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1.
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   

2.
The objective of this study was to demonstrate that changing the fatty acid composition of bovine adipose tissue concurrently changed (i) proportions of triacylglycerol species, (ii) fatty acid composition of triacylglycerol species, and (iii) positional distribution of the component fatty acids of the triacylglycerol species. To achieve this, we took advantage of adipose tissue lipids, from cattle fed in Australia and Japan, that varied widely in fatty acid composition and melting points. Treatment groups produced in Australia were cattle fed: a cornbased diet (MUFA1); a grain-based diet containing whole cottonseed (SFA); a grain-based diet containing protected cottonseed oil (PUFA); and a grain-based diet that resulted in high contents of trans fatty acids (TFA). Treatment groups produced in Japan (MUFA2 and MUFA3) were diets of unknown composition fed for over 300 d. The MUFA1, MUFA2, and MUFA3 samples all were rich in monounsaturated fatty acids, varying only in the proportions of the individual monounsaturates. The SFA, PUFA, and TFA samples had relatively high concentrations of stearic acid (18:0), PUFA, and TFA, respectively. Slip points (indicative of melting points) were 45.1, 41.5, 38.5, 30.7, 28.4, and 22.8°C, for the SFA, TFA, PUFA, MUFA1, MUFA2, and MUFA3 groups, respectively (P<0.05). Triacylglycerols were separated by high-performance liquid chromatography on a silver nitrate-impregnated column into sn-1,2,3-saturated fatty acid triacylglycerol (SSS); [triacylglycerols containing two saturated acids and one trans-monounsaturated fatty acid (SSMt sn-positions unknown)]; sn-1-saturated, 2-monounsaturated, 3-saturated triacylglycerol (SMS); sn-1-saturated, 2-monounsaturated, 3-trans-monounsaturated triacylglycerol (SMMt); sn-1-saturated, 2,3-monounsaturated fatty acid triacylglycerol (SMM); sn-1-saturated, 2-polyunsaturated, 3-trans-monounsaturated triacylglycerol; sn-1,2,3-monounsaturated fatty acid triacylglycerol (MMM); and sn-1-saturated, 2-polyunsaturated, 3-monounsaturated triacylglycerol. Fatty acid methyl esters of each triacylglycerol species also were determined, and further analysis indicated sn-2, and sn-1/3 positions. As the percentage oleic acid increased in the total lipid extract, the proportions of SMM and MMM increased (e.g., from 31.4 and 2.4% in the SFA group to 55.4 and 17.8% in the MUFA3 group). The elevated 18:0 in the SFA group (26%) was reflected in increased percentages of SSS and SSM, and caused an increase in the proportion of 18:0 in all triacylglycerol species relative to the other treatment groups. The percentage of 18:0 in the sn-1/3 positions was elevated markedly in the SMS fraction of the SFA group (to 44%); this would account for the high melting point of the fat of these animals. We conclude that long-term feeding of cattle is sufficient to produce significant alterations in fatty acid composition in bovine adipose tissue. Alterations in the fatty acid composition of bovine adipose tissue changed both the distribution and the composition of the triacylglycerol species, which, in turn, accounted for marked differences in melting points among treatment groups.  相似文献   

3.
Wild almond Amygdalus scoparia is a very fruitful tree that is spread over an extensive region of Iran. Considering its high quality oil, the development of clean extraction processes based on the use of compressed fluids is encouraged. In this study, the main factors involved in supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE) of wild almond have been optimized by using two different experimental designs and considering the oil extraction yield as a response variable; effects of time, temperature, pressure, and use of co‐solvents were studied for SFE while effects of time, temperature and type of solvent were evaluated for PLE. Results showed that the maximum oil yield using supercritical carbon dioxide was 42 %, obtained under the following conditions: extraction temperature, 40 °C; extraction pressure, 40 MPa; and 10 % ethanol as co‐solvent. The optimum extraction yield for PLE was 55 %, which was achieved using ethanol as solvent at 150 °C for 20 min. Lipidomic analysis revealed that the amount of oleic acid in the oil extracted by SFE was higher than those obtained by using other classical procedures. In addition, triacylglycerols constituted more than 98 % of the extracted oils.  相似文献   

4.
Wild almond (Amygdalus scoparia) oil is rich in oleic acid and, considering both nutritional and stability points of view, it can be utilized for future food applications. In the current study, acid degumming was investigated based on a method by response surface methodology using four degumming parameters, namely the amount of phosphoric acid (0.0–0.2%, w/w), the amount of water (1.0–5.0%, w/w), degumming temperature (30–70 °C), and degumming time (10–50 min). Optimum conditions for the minimum phosphorus level in the oil were found to be 0.15% phosphoric acid, 3.0% water, 40 °C degumming temperature, and 28 min degumming time, resulting in an almost complete removal of phosphorus. The final degummed wild almond oil had less than 1 mg kg−1 phosphorus (reduced from an original value of 206 mg kg−1). The experimental value of phosphorus reduction at optimum conditions agreed well with that predicted by the model. Peroxide value, anisidine value, iron, copper, and lead contents, phytosterols, unsaponifiable matter, and color of the oil decreased significantly during the degumming process; however, the fatty acid composition did not change. Also, degumming did not significantly impact the free fatty acid level, refractive index, density, iodine value, and the saponification value of the oil. However, tocopherols and the oxidative stability of the oil increased during degumming. Crude wild almond oil contained a trace level of amygdalin, which was completely eliminated during the degumming process.  相似文献   

5.
Lipid composition was studied in different white muscle zones (ventral, dorsal and tail) of wild and farmed blackspot seabream (Pagellus bogaraveo). The study was complemented by moisture, trimethylamine oxide (TMAO) and trace mineral determinations. Farmed fish muscle showed higher lipid and triacylglycerol contents, but lower values for moisture, TMAO and α‐tocopherol than its wild fish counterpart; no differences could be observed between both kinds of fish for the phospholipid, sterol and free fatty acid contents. When compared to wild fish, a higher saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acid (PUFA) content was obtained in farmed fish, while lower values could be observed for the n‐3/n‐6 and 22:6n‐3/20:5n‐3 fatty acid ratios. Most minerals analysed (Cu, Fe, Mn, Se and Zn) showed higher mean values in farmed fish muscle, except for Ca and Mg which provided higher mean contents in wild fish. Concerning the muscle site comparison, greater SFA, MUFA and PUFA contents could be detected in the dorsal zone than in the two other locations both for farmed and wild fish, in accordance with a higher mean lipid content found at this site. Finally, the tail zone showed higher TMAO values than the two other locations.  相似文献   

6.
Cashew nut oils, extracted from raw and roasted whole cashew nuts, were examined for their fatty acid composition, color change and oxidative stability. Fatty acids were analyzed using gas chromatography, and a spectrophotometric method was used to determine the color changes of the resultant oils. Oxidative stability was determined under accelerated oxidation conditions by employing conjugated diene (CD) and thiobarbituric acid reactive substances (TBARS) assays. The contents of monounsaturated (MUFA), polyunsaturated (PUFA) and saturated (SAFA) fatty acids were 61, 17 and 21%, respectively. Oleic acid was the major MUFA whereas linoleic acid was the main PUFA present in cashew nut oils. Oxidative stability of the oil as determined by CD values after 72 h of storage under Schall oven condition at 60 °C was 1.08 and 0.65 for the raw and high temperature roasted cashew nut, respectively. The TBARS values, expressed as malondialdehyde equivalents decreased with increasing roasting temperature. Thus roasting of whole cashew nuts improved the oxidative stability of the resultant nut oils.  相似文献   

7.
The seeds of 8 plant species of Mimosaceae were studied for their fat and protein contents and fatty acid and mineral compositions. The oil fromEntada phaseoloides contained 14 newly identified acids in addition to 8 previously reported. Six seed oils were rich in oleic and linoleic acid as the sum of 18:1 and 18:2 ranged from 64.4–78.5%.  相似文献   

8.
Seed samples of 54 species of wild Cruciferae were newly collected from natural populations of the west Mediterranean and adjacent areas in a search for “new” oil crops. Oil contents and fatty acid compositions were determined simultaneously by gas liquid chromatography using methyl heptadecanoate as the internal standard. The study revealed large variations in oil content (6–48.8%), oleic acid (5–31.3%), linoleic acid (2–24.8%), linolenic acid (1.7–64.1%), and erucic acid (0–55.1%). Correlation coefficients between component fatty acids inter se and oil content were determined separately for all species, the tribe Brassiceae, and the genusBrassica. The promising species identified are being studied further.  相似文献   

9.
Seed oil ofEuphorbia lagascae Spreng. contains 57% ofcis-12,13-epoxy-cis-9-octadecenoic (vernolic) acid. The amt of trivernolin in the glycerides of this species indicates random or restricted random distribution of the vernolic acid. Seed from 57 additional species in the Euphorbiaceae were analyzed for oil and protein contents and also for fatty acid composition of the oils. Iodine values (I.V.) of the oils ranged from 87–221. Among these oils, samples were encountered with as much as 76% linolenic, 77% linoleic or 84% oleic acid. Presented at the AOCS in New Orleans, 1964. A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, USDA. ARS, USDA.  相似文献   

10.
Declarations of the total content of trans fatty acids (FA) and saturated FA (SFA) are mandatory on food labels in the US and Canada. Gas chromatography (GC) has been the method of choice for the determination of FA composition. However, GC is time consuming and requires conversion of fats and oils to their FA methyl esters. In the present study, a recently published Fourier transform near-infrared (FT-NIR) spectroscopic procedure was applied to the rapid (<5 min) determination of total SFA, monounsaturated FA (MUFA), polyunsaturated FA (PUFA), and trans FA contents of 30 commercially available edible fats and oils. Good agreement was obtained between the GC and FT-NIR methods for the determination of total SFA, MUFA, and PUFA contents. Differences between the two methods were apparent for the determination of trans fat at trans fat levels <2 % of total fat. The analytical determinations of total SFA, MUFA, and PUFA contents for many of the oils examined differed from the respective values declared on the product labels. Our findings demonstrate that the FT-NIR procedure serves as a suitable alternative method for the rapid determination of total SFA, MUFA, PUFA and trans FA contents of neat vegetable oils.  相似文献   

11.
The aims of this study were to compare three treatments in the chemical hydrolysis reaction of bleached oil from carp (Cyprinus carpio) heads and to obtain polyunsaturated fatty acid concentrates by urea complexation. The three treatments were carried out with different oil:ethanol molar ratios. In the treatment with a 1:39 molar ratio, a higher yield of free fatty acids was found. These fatty acids were submitted to urea complexation (−10 °C for 20 h, and urea–fatty acid ratio of 4.5–1). There was a 31.4% increase in monounsaturated and polyunsaturated fatty acids (MUFA and PUFA) content and a 75% decrease in saturated fatty acids (SAF) content. An increase of 85.4% in the EPA + DHA content was found. The non-urea complexing fraction can be considered a rich source of MUFA and PUFA with a total amount of 88.9%.  相似文献   

12.
The effects of different heat treatment methods on the extraction yield of oil and the amygdalin contents of the wild almond meal and oil were investigated. When using hexane as a solvent for the extraction, oil yield and amygdalin contents of the extracted oils increased by increasing the applied temperature as the pretreatment (46.1–51.6%, w/w, for oil yield and 26–49 mg/100 mL oil for the amygdalin content). When using mechanical oil extraction, hot-press resulted in higher oil yield (23.2%) than did the cold-press (15.6%) but the amygdalin levels of the extracted oils were not significantly different (12.8–12.9 mg/100 mL oil). Autoclaving ground wild almond and hot-press resulted in a significant increase in the peroxide and acid values of the oils. Investigation of fatty acid profiles of different samples showed that heat treatment and extraction method in this study did not impact the fatty acid profiles of the extracted oils.  相似文献   

13.
The fatty acid (FA) profiles of edible muscle of selected commercially important freshwater and marine fish species from Turkey were investigated. The fatty acid compositions of freshwater fish species were 23.00–29.60% saturated (SFA), 25.70–36.50% monounsaturated (MUFAs), and 26.59–31.92% polyunsaturated acids (PUFAs), whereas the fatty acid compositions of marine fish consisted of 21.08–36.90% (SFA), 18.03–51.45% MUFAs, and 20.92–53.17% PUFAs. There was a wide variation and significant (P < 0.05) differences among the fatty acid profiles of the freshwater and marine fish samples, including differences in the SFA, MUFA, PUFA, EPA, DHA, DHA/EPA, total n-3 PFAs, total n-6 PUFAs and n-3/n-6 values. In addition, the cheap marine fish species such as anchovy and European pilchard, bogue are better dietary sources of n-3 PUFAs than more expensive species such as bluefish, Atlantic mackerel, sea bream and sea bass. Through the application of two multivariate statistical methods, Principal Component and Hierarchical Analysis, fish species from Turkey waters were classified according to the geographical locations categorized in terms of fatty acid profiles. Clustering by fish species also gave rise to defined groups.  相似文献   

14.
In this study, the effects of temperature on the fatty acids profile and the effects of temperature on the degree of unsaturation of fatty acids of Oreochromis niloticus were investigated. The analysis was performed by gas chromatography. The study showed that there were large temperature variations (10.0–32.0°C) during the study period (January–December). The highest crude fat content was found in January (3380 mg/100 g) and the lowest in June (2050 mg/100 g). The fatty acids profile showed significantly different diversity (p < 0.05). Total saturated fatty acid (∑SFA) content ranged from 409.54 to 1297.61 mg/100 g, monounsaturated fatty acid (∑MUFA) from 207.68 to 665.81 mg/100 g, and polyunsaturated fatty acid (∑PUFA) from 175.12 to 972.23 mg/100 g. The ∑MUFA and ∑PUFA concentrations were highest in January and lowest in June, and the ∑SFA concentration was lowest in January and highest in June. EPA and DHA contents were highest in January (198.96 mg/100 g) and lowest in June (48.76 mg/100 g). The contents of omega-3 (653.17 mg/100 g) and omega-6 fatty acids (252.54 mg/100 g) were highest in January and lowest in June (ω-3; 106.43 and ω-6; 60.91 mg/100 g). It concluded that the degree of unsaturation of fatty acids increases with decreasing temperature. In this study, the nutritional quality of the FAs profile was assessed using lipid quality indices. The indices indicating dietary quality of lipids by their values: Atherogenic index (0.47), thrombogenic index (0.38), hypocholesterolemic to hypercholesterolemic (3.00), meat fat quality (6.78), ω6/ω3 ratio (0.39), PUFA/SFA (2.37), MUFA/SFA (1.62), PUFA/MUFA (1.46), and PUFA + MUFA/SFA (3.99). These values are within the recommended range, indicating that the lipid profile of O. niloticus has high nutritional quality, which can be further improved by harvesting the fish during the winter season. Due to the nutritional importance of O. niloticus, the culture of this species could have significant interest to the people of Karachi, especially the coastal communities. To promote the nutritional diet in local population, the government should support the aquaculture of Nile tilapia.  相似文献   

15.
Mustonen AM  Asikainen J  Aho J  Nieminen P 《Lipids》2007,42(12):1155-1167
Previous studies on laboratory rodents, rabbits and humans have demonstrated that fatty acid (FA) mobilization from white adipose tissue (WAT) is selective and its efficiency is related to FA structure. Selective FA mobilization was also documented in a carnivore, the farmed raccoon dog (Nyctereutes procyonoides), fasted for 8 weeks. The present study explored whether similar selectivity of FA mobilization was manifested in wild mammals experiencing seasonal food scarcity and abundance. Fractional mobilization from and incorporation into WAT of a wide spectrum of FA were studied by gas–liquid chromatography from the subcutaneous WAT of free-ranging raccoon dogs with the same individuals sampled in consecutive seasons. The wintertime FA mobilization was selective and mostly confirmed the patterns of FA release in captivity. Mobilization correlated inversely with the FA chain length but increased with unsaturation and when the first double bond was located closer to the methyl end. 18–20C n-3 polyunsaturated FA (PUFA) and 14–17C monounsaturated FA (MUFA) were preferentially mobilized while 19–24C saturated FA and MUFA were preserved during wintering. The summertime FA incorporation correlated inversely with the chain length and increased with unsaturation and in MUFA and PUFA with double bonds closer to the methyl end. The principles of selective FA mobilization were valid in wild mammals. FA incorporation was also selective and reversed the wintertime losses of the preferably mobilized FA.  相似文献   

16.
Blending and interesterification of cold‐pressed oil from commercially available niger (Guizotia abyssinica (L.f.) Cass.) seeds was performed to improve its stability. The fatty acid composition of cold‐pressed niger seed oil (NSO) revealed that it contained a huge amount of polyunsaturated linoleic acid (69.2 %). NSO being rich in polyunsaturated fatty acids (PUFA) was susceptible to oxidation and hence was blended with saturated fatty acid (SFA) rich coconut oil (CNO) and monounsaturated fatty acid (MUFA) rich olive–pomace oil (OO) to enhance its stability. CNO contained a total of 91.3 % of SFA, while OO had oleic acid, C18:1 (74.3 %) as MUFA. Two blends of NSO with CNO and OO, i.e. NSO + CNO(B) and NSO + OO(B), were prepared in the ratio of 1:1. The blends were further interesterified using the lipase enzyme from Rhizomucor meihei and interesterified oils, i.e. NSO + CNO(I) and NSO + OO(I), were obtained. The oxidative stability of the oils was evaluated by incubating them at 37 °C and 55 % relative humidity (RH) for a period of 45 days. The peroxide values of NSO + CNO(B), NSO + OO(B), NSO + CNO(I) and NSO + OO(I) showed a reduction by 53.3, 42.6, 65.3 and 55.4 %, respectively, while the conjugated diene values showed a reduction by 75.0, 66.9, 76.7 and 75.3 %, respectively, as compared to NSO during the incubation period. This is probably the first report on the stability improvement of niger seed oil through blending and interesterification.  相似文献   

17.
The lack of uniformity of analytical techniques employed for quantification of fatty acids led to the successful implementation of a rapid transesterification method using tetramethylammonium hydroxide to determine and compare the total fatty acid content of almond, pecan and macadamia oils. Palmitic, oleic and linoleic acids comprised the largest part of the total fatty acid content in almond and pecan oils. Although oleic acid was also the main constituent of macadamia oil, its concentration was substantially lower than in the other oils.  相似文献   

18.
The objective of this study was to improve the content of docosahexaenoic acid (DHA) and obtain the blended oils used for different cooking methods (steaming, boiling, and stir-frying) by blending 0%–15% DHA algal oil into soybean oil. It was shown that the addition of DHA algal oil increased saturated fatty acid (SFA) (1.57%) but decreased monounsaturated fatty acid (MUFA) (0.76%) and polyunsaturated fatty acid (PUFA) (0.68%). Various cooking methods significantly changed the fatty acid (FA) compositions. Steaming is a more effective way to prevent DHA loss and the production of trans-fatty acid than boiling and stir-frying. Besides, a positive result from free fatty acid (FFA) and peroxide value also demonstrated that steaming was a better way to protect oils. Overall, the soybean oil blended with 3% DHA algal oil with better oxidative stability and could be recommended for daily application by steaming.  相似文献   

19.
Roasting enhances sensory quality of wild almonds (Amygdalus scoparia). The aim of the study was to evaluate the use of microwaves (480 W for 3 or 4 min) in roasting of wild almonds in comparison with traditional Spanish (165 °C for 20 min) and Iranian (soaking in 20 % NaCl in water for 30 min, drying at 60 °C for 2 h and roasting at 135 °C for 20 min) hot‐air processes. The influence of roasting wild almonds on moisture and oil contents, crispness, fatty acid profile, volatile compounds, and odour intensity was investigated. Roasting causes changes in appearance, texture and flavour, due to dehydration, browning, lipid oxidation, and diverse structural changes. The moisture content and hardness of the samples significantly decreased with all roasting methods. Roasting resulted in higher amounts of characteristics aroma compounds and only microwave roasting increased the oil content. The final recommendation is that microwave roasting at 480 W for 4 min led to roasted almonds of high physicochemical [dark and intense colour (L*44.9, a*8.4, and b*19.6), the highest content of total volatile compounds (132 mg kg?1), 85.2 % of unsaturated fatty acids], and sensory (high intensity of “roasted almond” aroma) quality. Microwaves can be used for roasting wild almond as a quick, safe, and economical method.  相似文献   

20.
The oil content of sixAdansonia species (Bombacaceae family) of Madagascar (Adansonia grandidieri, A. za, A. digitata, A. fony, A. madagascariensis andA. suarenzensis) and Africa (A. digitata) ranges from 8 to 46%. All the oils give a positive response to the Halphen test. Malvalic, sterculic and dihydrosterculic acids were detected using gas liquid chromatography-mass spectrometry (GLC-MS). Epoxy or hydroxy fatty acids were not found in these oils. Fatty acid composition was determined by GLC using glass capillary columns coated with BDS and Carbowax 20 M. Results obtained for cyclopropenic fatty acids (CPEFA) were compared to those given by glass capillary GLC after derivatization with silver nitrate in methanol, by hydrogen bromide titration and by proton magnetic resonance (PMR). Good agreement was observed for the results given by the various methods. Malvalic acid content ranges from 3 to 28%, sterculic acid from 1 to 8% and dihydrosterculic acid from 1.5 to 5.1%. Odd-numbered fatty acids (Pentadecanoic and hepatadecanoic) were also observed in minute amounts (0.1–1.1%). Among the normal fatty acids, we observed mainly palmitic (21–46%), oleic (15–40%) and linoleic (12–32%). The relationship between fatty acid composition andAdansonia species is discussed.  相似文献   

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