative Detection of Milk Fat in Chocolate Mixtures I: Determination of Milk Fat in Cocoa Butter New methods for the quantitative determination of milk fat proportions in cocoa butter samples based on gas chromatographic analysis of fatty acids and triglycerides are described. 45 different cocoa butter types from 25 countries and 755 milk fat samples were analyzed by taking different feeding conditions into account. By means of triglyceride measurements mean relative deviations of approximately 5% from the 2–10% milk fat additions were established for known cocoa butter- and unknown milk fat composition. With completely unknown initial fats a mean relative deviation of approximately 6% was measured using fatty acid analysis. 相似文献
8.
Julio A. Solís‐Fuentes Carmen Durn‐de‐Bazúa 《European Journal of Lipid Science and Technology》2003,105(12):742-748
Samples of cacao butter (CB), mango seed almond fat (Mangifera indica var. Manila) (MAF), and zapote mamey seed almond fat (Pouteria sapota) (ZMAF), were analyzed for their fatty acid composition and were mixed according to a 3‐factor simplex‐lattice design. Mixtures were stabilized, their fusion and crystallization thermal behavior, and solid fat contents were evaluated using differential scanning calorimetry. Ternary phase behavior was analyzed with isosolid diagrams. Results showed that the main fatty acids in the fats were oleic, stearic, and palmitic acids: CB: 31.1, 35.5, and 27.8%; MAF: 37.5, 42.6 and 9.9%, and ZMAF: 50.0, 27.2 and 12.0%, respectively. Fusion behavior showed a single curve with only one maximum and one small shoulder for CB and MAF, and three maximum points for ZMAF. Crystallization was also a single curve with only one maximum for the three fats. Solid fat contents at 21.1 °C were: CB: 87.5; MAF: 68.5 and ZMAF: 6.6%. Ternary phase behavior showed that these fats can support preparation of mixtures with different compositions that could become equivalent to cocoa butter for use in alimentary, pharmaceutical, and cosmetic industries. 相似文献
9.
Pancreatic lipase hydrolysis was used to determine the distribution of fatty acids in the milk triglycerides of four species of monkeys and of human milk. The patterns of the major fatty acids were generally similar in all species examined, but there were some differences in the relative concentrations of individual fatty acids esterified at either the 2 or 1,3 positions. Caprylic, stearic, oleic, and linoleic acids were found predominantly at the 1,3 positions; in contrast, lauric, myristic, palmitic, and palmitoleic were concentrated at the 2 position. Monkey milk fats had greater proportions of these acids at the respective positions than did bovine milk fat. Also, the monkey fats were relatively uniform both in total unsaturated fatty acids (41–48%) and in the proportion of these esterified at the 2 position (19–26%). In general, both the fatty acid composition and the specific distribution of fatty acids in the monkey milk fats more closely resembled the patterns in human milk fat than did those in ruminant milk fats. 相似文献
10.
A. S. El-Nockrashy C. M. Lyman J. W. Dollahite 《Journal of the American Oil Chemists' Society》1963,40(1):14-17
Acute oral toxicity studies were carried out on cottonseed pigment glands, gossypol, diaminogossypol and gossypurpurin using
rats as experimental animals. It was found that both diaminogossypol and gossypurpurin are considerably less toxic than pure
gossypol. The pigment glands were more toxic than gossypol and it was concluded that the toxicity of pigments cannot be accounted
for entirely on the basis of their gossypol content.
Administration of gossypol with cottonseed oil orSterculia foetida oil, both of which contain cyclopropene fatty acids, increased the toxicity very slightly over that found when gossypol was
administered in corn oil. In the case of corn oil andSterculia foetida oil, the difference was statistically significant.
Less gossypol was also found in the feces when the test dose was given in cottonseed oil orS. foetida oil indicating a possible effect of the cyclopropene fatty acids in increasing gossypol absorption. 相似文献
11.
Joel Bitman L. P. Dryden H. K. Goering T. R. Wrenn R. A. Yoncoskie L. F. Edmondson 《Journal of the American Oil Chemists' Society》1973,50(3):93-98
Polyunsaturated milk has been produced by feeding cows safflower oil enclosed in a casein coat protected with formaldehyde
(SOC-F) or formaldehyde-treated soybean (SB) preparations. The efficiency of transfer of dietary 18∶2 ranged from 17 to 42%
for various lots of SOC-F and was only 2–8% for SB (per cent transfer=18.2 in milk fat per dietary 18∶2×100). The 18∶2 content
of the milk fat increased from basal levels of 2–3% of total fatty acids to 35% with certain SOC-F levels and 7% with SB.
Major compensatory changes were noted in 14∶0 and 16∶0 fatty acids. Blood cholesterol, triglycerides and nonesterified fatty
acids all increased markedly as cows were fed increasing amounts of SOC-F. There was no increase in cholesterol in the milk.
Presented at the AOCS Meeting, Los Angeles, April 1972. 相似文献
12.
P. M. Kris-Etherton 《European Journal of Lipid Science and Technology》1993,95(12):448-452
We conducted two clinical studies to examine the effects of diets high in stearic acid and lauric + myristic acid on plasma lipids and lipoproteins of healthy young men. In the first study subjects (n = 15) were fed whole food diets high in cocoa butter, butter, olive oil and soybean oil. In the second study, subjects were fed diets very high in saturated fatty acids (> 20% of calories) that were high in either stearic acid (from cocoa butter or milk chocolate) or lauric + myristic acid (from butter). In the first study, cocoa butter elicited a neutral cholesterolemic effect, whereas the butter diet was hypercholesterolemic and the olive oil and soybean oil diets were hypocholesterolemic. In the second study, the diets high in stearic acid did not raise plasma total and LDL-cholesterol levels, whereas, as in the first study, butter was markedly hypercholesterolemic. Regression analyses performed on the individual data from these two clinical studies were conducted to establish the cholesterolemic effects of individual fatty acids. The bestfitting linear regression equations relating ΔTC (change in plasma total cholesterol) was: ΔTC = 2.3 ΔC14:0 + 3.0 ΔC16:0-0.8 ΔC18:0-1.0 ΔPUFA, where Δ fatty acid = change in intake expressed as percent of calories. This predictive equation separates stearic acid from the other long-chain saturated fatty acids and suggests that it has an independent cholesterol-lowering effect. In conclusion, stearic acid is a unique long-chain saturated fatty acid. 相似文献
13.
Protection of dietary polyunsaturated fatty acids against microbial hydrogenation in ruminants 总被引:4,自引:0,他引:4
T. W. Scott L. J. Cook S. C. Mills 《Journal of the American Oil Chemists' Society》1971,48(7):358-364
Polyunsaturated fatty acids are normally hydrogenated by microorganisms in the rumen. Because of this hydrogenation ruminant
triglycerides contain very low proportions of polyunsaturated fatty acids. A new process is described whereby polyunsaturated
oil droplets are protected from ruminal hydrogenation by encapsulation with formaldehyde-treated protein. The formaldehyde-treated
protein resists breakdown in the rumen thereby protecting the fatty acids against microbial hydrogenation. When these protected
oils are fed to ruminants the formaldehydeprotein complex is hydrolyzed in the acidic conditions of the abomasum and the fatty
acids are absorbed from the small intestine. This results in substantial changes in the triglycerides of plasma, milk and
depot fats, in which the proportion of polyunsaturated fatty acids is increased from 2–5% to 20–30%. These effects are observed
in the plasma and milk within 24–48 hr of feeding while a longer period is necessary to alter the composition of sheep depot
fat. The implications of these findings are discussed in relation to human and ruminant nutrition. 相似文献
14.
L. J. Filer Jr. Samuel J. Fomon Thomas A. Anderson Thomas L. Nixt Dean W. Andersen 《Lipids》1974,9(8):536-540
Fatty acid composition of carcass and liver and proximate analysis of liver were studied in 14–28 day old Pitman-Moore miniature pigs, 26 sow-reared and 30 fed a semisynthetic diet in which the fat was lard. With increasing age, fat of carcass, but not of liver, became significantly more unsaturated. The percentage of palmitic acid (16∶0) and total saturated fatty acids was significantly greater and the percentage of linoleic acid (18∶2) and total unsaturated fatty acids significantly less in carcasses of male than of female pigs. No sex-related differences in proximate or fatty acid composition of the liver were noted. Carcasses of sow-reared pigs contained significantly greater percentages of myristic (14∶0), palmitoleic (16∶1), and linoleic acids and significantly lesser percentages of stearic (18∶0) and oleic (18∶1) acids than did those of pigs fed the semisynthetic diet. Diet-related differences in fatty acid composition of liver closely paralleled those of carcass, although liver contained markedly greater percentages of stearic and arachidonic (20∶4) acids and lesser percentages of palmitoleic and oleic acids than did carcass. Diet-related differences in fatty acid composition of carcass and liver are discussed in relation to the fatty acid composition of dietary fat (sow milk and lard). 相似文献
15.
The changes in the triacylglycerol (TAG) composition of colostrum fat of three cows were studied. In addition to the determination
of fatty acid composition by gas chromatography, the distribution of TAG according to the acyl carbon number (ACN) and molecular
weight was analyzed utilizing both supercritical fluid chromatography (SFC) and ammonia negative-ion chemical ionization mass
spectrometry (MS). Colostrum TAG contained substantially less stearic and oleic acids and more myristic and palmitic acids
than the normal Finnish milk fat. The major trends in the changes of fatty acids and TAG were similar for each cow, although
clear differences between individuals were found. During the first week of parturition, the proportions of short-chain fatty
acids (C4–C10) typically increased as well as those of stearic and oleic acids, whereas the relative amounts of C12–C16 acids decreased, especially those of myristic and palmitic acids. Distinct changes occurred also in TAG distributions: the
proportions of molecules with ACN 38–40 increased and those with ACN 44–48 decreased. Although there were distinct differences
between individuals shortly after delivery, both the fatty acid compositions and TAG distributions of the milk samples of
the cows started to resemble each other after one week. The theoretical profiles of colostrum TAG calculated based on the
fatty acid compositions differed clearly from the ACN distributions analyzed by SFC and MS. Thus, the analysis of TAG is essential,
because the changes in molecular species composition of colostrum TAG cannot be estimated according to the fatty acid analysis
alone. 相似文献
16.
P. K. Pal D. K. Bhattacharyya S. Ghosh 《Journal of the American Oil Chemists' Society》2001,78(1):31-36
This work primarily aims to further modify the stearin fractions, obtained from anhydrous milk fat, after fractionation by
dry process and by solvent process using isopropanol, for extending their scope of utilization in edible fat products. Butter
stearin fractions, on blending with liquid oils like sunflower oil and soybean oil in different proportions, offer nutritionally
important fat products with enriched content of essential fatty acids like C18∶2 and C18∶3. The butter stearin fraction from isopropanol fractionation, when interesterified with individual liquid oils by Mucor miehei lipase as a catalyst, yields fat products having desirable properties in making melange spread fat products with reasonable
content of polyunsaturated fatty acids and almost zero trans fatty acid content. 相似文献
17.
The component fatty acids of the fat elaborated byAspergillus terreus Thom, which was found to be a promising mold for the production of fat, have been studied. The fat has, based on gas liquid
chromatographic evidence, 0.1% lauric, 1.9% myristic, 23.4% palmitic, 0.1% palmitoleic, 0.3% stearic, 14.1% oleic, 39.4% linoleic
and 20.7% linolenic acids. The presence of large proportions of linoleic and linolenic acids suggests technological interest
for the fat. 相似文献
18.
Hepatocyte plasma membranes were isolated from the livers of mice fed either a low fat diet or high fat diets containing polyunsaturated
or saturated fat. The combined rate and isopycnic ultracentrifugation technique which was used produced highly purified hepatocyte
plasma membrane fractions. The efficacy of the procedure was checked by electron microscopy and the assay of marker enzymes
for the different subcellular organelles. Mice were maintained on a low fat diet until 60–70 days of age, when they were fed
high fat diets containing polyunsaturated or saturated fat. The hepatocyte plasma membrane lipids of mice fed the polyunsaturated
fat diet for 4 wk contained increased proportions of the major dietary unsaturated fatty acid, linoleic acid, and increased
proportions of arachidonic acid. The proportion of linoleic and arachidonic acids decreased with continued feeding of the
polyunsaturated fat diet. The hepatocyte plasma membrane lipids of mice fed the saturated fat diet contained increased proportions
of oleic acid. 相似文献
19.
Physicochemical and thermal characterization of seed oil from Mexican mamey sapote <Emphasis Type="Italic">(Pouteria sapota)</Emphasis>
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Betsabé Hernández-Santos Edgar Sánchez-Ortega Erasmo Herman-Lara Jesús Rodríguez-Miranda Carlos A. Gómez-Aldapa Fernanda Peryronel Alejandro G. Marangoni Cecilia E. Martínez-Sánchez 《Journal of the American Oil Chemists' Society》2017,94(10):1269-1277
The aim of this research was to perform a physicochemical characterization of native mamey sapote seed oil [Pouteria sapota (Jacq.) H.E. Moore and Stearn]. Mamey sapote seed oil showed good oxidative stability as it had low peroxide, free fatty acid, and p‐anisidine values. The main fatty acids present in the oil were palmitic, stearic and oleic acid, constituting five major triacylglycerides families: PLP, POP, StOO, POSt and StOSt. Crystallization and melting points of the oil were ?37.7 and 23.84 °C, respectively. The oil had higher SFC when the temperature was lower than 10 °C. X‐ray diffraction patterns showed that prolonged storage times lead to the formation of β crystals. Micrographs showed granular crystals (91–105 μm), with needle edges similar to cocoa butter. In addition, mamey sapote seed oil can be used in confectionery products or as a possible substitute for cocoa butter to improve and obtain good‐quality products. 相似文献
20.
Karin Nuernberg Ulrich Kuechenmeister Gerd Nuernberg Margitta Hartung Dirk Dannenberger Klaus Ender 《European Journal of Lipid Science and Technology》2006,108(7):554-560
The purpose of the study was to assess changes in the fatty acid composition of raw and grilled pig muscles after different storage periods. A total of 13 female and 12 castrated Pietrain×German Landrace pigs were fed a basal concentrate diet supplemented with 5% olive oil or 5% linseed oil during the growing‐finishing period. An entire cut of the pork loin with bone (15th rib to 5th lumbar vertebra) was stored at 5 °C for 48, 96 or 144 h. Simultaneous analyses of intramuscular fat and lipid composition were carried out on raw and grilled longissimus muscles following different storage intervals. Dietary inclusion of linolenic acid by linseed oil feeding effectively increased the long‐chain n‐3 fatty acids, whereas in the olive oil group the oleic acid in pork was higher. Mean total lipid ranged from 1.8 to 2.3% for raw and from 2.6 to 3.5% for grilled pork chops. The relative proportions of lauric acid, stearic acid and oleic acid significantly increased with storage time, while the percentages of linoleic, arachidonic, eicosapentaenoic acid and the sum of polyunsaturated fatty acids, especially n‐6 fatty acids, were decreased. Compared with raw muscle, grilling affected the relative fatty acid profile only slightly. Related to the original weight, storage and grilling increased the total fatty acid contents and the sum of saturated, monounsaturated, n‐6 and n‐3 fatty acids of loin chops, as a result of water losses. 相似文献