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1.
Variability in fatty acid compositions of peanuts imported from six different countries into the United States were studied to determine their effect on processing and storage conditions. The oil content ranged from 44.1 to 50.4%. Major fatty acids, palmitic acid (C16:0), oleic acid (C18:l), and linoleic acid (C18:2) ranged from 8.6 to 12.7, 35.9 to 61.1 and 21.7 to 44.2%, respectively. Oleic and lino-leic acids together comprised ca. 78.0–83.0% of the total fatty acids. Highly significant differences (P<.01) in fatty acid compositions were obtained between samples and between locations (countries of origin). Indicators of stability of the peanut samples as measured by the oleic/linoleic acid ratio (O/L) and iodine value (IV) of the extracted peanut oils showed variable but significant differences (P <.05) between locations. Generally, higher O/L ratios corresponding to lower IV indicate better stability and longer shelf-life of the samples.  相似文献   

2.
The seed oils from twenty-five Conifer species (from four families—Pinaceae, Cupressaceae, Taxodiaceae, and Taxaceae) have been analyzed, and their fatty acid compositions were established by capillary gas-liquid chromatography on two columns with different polarities. The oil content of the seeds varied from less than 1% up to 50%. Conifer seed oils were characterized by the presence of several Δ5-unsaturated polymethylene-interrupted polyunsaturated fatty acids (Δ5-acids) with either 18 (cis-5,cis-9, 18∶2,cis-5,cis-9,cis-12 18∶3, andcis-5,cis-9,cis-12,cis-15 18∶4 acids) or 20 carbon atoms (cis-5,cis-11 20∶2,cis-5,cis-11,cis-14, 20∶3, andcis-5,cis-11,cis-14,cis-17 20∶4 acids). Pinaceae seed oils contained 17–31% of Δ5-acids, mainly with 18 carbon atoms. The 20-carbon acids present were structurally derived from 20∶1n-9 and 20∶2n-6 acids. Pinaceae seed oils were practically devoid of 18∶3n-3 acid and did not contain either Δ5-18∶4 or Δ5-20∶4 acids. Several Pinaceae seeds had a Δ5-acid content higher than 50 mg/g of seed. The only Taxaceae seed oil studied (Taxus baccata) had a fatty acid composition related to those of Pinaceae seed oils. Cupressaceae seed oils differed from Pinaceae seed oils by the absence of Δ5-acids with 18 carbon atoms and high concentrations in 18∶3n-3 acid and in Δ5-acids with 20 carbon atoms (Δ5-20∶3 and Δ5-20∶4 acids). Δ5-18∶4 Acid was present in minute amounts. The highest level of Δ5-20∶4 acid was found inJuniperus communis seed oil, but the best source of Δ5-acids among Cupressaceae wasThuja occidentalis. Taxodiaceae seed oils had more heterogeneous fatty acid compositions, but the distribution of Δ5-acids resembled that found in Cupressaceae seed oils. Except forSciadopytis verticillata, other Taxodiaceae species are not interesting sources of Δ5-acids. The distribution profile of Δ5-acids among different Conifer families appeared to be linked to the occurrence of 18∶3n-3 acid in the seed oils.  相似文献   

3.
The oil content and fatty acid composition of commercially important Turkish fish species (anchovy,Engraulis encrasicholus; freshwater rainbow trout,Salmo gairdneri; and cultured salmon,S. salar) were determined. Palmitic (16∶0), palmitoleic (16∶1), oleic (18∶1), and docosahexaenoic (22∶6) acids were the most abundant fatty acids in all species. Eicosapentaenoic acid (20∶5) was twice as high in the anchovy oil as in the rainbow trout and salmon oils. Significant quantities of linoleic acid (18∶2) and docosahexaenoic acids (22∶6) were found in both rainbow trout and salmon samples. The individual fatty acid data obtained from rainbow trout and salmon were similar to each other. All three fish species contain high levels of n-3 polyunsaturated fatty acids and would be suitable for inclusion in the formulation of low-fat highly unsaturated diets.  相似文献   

4.
Twenty sunflower(Helianthus annuus L.) introductions and the variety Mammoth Kussian were grown at Experiment, Georgia. Total oil, fatty acid composition, and other agronomic characteristics were used to evaluate the various introductions. Total oil content varied from 17.7 to 32.7%. All introductions were relatively low in palmitic, stearic, linolenic, and behenic acids. About 90% of the oil was composed of oleic and linoleic acids, and there was considerable variation in the ratios of these two fatty acids. Seed yields varied from 329 to 3,224 lb per acre and were related to the number and size of flowers. The more profusely flowering and higher yielding introductions originated in countries of lower latitudes.  相似文献   

5.
Phospholipid content and fatty acid composition of human heart were determined on 36 biopsy specimens collected during open heart surgery. The main phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and sphingomyelin (SPH) were separated by HPLC, quantified, and converted to fatty acid methyl esters which were chromatographed on capillary GLC columns. Sex and age (mainly 40–70) of patients had no significant influence on the relative distribution of phospholipid classes and only a slight effect on fatty acid composition. Incorporation oftrans 18∶1 in phospholipid classes was low.cis andtrans octadecenoic isomers seemed to be selectively incorporated, the Δ9 and Δ11cis ortrans isomers being predominant. Human and rat data were compared, and some species differences were noticed. In human PC, palmitic acid is higher and stearic acid much lower than in rat PC. Saturated dimethyl acetals (16∶0 and 18∶0) in PC and PE were greater for humans. Incorporation of 20∶4 n−6 in human PE is higher than in rat PE.  相似文献   

6.
Guayule, a perennial desert plant, is being developed for domestic production of natural rubber, a strategic commodity for which the United States presently depends totally on foreign sources. At present, rubber alone is not sufficient to make guayule a commercial crop, and additional revenues are being sought from by-products. Because guayule flowers profusely during several years of growth before it is harvested for rubber, seed may also contribute to the economics of guayule production. Seed from 120 plants, including 20 genotypes with 36, 37, 54 and 72 chromosomes, were analyzed for oil content and fatty acid composition. Oil content ranged from 17.1 to 30.5%. On average, seed from diploid and aneuploid plants (with 36 and 37 chromosomes) contained 40.4% more oil than the seed from polyploid plants. The oil consisted of four fatty acids—palmitic (8.7–11.5%), stearic (3.7–6.2%), oleic (6.5–13.9%) and linoleic (69.1–80.2%)—at all ploidy levels. Guayule seed oil was similar to the seed oil from high-linoleic safflower varieties. The use of genetic variation to increase seed yield and seed oil will depend on the absence of negative correlation between oil and rubber production.  相似文献   

7.
The fatty acid metabolism during germination of a special variety of peanuts treated with growth regulators, viz., GA, AA, Suc, Sul, MH and DW have been studied in sterile media for 1, 3, 6, 10, 14 and 18 days. No marked variation in the oil content of the control and the treated seeds is found during the initial period of germination. Initial growth is explained on the basis of energy supplied by the FFA and carbohydrates (as they are found decreasing during the 24 hr of germination). Practically no accumulation of FFA is observed throughout the complete period of germination. The mode of utilization of neutral oil with the period of germination is correlated with growth. The varied effect of growth regulators on the fat metabolism is explained assuming their various effects on mitochondria, the enzyme center, and on the process of photosynthesis. Active metabolism is marked from the sixth day of germination for both treated and control seeds. From the beginning of germination, interconversion of fatty acids is marked. Metabolism of fatty acids during germination is reported with the preferential utilization of 18:2 acid.  相似文献   

8.
The cyclopropenoid acid content of oils extracted from 22 commercial varieties and 3 botanical species of cottonseed have been determined. The malvalic acid content determined by HBr titration varied from a low of 0.56% to a high of 1.17%. Iodine values of the oils ranged from 96.8 to 111.6 No definite correlation could be established between iodine value and malvalic acid content. Equations for regression lines for the major acids have been calculated from plots of fatty acid composition vs. iodine value. The high degree or correlation suggests that for commercial oils the fatty acid composition can be estimated from the iodine value. Oils of the 3 experimental types of different species showed wide variations in fatty acid composition and represented many of the maximum and minimum values reported. So. Utiliz. Res. Dev. Div., ARS, USDA. ARS, USDA.  相似文献   

9.
The fatty acid composition and properties of six fractions of oil successively extracted from cottonseed meats has been investigated. The cyclopropenoid fatty acid concn increased regularly from 0.30–1.06%, a 3.5-fold increase. This suggests that the cyclopropenoid constituents of the oil in the seed are less accessible to the solvent. The linoleic acid concn decreased from 56.3–53.1% accounting for a slight reduction in iodine value (I.V.). The first two fractions had a markedly lower phosphatide content than the remaining fractions. Presented at the AOCS Meeting in Chicago, 1964. A laboratory of the So. Utiliz. Res. & Dev. Div., ARS, USDA.  相似文献   

10.
A total of 82 dietary fats sold on the Bulgarian market in the period 1995—2000 were analyzed. The samples included 68 table margarines (50 of which were imported), 10 frying fats (6 imported) and 4 salad dressings (all imported). A validated analytical method, thin‐layer chromatography‐AgNO3‐densitometry, was used. It enabled direct determination of all fatty acid groups, differing by degree of unsaturation and double bonds geometry. Low levels of trans fatty acids (TFA) down to 0.1% of the total for mono trans‐trienoic (Tcct) and mono trans‐dienoic (Dct), and down to 0.2% for trans‐monoenoic (Mt) were quantitated, with an error under 3% and a standard deviation of 0.1—1.5. The total content of TFA in table margarines varied from 0 to 26.9% with a mean value of 8.6 ± 7.2% for imported and 1.6 ± 3.4% for Bulgarian samples. Saturated fatty acids (SFA) content varied from 11.5 to 45.7%, with a mean value of 25.4 ± 5.7% for imported and 26.9 ± 5.2% for Bulgarian margarines. A general trend of lower levels of TFA and SFA in imported margarines was observed over the studied period. Additionally, the content of individual saturated fatty acids was determined by gasliquid chromatography in 37 of all studied samples.  相似文献   

11.
Any new crop for which there is a market, and which appears to be adapted to the region, would be attractive to replace nonprofitable traditional crops in Northwestern Argentina. Chia (Salvia hispanica L.) is especially attractive because it can be grown to produce oil for both food and industry. The fatty acids of chia oil are highly unsaturated, with their main components being linoleic (17–26%) and linolenic (50–57%) acids. Seeds from a chia population harvested in Catamarca were sown in five Northwestern Argentina locations. The oil from the chia seeds produced under these five field conditions was measured. Linolenic, linoleic, oleic, palmitic, and stearic fatty acid contents of the oil were determined by gas chromatographic analysis. The results showed variations in oil content, and the oleic, linoleic, and linolenic fatty acid concentrations of the oil were significantly affected by location.  相似文献   

12.
Lipids from five cultivars of highbush blueberries (Vaccinium corymbosum L.) were extracted and fractionated into neutral lipids (60–66%), glycolipids (20–22%) and phospholipids (14–18%). The major fatty acids in all fractions were palmitic (16∶0), oleic (18∶1), linoleic (18∶2), and linolenic (18∶3) acids. All lipid classes had a large concentration of C18 polyunsaturated acids (84–92%), indicating that blueberries are a rich source of linoleic and linolenic acids. Changes in the fatty acid composition of neutral lipids and phospholipids were not significantly different among the five cultivars, but significant differences were noted in the ratios of linoleic and linolenic acids in the glycolipids fraction.  相似文献   

13.
以中国野漆树、昭和福野漆树、伊吉野漆树等3种野漆树种籽为试材对象,利用索氏提取法和气相色谱-质谱联用法,测定了野漆树的含油率和脂肪酸成分。结果表明,(1)3种野漆树的含油率分别为12.37%,、6.46%、11.22%,差异极显著;(2)3种野漆树种籽油中脂肪酸成分至少有26种,其中亚油酸、油酸(E)、油酸(Z)、亚麻酸、棕榈油酸、棕榈酸、硬脂酸等7种脂肪酸的含量总和分别占测定到总脂肪酸含量的97.35%、97.92%、98.16%;(3)3种野漆树种籽油中不饱和脂肪酸与饱和脂肪酸差别较大,为73.08%~84.46%之间,最高差值达11.38%;(4)昭和和伊吉两个日本品种的野漆树与中国野漆树在12-羟基-油酸、环丙烯丁酸、亚麻酸(异构)、蓖麻醇酸(蓖麻油酸)、二十二烷酸、二十三烷酸、二十四烷酸、9-十八碳烯酸十四酯、月桂酸等9种脂肪酸中存在质的区别。  相似文献   

14.
The China-chestnuts (Sterculia monosperma, Ventenat) were examined for their fatty acid composition by gas liquid chromatography, infrared and nuclear magnetic resonance spectroscopy. The oil in nuts contained cyclopropene fatty acids (CPFA) determined as silver nitrate derivatives of their esters. The values (area %) for the major fatty acids as methyl esters were 23.47% C16:0, 1.25% C16:1, 2.56% C18:0, 24.89% C18:1, 18.24% C18:2, 5.40% dihydrosterculic, 3.21% C18:3 + C20:0 and 19.15% sterculic. The proportion of CPFA in the oil did not decrease upon cooking the nuts.  相似文献   

15.
The purpose of this study was to evaluate the trans fatty acid (TFA) composition and the tocopherol content in vegetable oils produced in Mexico. Sample oils were obtained from 18 different oil refining factories, which represent 72% of the total refineries in Mexico. Fatty acids and TFA isomers were determined by gas chromatography using a 100-m fused-silica capillary column (SP-2560). Tocopherol content was quantified by normal-phase high-performance liquid chromatography using an ultraviolet detector and a LiChrosorb Si60 column (25 cm). Results showed that 83% of the samples corresponded to soybean oil. Seventy-two percent of the oils analyzed showed TFA content higher than 1%. Upon comparing the tocopherol contents in some crude oils to their corresponding deodorized samples, a loss of 40–56% was found. The processing conditions should be carefully evaluated in order to reduce the loss of tocopherols and the formation of TFA during refining.  相似文献   

16.
Medium (8″ dia.) and small (4″) sized sunflower (EC 68415) heads of convex shape yielded seeds with more oil (>44%), unsaturation (I.V.M20) and linoleic acid (>48%) compared to big (12″) sized Both convex and flat shaped flower heads of medium size yielded seeds with more oil (>45%), unsaturation (I.V.>120) and linoleic acid (>48%) than did the concave shaped flower heads of medium size (39.9%, I.V. 112.6, 39.3%, respectively). The oil content, degree of unsaturation and linoleic acid content were thus found to vary with the size and shape of the sunflower head.  相似文献   

17.
Eight varieties of peanuts were grown under measured field conditions. Seed obtained at five successive harvest dates and separated into three maturity levels were analyzed for fatty acid composition of oil. Mature peanuts were mostly higher in stearic (18:0) and oleic (18:1) acids, and lower in linoleic (18:2), arachidic (20:0) and behenic (22:0) acids. Oleic-linoleic ratios, which are correlated with oil stability, were higher in mature peanuts. Presented at the AOCS Meeting, Houston, May 1971. Journal Paper No. 1115 of the Georgia Experiment Station and No. 2326 of the Oklahoma Agricultural Experiment Station.  相似文献   

18.
The fatty acid composition of 11 species of fish caught off the northeast coast of Australia was determined. No fatty acid profiles have been previously published for fish from this area nor for nine of these species. Although the percentage of polyunsaturated fatty acid (PUFA) was the same as the calculated average for Australian fish (42.3%), the percentage of n−3 fatty acids was lower (24.4±5.4% vs. 30.7±10.1%) and the n−6 fatty acids higher (16.5±4.5% vs. 11.2±5.9%), P<0.001 in each case. The major n−3 PUFA were docosahexaenoic (15.6 ±6.3%) and eicosapentaenoic acid (4.3±1.1%) while the major n−6 PUFA were arachidonic (8.3±3.2%) and n−6 docosatetraenoic acid (3.1±1.3%). The second-most abundant class of fatty acid was the saturates (31.6±3.5%) while the monounsaturates accounted for 17.4±4.3% of the total fatty acids. The monounsaturate with the highest concentration was octadecenoic acid (11.8±2.6%). There was a positive correlation between the total lipid content and saturated and monounsaturated fatty acids (r=0.675 and 0.567, respectively) and a negative correlation between the total lipid content and PUFA (r=0.774).  相似文献   

19.
Phospholipid (PL) fatty acid composition and stereospecific distribution of 25 genetically modified soybean lines with a wide range of compositions were determined by gas chromatography and phospholipase A2 hydrolysis. Pl contained an average of 55.3% phosphatidylcholine, 26.3% phosphatidylethanolamine, and 18.4% phosphatidylinositol. PL class proportions were affected by changes in overall fatty acid composition. PL fatty acid composition changed with oil fatty acid modification, especially for palmitate, stearate, and linolenate. Stereospecific analysis showed that saturated fatty acids were primarily located at the sn-1 position of all PL, and changes of the saturates in PL were largely reflected on this position. Oleate was distributed relatively equally between the sn-1 and sn-2 positions. Linoleate was much more concentrated on sn-2 than on sn-1 position for all PL. Linolenate was distributed relatively equally at low concentration but preferred sn-2 position at high concentration.  相似文献   

20.
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