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1.
The objective of this work was to evaluate the quality of the oil extracted from sunflower achenes grown in Campo Novo de Parecis, the main producing region of Brazil, to optimize its use by the processing and food industries. In addition, the fatty acid profiles of the oil were checked for their adherence to the CODEX STAN 210–1999. Traditional and high-oleic genotypes were grown between 2014 and 2017 during trials with a randomized complete block experimental design with four replications. The contents of oleic, linoleic, palmitic, and stearic acids were determined using gas chromatography. The fatty acid profiles of traditional genotypes were observed to be outside the ranges established by the CODEX, with an oleic acid content above 39.4% and linoleic, palmitic, and stearic acid values lower than 48.3%, 2.7%, and 5.0%, respectively, as well as high-oleic sunflower oil with a stearic acid content of less than 2.6%. The availability of this information can, on the one hand, positively impact industries and encourage the use of better quality raw materials that are more technologically and nutritionally adequate. On the other hand, the commercialization of sunflower oil with a fatty acid profile outside the ranges established by CODEX can be difficult, because the contents are out of specification due to the climatic conditions in the cropping region.  相似文献   

2.
This study aimed to verify whether the fatty acid profiles of mid-oleic genotypes grown in the tropical region of Brazil fit the Codex Alimentarius and to examine the possibility of using traditional inbred lines to produce high-oleic hybrids. For this purpose, we assessed the fatty acid profile of six mid-oleic hybrids grown in environments with different minimum temperatures during oil formation in the achenes. The tests were conducted between 2015 and 2017 in an experimentally randomized complete block design with four replications. The oleic, linoleic, palmitic, and stearic acid contents were determined using gas chromatography. The mid-oleic hybrids presented varying levels of fatty acids, with oleic acid ranging between 43.6% and 84.6%, linoleic acid between 8.5% and 45.6%, palmitic acid between 3.9% and 5.7%, and stearic acid between 2.2% and 6.2%. Some of the fatty acid values were outside the ranges established by the CODEX STAN 210-1999 and were characteristic of high-oleic type sunflowers. This finding shows that we can take advantage of the potential of combining traditional inbred lines to produce high-oleic hybrids for faster and more economical breeding programs in these environments.  相似文献   

3.
The influence of temperature on the fatty acid composition of the oils from conventional and high oleic sunflower genotypes grown in tropical regions was evaluated under various environmental conditions in Brazil (from 0° S to 23° S). The amounts of the oleic, linoleic, palmitic and stearic fatty acids from the sunflower oil were determined using gas chromatography (GC). The environment exhibited little influence on the amounts of oleic and linoleic fatty acids in high oleic genotypes of sunflower. In conventional genotypes, there was broad variation in the average amounts of these two fatty acids, mainly as a function of the minimum temperature. Depending on the temperature, especially during the maturation of the seeds, the amount of oleic acid in the oil of conventional sunflower genotypes could exceed 70 %. Higher temperatures led to average increases of up to 35 % for this fatty acid. Although the minimum temperature had the strongest effect on the fatty acid composition, locations at the same latitude with different minimum temperatures displayed similar values for both oleic acid and linoleic acid. Furthermore, minimum temperature had little influence on the amounts of palmitic and stearic fatty acids in the oil.  相似文献   

4.
Plantings of sunflower,Heliantbus annuus L., were made 5 times between Feb. 2 and Nov. 15 in Florida so that the effect of planting date on the fatty acid composition of sunflower oil might be assessed. Eleven popular hybrids were planted at Gainesville, FL, on Feb. 2 and 28, April 2, and Aug. 14, and 15 hybrids were planted at Lake Worth, FL, on Nov. 15. Sunflower planted on Nov. 15 would be subjected to freezing temperatures if grown in Gainesville. Yields of sunflower achenes for the four planting dates at Gainesville declined with lateness of planting date. Oleic acid content of the oil (17.6–58.4%) was intermediate for the February plantings, highest for the April planting, and lowest for the late plantings. The linoleic acid content (32.5–71.0%) varied inversely with the oleic acid content. Because sunflower oil is needed for different purposes, such as for salad oil, for deep frying and for making margarines, oil low in linoleic acid (high in oleic acid) as well as oil high in linoleic acid (low in oleic acid) are needed. In Florida, adjusting the planting dates should result in the production of oil of the desired fatty acid composition.  相似文献   

5.
This paper presents the first investigation on the effect of enrichment refined olive oil by chlorophyll pigment extracted from Chemlali olive leaves during storage (6 months). The changes that occurred in the quality indices, fatty acids, sterol, and phenolic content were investigated during the storage of refined olive oil under RT (20°C) and accelerated conditions (50°C) in the dark. Additionally, the pigments (chlorophyll and carotene) changes during 6 months of oil storage were evaluated. At the end of the storage, more than 90% of chlorophyll pigments decomposed in all samples, while, carotene pigment loss was lower showing up to 60 and 85% loss for oil stored at 20 and 50°C, respectively, at the end of storage. The reduction of total phenolic compounds exhibited similar degradation profiles, being reduced by 5% and up to 60% for the enriched refined olive oil stored at 20 and 50°C in 6 months, respectively. In the fatty acid composition, an increase in oleic acid and a decrease in linoleic and linolenic acids were less significant in enriched than non‐enriched refined olive oil. On the other hand, sterol composition was less affected by storage in enriched oil samples. However, the sterol concentration of the oil samples showed an increase in β‐sitosterol, 24‐methylene cholesterol, stigmasterol, and a decrease in cholesterol, Δ5, 24‐stigmastadienol percentage at the end of storage. Based on the Rancimat method, the oils with added leaf pigment extract had the lowest peroxide value and the highest stability. After 6 months of storage, the oxidative resistance of refined olive oil fell to 0.2 and to zero for enriched refined olive oil stored at 20 and 50°C, respectively.  相似文献   

6.
Sunflower oil is the second most important virgin oil in Europe but, from the nutritional point of view, the assessment of this oil has become increasingly poorer over the last few years because of the high amount of linoleic acid in traditional sunflower seeds. Today sunflower oil with a high oleic acid content is coming more into the focus of interest since the fatty acid composition is more comparable to rapeseed and olive oil. Another important aspect is that the high content of oleic acid results in a high oxidative stability, making this oil interesting for a wide range of applications. A special challenge is the production of high‐quality tasty virgin sunflower oil because, in contrast to other raw materials, about 30% of sunflower seeds consist of hulls that are covered by waxes. During oil processing these waxes are co‐extracted with the oil, resulting in undesired turbidity of the oil on storage. Pressing of the raw material is done in a screw press or expeller and results in residue fat contents between 7 and 15% depending on the pressing conditions. We discuss two possibilities to avoid or to remove waxes by dehulling of the seeds or winterisation of the resulting oil. Dehulling is carried out by an impact dehuller with removal of the hulls by airflow and gravity. Removal of hulls before pressing improves the sensory quality of the oil because it results in products with a mild sunflower seed‐like nutty taste, while oils from whole seeds often have a woody and bitter taste. In addition, the development of heat during pressing is reduced if dehulled seeds are used for oil production. Conventional sunflower seeds are processed mainly in big oil mills, whereas in small and medium‐sized facilities organic raw material is in use.  相似文献   

7.
The objective of this study was to investigate the impact of water availability and temperature after flowering on oil, major fatty acid and sterol contents in seeds of standard and oleic sunflower genotypes, under managed and controlled field conditions. When water deficit was effective from the beginning to the end of anthesis, it modified the fatty acid composition of standard hybrids. When water was supplied, a major enhancement of oleic acid content was associated with a concomitant reduction of linoleic acid content and a decrease in saturated fatty acid contents. Higher temperatures increased the oleic acid content in seeds of standard hybrids. Oil content was enhanced under colder temperature and irrigation. The content of minor oil components, phytosterols, was also enhanced when seed development occurred under high temperature and severe water stress. As a whole, the data showed that combining water management, sowing date and choice of genotype may orientate the biosynthesis of seed components and thus generate seed composition variability suitable for industrial purposes.  相似文献   

8.
The fatty acid and triacylglycerol composition of a vegetable oil determine its physical, chemical and nutritional properties. The applications of a specific oil depend mainly on its fatty acid composition and the way in which fatty acids are arranged in the glycerol backbone. Minor components, e. g. tocopherols, also modify oil properties such as thermo‐oxidative resistance. Sunflower seed commodity oils predominantly contain linoleic and oleic fatty acids with lower content of palmitic and stearic acids. High‐oleic sunflower oil, which can be considered as a commodity oil, has oleic acid up to around 90%. Additionally, new sunflower varieties with different fatty acids and tocopherols compositions have been selected. Due to these modifications sunflower oils possess new properties and are better adapted for direct home consumption, for the food industry, and for non‐food applications such as biolubricants and biodiesel production.  相似文献   

9.
As the use of tocopherols as natural antioxidants increases, it is economically and agronomically important to determine the range, composition, and factors that affect their levels in oilseed crops, a major commercial source. In this study, tocopherols were quantified from seeds of wheat, sunflower, canola, and soybean. The breeding lines analyzed possessed a broad range of economically important phenotypic traits such as disease or herbicide resistance, improved yield and agronomic characteristics, and altered storage oil fatty acid composition. Complete separation of all four native tocopherols was achieved using normal-phase high-performance liquid chromatography with ultraviolet detection. Total tocopherol concentration among wheat germ oil samples ranged from 1947 to 4082 μg g−1. Total tocopherol concentration ranges varied from 534 to 1858 μg g−1 in sunflower, 504 to 687 μg g−1 in canola, and 1205 to 2195 μg g−1 among the soybean oils surveyed. Although the composition of tocopherols varied substantially among crops, composition was stable within each crop. Total tocopherol concentration and the percentage linolenic acid were correlated positively in soybean oils with modified and unmodified fatty acid compositions. Tocopherol concentration and degree of unsaturation were not correlated in sunflower or canola seeds with genetically altered fatty acid composition. These findings suggest that breeding for altered storage oil fatty acid composition did not negatively impact tocopherol concentrations in sunflower and canola as they apparently did in soybeans. When 12 soybean breeding lines were grown at each of five locations, significant correlations were observed among planting location, breeding line, tocopherol concentration, and fatty acid composition. Analysis of seeds that matured under three different controlled temperature regimes suggests that the relationship between tocopherol concentration level and unsaturated fatty acids in commodity (not genetically modified for fatty acid composition) oil types is due to temperature effects on the biosynthesis of both compounds.  相似文献   

10.
The fatty acid composition of corn oil can be altered to meet consumer demands for “healthful” fats (i.e., lower saturates and higher monounsaturates). To this end, a survey of 418 corn hybrids and 98 corn inbreds grown in Iowa was done to determine the fatty acid composition of readily-available, adapted, elite corn breeding materials. These materials are those used in commercial hybrid production. Eighty-seven hybrids grown in France (18 of which also were grown in lowa) were analyzed to determine environmental influence on fatty acid content. The parents of the hybrids and the inbreds were classified in one of four heterotic groups: Lancaster, Stiff Stalk, non-Lancaster/non-Stiff Stalk, and Other.t-Tests and correlation analyses were performed with statistical significance accepted at a level ofP≤0.05. The findings showed a wide range of fatty acid profiles present in adapted, elite corn breeding materials with ranges for each fatty acid as follows: palmitic acid, 6.7–16.5%; palmitoleic acid, 0.0–1.2%; stearic acid, 0.7–6.6%; oleic acid, 16.2–43.8%; linoleic acid, 39.5–69.5%; linolenic acid, 0.0–3.1%; and arachidic acid, 0.0–1.0%. Small amounts of myristic acid, margaric acid, and gadoleic acid also were found. Three lines had total saturates of 9.1% or less. Thirty-six of thet-tests involving hybrids showed significant differences among heterotic groups. There were small but significant correlations among protein, starch and oil content and the amounts of several fatty acids. Results from the corn grown in France vs. lowa demonstrated a large environmental effect that overwhelmed the genetic differences among lines. This study shows that for some attributes, a breeding program involving adapted corn breeding materials might produce the desired oil. Other types of oil (such as high-oleic) would have to be produced in a different manner, for example, by a breeding program with exotic breeding materials.  相似文献   

11.
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   

12.
Frying is a popular practice because of its unique sensory characteristics and low cost. The high temperature reached with this cooking method alters molecules present in the oil. The deterioration of the oil depends primarily on its chemical composition. The aim of this study was to evaluate the thermal stability of high oleic sunflower oil (HOSO), sunflower oil (SO) and mixed oil (MIX) during deep frying of French fries. Octanoic acid and unsaturated fatty acid (UFA)/saturated fatty acid (SFA) ratio showed a good correlation with total polar compounds (TPC) for all frying samples analyzed. HOSO and MIX were characterized by reduced levels of thermal degradation, while SO resulted in the highest values of oxidation products (highest TPC values). SO was also the oil more retained by the food matrix, whereas MIX was the least absorbed. HOSO and MIX, having a high oleic acid content (77.58 and 59.92 %, respectively) and a low linoleic acid content (13.42 and 25.70 %, respectively), showed the best characteristics for the frying process.  相似文献   

13.
This study determined the effect of adding mixed phytosterols, at various concentrations, on the thermal polymerization and oxidative stability index (OSI) of soybean and high‐oleic sunflower oils. The indigenous tocopherols and phytosterols were removed from the oils by molecular distillation. Pure phytosterols were added back to these stripped oils at concentrations of 0.25, 0.5, 1, and 2.5 wt‐%. These oils were heated at 180 °C, and triacylglycerol dimers and polymers, fatty acid composition, and residual phytosterols were determined. Added phytosterols at 1 and 2.5% significantly decreased thermal polymerization of stripped soybean oil over 8 h. Phytosterols at 2.5% significantly increased polymerization of stripped high‐oleic sunflower oil over 12 h. Added phytosterols did not affect the loss of polyunsaturated fatty acids in either oil. The decomposition of the added phytosterols was followed in both oils during the heating study. The loss of phytosterols in soybean oil ranged from 7 to 13%, while loss in stripped high‐oleic sunflower oil ranged from 13 to 20%. Phytosterols added at 1 and 2.5% significantly decreased the OSI for stripped high‐oleic sunflower oil. This research shows that added phytosterols, especially at higher concentrations, will have an impact on the thermal and oxidative stability of oils.  相似文献   

14.
A structured lipid (SL) with a substantial amount of palmitic acid at the sn‐2 position and enriched with capric acid (C), was produced in two enzymatic interesterification stages by using immobilized lipase, Lipozyme® TL IM (Novozymes North America Inc., Franklinton, NC, USA). The substrates for the reactions were high melting point palm stearin, high oleic sunflower oil and tricaprin. The SL was characterized for total and positional fatty acid profiles, triacylglycerol (TAG) molecular species, free fatty acid content, melting and crystallization profiles. The final SL contained 20.13 mol% of total palmitic acid, of which nearly 40 % was located at the sn‐2 position. The total capric acid content was 21.22 mol%, mostly at the sn‐1 and sn‐3 positions. The predominant TAGs in the SL were oleic–palmitic–oleic, POP and CLC. The melting completion and crystallization onset temperatures of the SL were 27.7 and 6.1 °C, respectively. The yield for the overall reaction was 90 wt%. This SL might be totally or partially used in commercial fat blends for infant formula.  相似文献   

15.
Oil value is determined by the functional qualities imparted from the fatty acid profile. Soybean oil historically had excellent use in foods and industry; the need to increase the stability of the oil without negative health consequences has led to a decline in soybean oil use. One solution to make the oil stable is to have high oleic acid (>70%) and lower linolenic acid content in the oil. Other fatty acid profile changes are intended to target market needs: low‐saturated fatty acid and high stearic acid content in the oil. The objective of this study is to determine the interaction of the high oleic acid oil trait with other alleles controlling fatty acid profiles. Soybean lines containing high oleic acid allele combinations plus other fatty acid modifying alleles were produced, and the seed was produced in multiple field environments over 2 years. Stable high oleic acid with low linolenic acid (<3.0%) was achieved with a 4‐allele combination. The target of >20% stearic acid in the seed oil was not achieved. Reducing total saturated fatty acids below 7% in a high oleic acid background was possible with mutant alleles of both an acyl‐ACP thioesterase B and a β‐ketoacyl‐[acyl‐carrier‐protein] synthase III gene. The results identified allele combinations that met the target fatty acid profile thresholds and were most stable across environments.  相似文献   

16.
The Chinese tallow tree (TT) has been widely considered to be an invasive species in the US without potential benefits. However, the literature on TT seeds is scarce and the effect of storage conditions on seed oil quality in particular has not been published to our knowledge. Prior research revealed that TT has a very high yield of seeds containing large percentages of long and short chain fatty acids (mainly palmitic fatty acid, along with some oleic, linoleic and linolenic fatty acids), which can be base transesterified into biodiesel. This study aims to address the issue of the quality of the kernel oil of TT seeds stored at different temperatures (4 °C and room temperature) and under controlled atmosphere storage conditions (3% CO2, 6% CO2, vacuum, normal headspace). The total storage time was 3 months with the oil quality being analyzed weekly. Extracted oil was analyzed by titratable acidity, peroxide value, oxidative stability index and fatty acid composition. These experiments provided evidence that, after 12 weeks of storage, a controlled atmosphere did not produce any remarkable advantage over low cost air storage. The results validate the belief that no elaborate storage conditions are required to store this economically promising high oil content biofuel feedstock.  相似文献   

17.
In the present study, changes in phospholipid compositions of liver microsomes, erythrocyte membranes, platelets, aorta, cardiac muscle and brain of rats fed olive oil were compared with those of rats fed sunflower oil. Four groups of rats starting at weaning were fed for four weeks a basal diet containing 5 or 25% olive oil or sunflower oil. We found that oleic acid was higher and linoleic acid was lower in membrane phospholipids of olive oil fed rats compared to sunflower oil fed rats. Polyunsaturated fatty acids of the n−3 series were markedly elevated in all tissues of rats on the olive oil diets relative to those on the sunflower oil diets. The results are consistent with a lower linoleic/linolenic acid ratio induced by the olive oil diets, suggesting a positive correlation between olive oil ingestion and n−3 polyunsaturated fatty acid levels in cell and tissue lipids. The study suggests that an adequate intake of olive oil may enhance the conversion of n−3 fatty acids.  相似文献   

18.
Plasma and liver lipids were studied in male weanling rats fed diets containing moderate levels of fat (6% by weight) as sunflower oil (SF diet, rich in linoleic acid), salmon oil (SM diet, rich in long-chain n-3 fatty acids), or a blend of peanut and rapeseed oil (PR diet, rich in oleic acid). After nine weeks of feeding, the fasting plasma cholesterol concentrations were 49 and 24% lower in groups SM and SF, respectively, as compared to group PR. Both dietary salmon oil and sunflower oil lowered the tricylglycerol concentration of plasma and liver but, unexpectedly, the response was higher with sunflower oil. Indeed, in group SM the values were 15 and 30% lower in plasma and liver, whereas in group SF, they were 24 and 53% lower, respectively. As compared to group PR, liver triacylglycerols and microsomes contained 2.5- and 2.3-fold less oleic acid, respectively, in group SF, and they were 9.2- and 3.2-fold enriched in n-3 fatty acids, respectively, in group SM. The liver triacylglycerol concentrations were correlated with changes in the microsomal Mg2+-dependent phosphatidate phosphohydrolase activity (r=0.47,P<0.01). As oleic acid, unlike long-chain n-3 fatty acids, is considered to promote the triacylglycerol synthesis and secretion, our findings suggest that changes in the membrane fatty acid composition could affect the triacylglycerol content of liver and plasma. Moreover, the availability within the liver, of oleic acid, predominantly incorporated into triacylglycerols, might limit the triacylglycerol production in SF-fed rats.  相似文献   

19.
20.
Fatty acid profile analysis is a tool for dietary investigation that may complement traditional stomach contents analysis. While recent studies have shown that the liver of sharks fed different diets have differing fatty acid profiles, the degree to which diet is reflected in shark blood serum and muscle tissue is still poorly understood. An 18-week controlled feeding experiment was undertaken using captive Port Jackson sharks (Heterodontus portusjacksoni). Sharks were fed exclusive diets of artificial pellets treated with fish or poultry oil and sampled every 6 weeks. The fatty acid profiles from liver, blood serum, and muscle were affected differently, with the period from which significant differences were observed varying by tissue and diet type. The total fatty acid profiles of fish oil and poultry oil fed sharks were significantly different from week 12 onwards in the liver and blood serum, but significant differences were only observed by week 18 in the muscle tissue of sharks fed different diets. The drivers of dissimilarity which aligned with dietary input were 14:0, 18:2n-6, 20:5n-3, 18:1n-9 and 22:6n-3 in the liver and blood serum. Dietary fatty acids accumulated more consistently in the liver than in the blood plasma or muscle, likely due to its role as the central organ for fat processing and storage. Blood serum and muscle fatty acid profiles were influenced by diet, but fluctuated over-time. The low level of correlation between diet and muscle FA profiles is likely a result of low levels of fat (<1 %) in the muscle and the domination of structural, cell-membrane phospholipids in shark muscle tissues. Our findings describe inter-tissue differences in the incorporation of fatty acids from the diet to consumer, which should be taken into account when interpreting dietary patterns from fatty acid profiles.  相似文献   

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