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1.
Analyses of the seed oil of 43Linum species showed great variability in fatty acid composition. The species can be grouped in two broad categories on the basis of seed oil composition: 1) Those with high linolenic, low linoleic and low oleic acid content, and 2) Those with high linoleic, low linolenic and low oleic acid content. A positive correlation was observed between iodine value and linolenic acid content, and a negative correlation between linolenic and linoleic acid content. There was no correlation between fatty acid composition and chronosome number. No. 1722, University of California Citrus Research Center and Agriculture Experiment Station, Riverside, California.  相似文献   

2.
In field trials at Giza in 1986–1987, cotton cv. Giza 75 was sown at 166,000, 222,000 and 333,000 plants/ha and given foliar applications of 0, 250, 500 and 750 ppm Cycocel (chlormequat) or Alar (daminozide). As plant density increased, there was a decrease in cottonseed yield/ha, seed index, seed protein content, oil and protein yields/ha, oil refractive index, iodine value, unsaponifiable matter and unsaturated fatty acids (myristoleic, oleic and linoleic). In contrast, as plant density increased, there was an increase in oil acid value, saponification value and saturated fatty acids (caprylic, capric, lauric, tridecylic, myristic, palmitic and stearic). Application of Cycocel or Alar increased cottonseed yield/ha, seed index, seed protein content and oil and protein yield/ha, oil refractive index, iodine value, unsaponifiable matter and unsaturated fatty acids. However, there was a decrease in oil acid value and saponification value. There were no differences among application rates of either chemical on cottonseed yield/ha. The highest oil and protein yield/ha was observed with Cycocel applied at 750 ppm, followed by Alar at 250 ppm. Applying Cycocel at 250 ppm gave the highest oil refractive index and unsaponifiable matter, and the lowest acid value. Application of Alar at 250 ppm gave the highest oil iodine value and the lowest saponification value, and also at 250 or 500 ppm gave the highest oil unsaturated fatty acid composition. Interaction was positive between plant density, Cycocel and Alar and affected cottonseed yield/ha. The 166,000 plants/ha and application of Cycocel at 750 and Alar at 250 ppm are recommended for the improvement of cottonseed yield and quality.  相似文献   

3.
Tall oil fatty acids have been fractionated into 80–90% oleic acid, and 60–80% linoleic acid fractions, by precipitation of the oleic acid as acid soap from polar solvents. Sodium and potassium acid soaps are equally effective, but ammonium acid soaps require lower operating temperatures. The choice of solvent is not critical as regards degree of separation, but technically attractive filtration rates have been obtained only with methanol and acetone. Acidulation gives colorless oleic acid of very low rosin acid and unsaponifiable content, but with 5–10% of conjugated linoleic acid.  相似文献   

4.
In Austria pumpkins are grown primarily for the production of pumpkin seeds that can be used for eating or the production of salad oil. Pumpkin seed oil is dark green and its fatty acid composition consists typically of linoleic acid and oleic acid as the dominant fatty acids. The saturated fatty acids palmitic and stearic acid occur at lower levels. The samples for this study were taken from a breeding program that intends to increase the seed and oil productivity. 15 samples with different contents of linoleic acid (40—57%) and vitamin E (100—600 μg/g) were selected. The stability of the oil was measured in a Rancimat that oxidizes the oil at 120 �C and measures the induction time that is needed for the oxidation. The correlation analysis showed that only the ratio of linoleic acid to oleic acid had a significant influence on the oxidative stability of the oil. Vitamin E did not show any correlation. When α‐tocopherol was added to the oil a strong pro‐oxidative effect was observed.  相似文献   

5.
Rice bran oil and double fractionated palm olein (DF palm olein) were heated at 180 C for 50 hr to measure lipid deterioration in the oils. Free fatty acid content of both oils increased during heating; however, iodine value and smoke point decreased. Solid fat contents of both oils were unaffected by heating time. Cloud point of rice bran oil was much lower than that of palm olein. Color of oils changed gradually to dark brown from light yellow with increased heating time. Absolute content of polyunsaturated fatty acid, such as linoleic acid, reduced more than that of monounsaturated fatty acid, such as oleic acid, in both oils. In both oils, iodine value correlated very well with linoleic acid content, with correlation coefficient higher than 0.96.  相似文献   

6.
The jatropha oil was extracted from the jatropha seeds collected from different origins viz., Malaysia, Indonesia and Thailand. The physicochemical properties such as density, viscosity, percentage free fatty acid (FFA), iodine value, saponification value and peroxide value of the extracted jatropha seed oil were evaluated. The evaluation of fatty acid composition using gas chromatography (GC) revealed that, oleic (42.4–48.8%) and linoleic acid (28.8–34.6%) are the dominant fatty acids present in the jatropha seed oil. The saturated fatty acids such as palmitic and stearic acid lie in the range 13.25–14.5 and 7–7.7%, respectively. The observed major triacylglycerol (TAG) composition was OOL (22.94–25.75%) and OLL (15.52–20.77%).  相似文献   

7.
Oil content, fatty acid composition and karanjin content were studied in developing pongamia seeds, at intervals of 3?weeks from 30?weeks after flowering up to 42?weeks. Three marked stages in seed development were observed at the early green pod stage, the middle half brown stage and the late dark brown stage. Significant variation in seed biomass, pod and seed characteristics were observed. A significant (P?<?0.01) decrease in the moisture content of the seeds was observed during seed development. The oil content gradually increased from 32.06 to 36.53?% as the seed matured. A significant variation in fatty acid composition was detected across all stages of seed development. Palmitic acid (16:0) content marginally decreased from 11.81 to 10.18?%, while stearic acid (18:0) and linolenic acid (18:3) remained constant at all stages of seed maturity. A steady increase in oleic acid (18:1) content from 38.11 to 49.11?% was observed, while the linoleic acid (18:2) content decreased from 30.14 to 18.85?%. The iodine value increased, while the saponification number of oil decreased during seed development. The increase in karanjin content was steady. Seeds harvested after 42?week after flowering yielded the maximum oil with high oleic acid content which could be suitable for biodiesel production.  相似文献   

8.
The physicochemical characteristics and FA compositions were determined for refined-bleached-deodorized (RBD) high-palmitic acid solin (HPS) oil, RBD solin oil, and degummed linseed oil. The predominant FA in HPS oil were palmitic (16.6%), palmitoleic (1.4%), stearic (2.5%), oleic (11.3%), linoleic (63.7%), and linolenic (3.4%). HPS oil was substantially higher in palmitic acid than either solin oil or linseed oil, and similar to solin oil in linolenic acid content. HPS, solin, and linseed oils exhibited similar sterol and tocopherol profiles. The physicochemical characteristics of the three oils (iodine value, saponification value, m.p., density, specific gravity, viscosity, PV, FFA content, color) reflected their FA profiles and degree of refinement. During hydrogenation of HPS oil, the proportion of saturated FA (palmitic and stearic) increased, and that of unsaturated FA (oleic, linoleic, and linolenic) decreased as the iodine value declined. This resulted in an inverse linear relationship between m.p. and iodine value. Hydrogenation also generated trans FA. The proportion of trans FA was inversely related to iodine value in partially hydrogenated samples. Fully hydrogenated HPS oil (i.e., HPS stearine, iodine value <5) was devoid of trans FA.  相似文献   

9.
Seed oil content of globe artichoke and its composition were assessed under three irrigation regimes, including irrigation at 20, 50, and 80 % depletion of soil available water. Water deficit affected the phenological characteristics, amount and the quality of the oil as well as the phenolics and antioxidant activity of the leaves and capitula. The seed oil content ranged from 18.7 % in 80 % to 22.8 % in 20 % treatment. The fatty acid composition of oil was determined using gas chromatography (GC). The predominant fatty acids in the oil were linoleic (51.68 %), oleic (34.22 %), palmitic (9.94 %), and stearic (3.58 %). Water deficit leads to reduced oil content, linoleic acid, the unsaturated/saturated fatty acid ratio and the iodine value. On the other hand, some other fatty acids such as palmitic and oleic acid and also the ratio of oleic/linoleic acid were elevated due to water deficit. Higher antioxidant activity was observed in capitula (IC50 = 222.6 μg ml?1) in comparison to the leaves (IC50 = 285.8 μg ml?1). Finally, the severe drought stress condition caused to gain higher oil stability, while the highest seed oil content and unsaturated fatty acids in the oil was obtained in non‐stress condition. Moreover, high phenolics, flavonoids and antioxidant activity as well as appreciable dry matter content were obtained in the moderate water stress condition.  相似文献   

10.
Summary RESULTS of analysis of 148 linseed oil samples are summarized. When the constituent fat acid glycerides are plotted against the iodine number the points fall close to a straight line in the cases of saturated acids, oleic acid and linolenic acid. In the case of linoleic acid, however, the points were so dispersed that no significant relationship to the iodine number was apparent. Correlation coefficients between iodine number and the fat acids were: Linolenic, +.97: oleic, −.94; saturated, −.80; and linoleic. −.27. It is possible to estimate within limits the amount of linolenic, oleic and saturated acids in linseed oil by applying equations where the iodine number is the only variable. In the case of linoleic acid, however, the standard deviation along the regression line is almost equal to the standard deviation from the mean. Real differences in composition which are independent of the iodine number exist, however, because the dispersion of the points along the regression lines is greater than would result from errors of precision in the analyses. Presented before the meeting of the American Chemical Society at Cleveland, Ohio, April, 1944. Published by permission of the Director, N. Dak. Agr. Expt. Station. This work was carried out under Purnell project 95, “The Chemistry of Flaxseed”.  相似文献   

11.
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   

12.
The oil content, fatty acid and sterol compositions and other parameters of pistachio nut (Pistacia vera L.) samples corresponding to five different varieties, all cultivated in Turkey were determined. Mean values were 59.69 ± 1.80% for fat content, 0.9143 ± 0.006 for specific gravity of the oil, 1.4693 ± 0.004 for refractive index, 94.23 ± 1.510 for iodine value, and 188.2 ± 3.80 for saponification value. Fatty acids identified in the oil samples were palmitic, palmitoleic, stearic, oleic, and linoleic acids with oleic acid as the dominant fatty acid (68.78 ± 2.05%). Halebi variety had the highest level of oleic acid among the varieties studied. The sterols isolated from the unsaponifiable fraction were campesterol, stigmasterol, β-sitosterol, and Δ5-avenasterol with β-sitosterol as the major constituent (84.95 ± 2.80%). Higher levels of β-sitosterol were found in Kιrmιzι variety. The high level of oil, oleic acid and β-sitosterol content was found in all the varieties studied. Fat content, iodine value, palmitic acid and oleic acid content significantly differed between varieties.  相似文献   

13.
The present investigation was conducted to determine if foliar-applied trehalose (an osmoprotectant) could ameliorate the adverse effects of water shortage on maize seed oil composition and oil antioxidant potential. Drought stress significantly reduced the seed oil but increased oleic acid and linolenic acid contents of the oil with a concomitant decrease in linoleic acid content, which resulted in an increased oil oleic/linoleic ratio in both maize cultivars. Water stress also increased the seed oil α- γ- δ- and total tocopherols and flavonoids of both maize cultivars, however, oil phenolic content and oil antioxidant activity decreased. Exogenously applied trehalose positively influenced seed composition of both maize cultivars under non-stress and water stress conditions. Exogenous application of trehalose further increased the oil oleic and linolenic acid contents with a subsequent decrease in linoleic acid. Furthermore, exogenous application of trehalose increased the oil antioxidant activity in terms of oil DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity with an increase in oil tocopherols, total flavonoids and total phenolics contents.  相似文献   

14.
A comparison of iodine values showed that the degree of saturation of tea seed oil (Lahjan variety) was intermediate between the oils of sunflowerseed (Fars variety) and olive (Gilezeytoon variety), and the saponification values of these three oils were similar. Tea seed oil consisted of 56% oleic acid (C18∶1), 22% linoleic acid (C18∶2), 0.3% linolenic acid (C18∶3), and therefore, on the basis of oleic acid, occupied a place between sunflower and olive oil. In studies at 63°C, the shelf life of tea seed oil was higher than that of sunflower oil and similar to olive oil. Tea seed oil was found to have a natural antioxidant effect, and it enhanced the shelf life of sunflower oil at a 5% level. In this study, tea seed oil was found to be a stable oil, to have suitable nutritional properties (high-oleic, medium-linoleic, and lowlinolenic acid contents), and to be useful in human foods.  相似文献   

15.
The variation in oil content, oil yield and fatty acid compositions of 103 sesame landraces was investigated. The landraces varied widely in their oil quantity and quality. The oil content varied between 41.3 and 62.7%, the average being 53.3%. The percentage content of linoleic, oleic, palmitic and stearic acids in the seed oil ranged between 40.7–49.3, 29.3–41.4, 8.0–10.3 and 2.1–4.8%, respectively. Linolenic and arachidic acids were the minor constituents of the sesame oil. Linoleic and oleic acids were the major fatty acids of sesame with average values of 45.7 and 37.2%, respectively. The total means of oleic and linoleic acids as unsaturated fatty acids of sesame were about 83% which increases the suitability of the sesame oil for human consumption. The superiority of the collection was observed in oil content. The oil content of a few accessions was above 60%, proving claims that some varieties of sesame can reach up to 63% in oil content. The accessions with the highest oil content were relatively richer in the linoleic acid content while there were some landraces in which linoleic and oleic acid contents were in a proportion of almost 1:1. The results obtained in this study provide useful background information for developing new cultivars with a high oil content and different fatty acid compositions. Several accessions could be used as parental lines in breeding programmes aiming to increase sesame oil quantity and quality.  相似文献   

16.
Indian wood apple seed (Feronia elephantum Correa) constituting 6% (dry weight basis) of the fruit, contains 34% oil and 28% protein. The kernel comprises 62% of the seed. The oil is yellow with an iodine value 131, saponification value 192, unsaponifiable matter 1%. Fatty acid profile of oil by GLC is: palmitic 19.3, stearic 7.3, oleic 27.2, linoleic 19.8 and linolenic 26.4%.  相似文献   

17.
Camellia seed oil with high nutritional value is widely used in southern China and southeastern Asia for cooking. Due to the high price of camellia seed oil, fraudulent traders blended the oil with inexpensive oils to increase profits. In this paper, a new method was introduced to detect the adulteration of camellia seed oil with soybean oil by GC–MS with consideration of a parameter which was defined by the total content of oleic and linoleic acid, the oleic to linoleic acid ratio and the content of linolenic acid. Oils samples were prepared by blending pure camellia seed oil with pure soybean oil at levels from 1 to 50 %. Fatty acids esterified by TMSH and TBME in seconds were separated and identified by GC–MS. The detection limit of adulteration was as low as 5 %, and even much lower than 5 % for most kinds of camellia seed oil, which was lower than those measured by other methods. All the results indicated that this simple, accurate and rapid method can also be recommended for the authentication of olive oil with some modification.  相似文献   

18.
Seed of Guindilla (Valenzuela trinervis Bert.) and its oil were characterized. On a dry weight basis, the seed consists of 56% hull and seed coat and 44% cotyledon, containing about 67.0% lipids. The main fatty acids are: 62.3% oleic, 12.9% gadoleic, 10.1% linoleic and 9.6% palmitic. Physical properties of oil, expressed by hand press, include: melting point, −6 to −2 C; iodine value, 75.1; saponification value, 192; and unsaponifiable matter, 0.8%.  相似文献   

19.
A germplasm collection of 33 entries comprising 22 sesame (Sesamum indicum L.) cultivars, 4 landraces of S. mulayanum and 7 other accessions of 4 wild species were analyzed for the fatty acid compositions of their seed oil. The entries varied widely in their fatty acid compositions. The percentage content of oleic, linoleic, palmitic and erucic acids ranged between 36.7–52.4, 30.4–51.6, 9.1–14.8 and 0.0–8.0, respectively. Linolenic and arachidonic acids were the minor constituents but varied widely in wild species. Oleic and linoleic were the major fatty acids with mean values of 45.9 and 40.5%, respectively and the mean of their combined values was 86.4%. The polyunsaturated fatty acid (PUFA) compositions ranged from 30.9 to 52.5% showing high variation in PUFA in the germplasm. Linoleic acid content was very high in one landrace (47.8) and one accession each of three wild species, S. mulayanum (49.3), S. malabaricum (48.2) and S. radiatum (51.6%). Use of fatty acid ratios to estimate the efficiency of biosynthetic pathways resulted in high oleic and low linoleic desaturation ratios and consequently high linoleic and very low linolenic acid contents in seed oil. The results of this study provided useful background information on the germplasm and also identified a few accessions having high linoleic acid which can be used for developing cultivars with desirable fatty acid compositions.  相似文献   

20.
The fatty acid composition and tocopherol content of sunflower seeds from experimental plantings in Japan were determined. Lipid content of sunflower seed was almost the same irrespective of the variety and the average lipid content was 38.8%. The saturated fatty acids were low and the combined percentage of linoleic acid and oleic acid was ca. 90%. The ratio of oleic acid to linoleic acid largely varied with the planting location and date. There was a strong correlation between the percentage of linoleic acid or oleic acid and the temperature during maturation of seed. The sunflower seed contained predominantly α-tocopherol and small amounts ofβ-,γ- and δ-tocopherol. There was no correlation between a-tocopherol content and the percentage of linoleic acid.  相似文献   

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