Peanut oil: Compositional data

The major fatty acids of peanut oil acylglycerols are palmitic (C16:0), oleic (C18:1), and linoleic (C18:2) acids, and only a trace amount of linolenic fatty acid (C18:3) is present. Thus they have a very convenient oxidative stability and have been considered premium cooking and frying oils. This paper provides information about compositional data of peanut oil taking into account major (triacylglycerols and their fatty acids) and minor (free fatty acids, diacylglycerols, phospholipids, sterols, tocopherols, tocotrienols, triterpenic and aliphatic alcohols, waxes, pigments, phenolic compounds, volatiles, and metals) compounds. Moreover, the influence of genotype, seed maturity, climatic conditions, and growth location on peanut oil chemical composition is considered in the present report. In addition, peanut oils from wild species found in South America as well as from peanut lines developed through conventional breeding are also compared.     

Variability in fatty acid composition amongArachis genotypes: A potential source of product improvement

Research on peanut (Arachis hypogeae L.) genotypes has shown a high degree of genetic variability in fatty acid composition. The two major oil fatty acids, oleic and linoleic, range between 36–69% and 14–40%, respectively, and together make up 75–85% of total fatty acids. The very long chain (C₂₀–C₂₄) fatty acids make up 4–9%, palmitic acid 7–13%, and stearic acid 2–5% of total fatty acids. Stability of oil samples as measured by length of autoxidation induction period at 60 C shows variable but statistically significant (P<0.01) correlations with levels of linoleic acid; peanut butter samples show similar patterns of stability. Selection for lower levels of linoleic acid in the development of new varieties of peanuts should results in products with significantly improved shelf life. Some genotypes show consistent differences in oil stability patterns that are not related to oil linoleic acid content. Analysis of entries from 16 wildArachis species collections revealed levels of oil linoleic acid higher than those found inA. hypogaea. One species,A. villosulicarpa, contained 49% linoleic acid and 21% very long chain acids. The range in linoleic acid withinA. hypogaea and availability of suitable techniques for measuring selection progress give scope for product improvement through breeding.     

Commercial Runner peanut cultivars in the USA: Fatty acid composition

Though peanuts are classified as a high‐fat food, they possess good proportions of fatty acids deemed as heart healthy. The fatty acid compositions of Runner peanuts were determined for commercially grown cultivars over two recent crop years. GC‐FID analyses revealed that the fatty acid levels for Runner peanuts were significantly (p <0.05) different among the normal, mid‐, and high‐oleic peanuts investigated. Oleic acid‐to‐linoleic acid (O/L) ratios were found to be 1.93 ± 0.30, 5.25 ± 1.12, and 16.9 ± 5.20 for normal, mid‐, and high‐oleic peanut lipids, respectively. Tamrun OL01 possessed a fatty acid profile characteristic of a mid‐oleic cultivar. From the sample set (n = 151), mean % weights for oleic acid and linoleic acid were 52.09 ± 2.84 and 27.38 ± 2.60 in normal, 69.33 ± 3.18 and 13.66 ± 2.35 in mid‐oleic, and 78.45 ± 2.05 and 5.11 ± 1.67 in high‐oleic peanuts, respectively. Cluster analysis segregated cultivars based on fatty acids into normal, mid‐, and high‐oleic groups. Factorial analysis revealed that cultivar effects were significant (p <0.01) for all fatty acids, except for lignoceric acid. Cultivar effects were also highly significant (p <0.001) for O/L, IV, unsaturated/saturated fatty acid (U/S) ratio, and % saturation. Significant crop year effects were shown for palmitic, oleic, arachidic, gondoic, and lignoceric acids, as well as U/S ratio and % saturation. Healthy unsaturated fats accounted for ?80% in all crop years and cultivars.     

Fatty acid composition of several varieties of soybeans

Summary Fatty acid composition of soybean oil of 18 currently important varieties from 43 locations in 16 states of the United States ranged from about 5% to 11% in linolenic, 43% to 56% in linoleic, 15% to 33% in oleic, and 11% to 26% in saturated acids. Oil of all 18 varieties had wide ranges in composition at different locations in two crop years. Within each group varieties tended to maintain the same relative order of fatty acid compositions of oil at all locations in the two years of this study. Publication No. 326 of the U. S. Regional Soybean Laboratory, Urbana, Ill.     

Performance of near-infrared reflectance spectroscopy (NIRS) in routine analysis of C18 unsaturated fatty acids in intact rapeseed

This study was aimed to evaluate the performance of near-infrared reflectance spectroscopy (NIRS) in the analysis of the oil composition for fatty acids like oleic (C18:1), linoleic (C18:2) and linolenic (C18:3) in zero-erucic acid rapeseed (Brassica napus L.). Intact-seed samples of 1094 lines from a breeding programme for high-oleic acid rapeseed were analyzed by both NIRS and gas chromatography (GC). Previously developed calibration equations were initially used for NIRS analyses. The accuracy of NIRS was considerably improved by including some samples of the actual breeding population into the original calibration set and developing new calibration equations. The inclusion of twenty randomly selected samples led to a reduction of the standard error of performance (SEP) from 2.6% to 1.9% for oleic, from 3.8% to 2.0% for linoleic, and from 1.1% to 0.9% for linolenic acid. The application of the new equations to the remaining population of 1074 samples resulted in coefficients of correlation between NIRS and GC values of 0.95 for oleic, 0.92 for linoleic, and 0.90 for linolenic acid. Furthermore, the effectiveness of a selection for high oleic, high linoleic, or low linolenic acid content based on NIRS data was demonstrated. The results of this study will help potential users to choose the optimal selection strategy in routine analysis of C18 unsaturated fatty acids by NIRS within a breeding programme.     

Proximate and Fatty Acid Composition of Some Commercially Important Fish Species from the Sinop Region of the Black Sea

The proximate and fatty acid compositions of the commercially important fish species (Engraulis encrasicolus, Alosa alosa, Belone belone, Scorpaena porcus, Pomatomus saltatrix, Mullus barbatus) from the Sinop region of the Black Sea were examined. The fat contents ranged from 1.26% (for scorpion fish) to 18.12% (for shad). The protein contents were min 14.54% (for red mullet) and maximum 20.26% (for belone). The fatty acid compositions of the fish ranged from 27.83 to 35.91% for saturated fatty acids, 19.50-33.80% for monounsaturated fatty acids and 15.25-40.02% for polyunsaturated fatty acids. Among the saturated fatty acids, palmitic acid (16:0) (17.75-22.20%) was the dominant fatty acid for all the fish species. As a second saturated fatty acid, myristic acid (14:0) was observed in four of the fish species and its content ranged from 4.72 to 7.31%. Whereas, for the other two fish species, the second saturated fatty acid was stearic acid (18:0) ranging between 4.54 and 10.64%. Among the monounsaturated fatty acids, those occurring in the highest proportions were oleic acid (18:1n-9c) (11.67-22.45%) and palmitoleic acid (16:1) (4.50-9.40%). Docosahexaenoic acid (22:6n-3) (5.41-28.52%), eicosapentaenoic acid (20:5n-3) (4.68-11.06) and linoleic acid (18:2n-6) (1.38-3.49%) were dominant polyunsaturated fatty acids, respectively. All the species, in particular the belone, the anchovy and the shad had high levels of the n-3 series.     

Studies on leguminous seeds

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%.     

Variation in Fatty Acid Composition in Indian Germplasm of Sesame

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.     

Fatty acid composition of oleaster pulp and pit oils

Fatty acid compositions of oleaster pulp and pit oils were determined by gas chromatography in 4 samples of different varieties. Pit oils were highly unsaturated, containing >90% linoleic, oleic, and linolenic acids, as well as traces of palmitoleic acid. Saturated fatty acids consisted of palmitic and stearic acids with traces of arachidic acid. Pulp oils showed fatty acid compositions entirely different from that of pit oils. They contained 9 saturated fatty acids, C₁₂ to C₂₄, some of them with high quantities, up to 34.9%, of the total fatty acids. Unsaturated fatty acids, mainly oleic and linoleic, with low quantities of palmitoleic and linolenic acids composed about one-third of the total fatty acids.     

Determination of fatty acids and some undesirable fatty acid isomers in selected Turkish margarines

The fatty acid composition and total trans fatty acid content in 10 margarines produced in Turkey were determined by capillary gas chromatography and Fourier transform‐infrared spectroscopy (FT‐IR) spectroscopy. The fatty acid composition ranged as follows: saturated fatty acids, C16:0 (palmitic) 11.3 to 31.8% and C18:0 (stearic) 5.7 to 8.7%, monounsaturated fatty acids, C18:1 (oleic) 21.8 to 35.7% and C18:1 trans isomers 0.4 to 27.4%, polyunsaturated fatty acid, C18:2 linoleic acid 5.2 to 40.2%. Some positional isomers of C18:1 as cis‐11‐octadecenoic acid varied from 0.7 to 4.6% and cis‐13 trace to 2.4%. The total trans fatty acid contents were between 0.9 and 32.0% when measured with capillary gas chromatography and between 0 and 30.2% with FT‐IR spectroscopy. Some of the margarines analyzed contained trace amount of trans fatty acids which could not be detected by FT‐IR spectroscopy.     

Structure of peanut oil triacylglycerols from cultivars of diverse genetic background

Triacylglycerols (TG) were isolated from peanut cultivars chosen to embrace known extremes in oleic and linoleic acid content, and the TG structure were determined using pancreatic lipase hydrolysis. Molar concentrations of oleic and linoleic acid insn-2-monoacylglycerols (MG) were highly correlated with molar concentrations in TG. Correlation coefficients were 0.99 in each case. Molar concentrations of oleic and linoleic in 2-MG are given by: MG_18∶1=1.37TG_18∶1-20.8; MG_18∶2=1.71TG_18∶2+0.66. Linoleicoleic ratios ranged from 0.2–1.1 for TG, 0.2–2.6 forsn-2-MG, and 0.2–0.6 for acids in the 1(3)-positions of TG. Molar concentrations of linoleic acid in the 1(3)-positions of TG ranged from 7–26%. The linoleic-oleic ratios and molar concentrations of 1(3) linoleic acid in some cultivars were similar to values that have been reported for relatively nonatherogenic corn oil and randomized peanut oil.     

Peanut triacylglycerols: Effect of season and production location

Stereospecific analysis of triacylglycerols from 4 peanut varieties grown for up to 3 years at 4 locations showed diversity in percentage fatty acid placement. Distribution of oleic and linoleic acids at each position was significantly correlated to the amount in the total triacylglycerol for varieties grown at one location. However, correlations for thesn-3 position were not significant when data from more than one location were analyzed together. Generally, higher percentages of oleic or linoleic acid in the triacylglycerol resulted in a greater proportion of the particular fatty acid in thesn-2 position. Apparently, fatty acid concentrations as influenced by growing location have a significant influence on peanut triacylglycerol structure.     

Variation in Fatty Acid Compositions, Oil Content and Oil Yield in a Germplasm Collection of Sesame (Sesamum indicum L.)

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.     

Multivariate Data Analysis of Fatty Acid Content in the Classification of Olive Oils Developed Through Controlled Crossbreeding

The fatty acid (FA) composition of 540 Tunisian virgin olive oil hybrids (VOO) were classified by principal component analysis (PCA). Pearson correlation between FA variables revealed an inverse association between C18:1 and C18:2; C18:1 and C16:0, while C16:0 and C16:1 were positively correlated. PCA yielded five significant PCs, which together account for 79.95% of the total variance; with PC1 contributing 36.84% of the total. Eigenvalue analysis revealed that PC1 was mainly attributed to C18:1, monounsaturated fatty acids (MUFA) and the ratios oleic/linoleic (O/L) and monounsaturated fatty acids/polyunsaturated fatty acids (MUFA/PUFA); PC2, by C16:0, saturated fatty acids (SFA) and the palmitic/linoleic ratio (P/L); PC3 by C18:2 and C22:0, PC4 by C18:0 and PC5, by C17:1. Then, PCA analysis indicated that in addition to C16:0, C18:0, C18:1, C17:1, and C22:0, MUFA, SFA and the ratios O/L, P/L and MUFA/PUFA were determined to be the main factors responsible for the olive oil hybrids discrimination.     

Fatty acid composition of oil from soybean leaves grown at extreme temperatures

Leaves from soybean (Glycine max (L.) Merr.) plants were assayed to determine if the relationship between temperature and relative fatty acid composition observed in the seed oil also existed for the triglycerides in the leaf oil. Leaf samples were harvested from eight soybean lines (A5, A6, C1640, Century, Maple Arrow, N78-2245, PI 123440 and PI 361088B) grown at 40/30,28/22 and 15/ 12°C day/night. At 40/30 and 28/22°C, seven fatty acids were observed at a level greater than 1.0%. These included the five major fatty acids found in the seed oil: palmitic (16:0), stearic (18:0), oleic (18:1), linoleic (18:2) and linolenic (18:3) acid; plus two fatty acids that had retention times the same as palmitoleic (16:1) and γ-linolenic (18:3 g) acid. In addition, an eighth fatty acid that had a retention time the same as behenic (22:0) acid was found in the leaves of all lines at 15/12°C. Palmitic, palmitoleic and stearic acid content did not differ significantly over temperatures. The oleic and linoleic acid content were each highest at 15/12°C, while the γ-linolenic and the linolenic acid content were each highest at 40/30°C. The fatty acid composition of the triglyceride portion of the leaf oil did not display the same pattern over temperatures as that observed for seed oil.     

The Influence of Growing Region on Fatty Acids and Sterol Composition of Iranian Olive Oils by Unsupervised Clustering Methods

Twenty seven Iranian olive oil samples were collected from different provinces to evaluate fatty acids and sterol compositions. The samples were collected from different geographical locations that varied in altitude, temperature, humidity and rain fall. The sample collected from the northern part of Iran by the Caspian Sea had higher oleic acid [G₂ sample (75.98%)] and lower linoleic acid [Go₅ sample (6.5%)] and palmitic acid [G₂ sample (10.78%)] concentrations than samples from the southern part of the country such as F₁ whose contents of C16:0, C18:1 and C18:2 were 15.27, 62.73 and 16.09%, respectively, in the southern part, the climate is dry and the temperature variation is wider and the elevation is 1,488 m. The results indicated that oleic acid was the predominant fatty acid with 62.7% for F₁ sample in the warmer climate at the south of Iran to 76.0% for G₂ sample in the cooler climate in the north of Iran. According to the results, the highest content of β-sitosterol was 87% related to samples G₉ and Z₃ from the north of Iran and the lowest content was 69.95% related to sample F_1–24 from the south of Iran. Clustering techniques such as principal component analysis and hierarchical cluster analysis were carried out on olive composition data to show similarities and discrimination between samples as a function of the cultivation zone. The two methods applied clearly showed the effect of growing regions on the distribution of the olive oil samples in the high dimensional space created by fatty acid and sterol compositions.     

Stability of pumpkin seed oil

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.     

Tissue culture of cocoa bean (Theobroma cacao L.): Incorporation of fatty acids into lipids of cultured cells

Suspension cell cultures of cocoa bean rapidly incorporated palmitic, stearic, oleic and linoleic acids into cellular lipids. Thus, 75 and 20% of [1-¹⁴C] palmitic acid was incorporated into polar lipids and triglycerides, respectively, after 48 hr. When [1-¹⁴C] oleic and [1-¹⁴C] linoleic acid were added separately, polar lipids consistently contained most of the radioactive fatty acids. Ca. 60% of the stearic acid accumulated as unesterified fatty acid in the cells. Palmitic and stearic acid were not desaturated, but oleic acid and linoleic acid were further desaturated. The kinetics of conversion of oleic acid and linoleic acid suggested a sequential desaturation pathway of 18∶1→18∶2→18∶3 in cocoa bean cell suspensions.     

Composition and metabolism of fatty acids in phospholipids of density-separated red cells of rats

Fatty acid compositions of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) and the rates of fatty acid esterification to these phospholipids (PL) were measured in intact rat red cell populations of different ages separated by density gradient centrifugation in order to clarify changes in membrane lipids of red blood cells during in vivo aging. Fatty acid compositions of PC and PE altered progressively as red cells became denser. Changes in unsaturated fatty acids occurred predominantly at the 2-position of PC and PE and those in saturated fatty acids at both positions. The esterification rates of 5 major fatty acids decreased as red cells became denser and those of oleic acid, linoleic acid and arachidonic acid to both PC and PE of fraction I cells (oldest cells) were 37–51% those of fraction IV cells (youngest cells). Reduction in the rates of fatty acid esterification appeared to occur in the course of red cell maturation because reticulocyte-enriched cell fractions showed 4.5–14.5 times higher rates of linoleic acid and arachidonic acid esterifications to PC and PE.     

越南安息香种子脂肪酸的在线甲基化-GC分析研究

建立了分析越南安息香种子油、果实和果壳的脂肪酸组成的在线甲基化-气相色谱法。将微克级的安息香样品与2μL衍生化试剂三甲基氢氧化硫（0.2 mol/L）加入裂解器,在350℃下瞬间反应,由气相色谱在线检测到8种脂肪酸甲酯成分,主要有棕榈酸（ C16∶0）、硬脂酸（ C18∶0）、油酸（ C18∶1）、亚油酸（ C18∶2）和亚麻酸（ C18∶3）,不饱和脂肪酸含量在84.5%以上,其中亚油酸含量最高,达47.29%。5次平行测定的相对标准偏差（ RSD）小于3.81%。并结合相似性分析法比较了4种不同产地的安息香种仁与6种食用油的脂肪酸组成,相似性结果表明不同产地的安息香种仁的脂肪酸组成相似,其脂肪酸组成与食用植物油相近,与玉米油的组成分布最为接近,相似系数在0.987~0.990,且越南安息香种子中人体必需的多不饱和脂肪酸含量（ C18∶2和C18∶3）与大豆油和葵花籽油相近,高于一般植物油,具有较高的营养价值。结果表明该法简便、快速、准确,适合越南安息香种子油脂的测定。