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1.
The transgenic and non-transgenic soybean seeds oils were extracted and the composition and concentration of the fatty acids were analyzed by gas chromatography. Sixteen different fatty acids were detected in both transgenic and non-transgenic soybean oil: C14:0, C16:0, C18:1, C18:2, C18:3, C20:0, C20:1, C20:2, C22:0, C20:5, C22:1, C24:0 and C22:6. The concentration of 12 of 16 fatty acids (C14:0, C16:0, C18:1, C18:2, C20:0, C20:1, C20:2, C22:0, C20:5, C22:1, C24:0 and C22:6) in transgenic soybean oil were higher than those in non-transgenic one (P < 0.05). The concentration of C17:0 and C18:3 were lower than those in non-transgenic one (P < 0.05). The total fatty acids concentration increases by 12.6 % (P < 0.01). The degree of saturation of transgenic soybean oil increased from 58.7 to 69.8 % (P < 0.01). All the data above show that the insertion of foreign genes can change the concentration of fatty acids in plant oil. The mechanism for these changes should be studied.  相似文献   

2.
The aim of this study was to evaluate the inclusion of different oil sources and dietary supplementation with vitamin E on the composition of fatty acids in rooster meat. Two hundred and forty 30‐week‐old White Leghorn roosters were distributed in a completely randomized factorial arrangement of 5 × 2, using five oil sources (sunflower, soybean, canola, linseed and fish) and two levels of antioxidant (30 and 400 mg vitamin E kg?1 of diet). The intake of fish and canola oil in the diet reduced (P < 0.05) the content of saturated and unsaturated fatty acids in the thigh meat. Amongst the unsaturated fatty acids in the thigh, the fish and canola oil reduced (P < 0.05) the level of ω6 fatty acid, with a consequent decrease in the ratio ω6:ω3. The diet with fish oil increased (P < 0.05) the content of C22:6ω3 in the thigh meat. The use of linseed oil resulted in a significant reduction of the ratio of ω6:ω3 fatty acid in the thigh. The use of soybean oil in the diet increased (P < 0.05) the content of saturated and unsaturated fatty acids in the thigh, specifically in the content of ω6. The inclusion of vitamin E increased the polyunsaturated fatty acids in the chest meat, such as C18:3ω3, C20:5ω3 and C22:6ω3. Copyright © 2004 Society of Chemical Industry  相似文献   

3.
The purpose of this study was to investigate the quality deterioration of pressed soybean oil (PSBO), first grade solvent extracted soybean oil (FG‐SESBO) and third grade solvent extracted soybean oil (TG‐SESBO) with respect to time at 180 °C. It was found that there was a significant increase in total polar material (PM; P < 0.01) and free fatty acids (FFA; P < 0.05) in PSBO, FG‐SESBO and TG‐SESBO with increased time of frying. After forty‐five frying cycles, the final concentration of total PM was significantly higher in TG‐PSBO (30.39%) than in PSBO (21.10%) and FG‐SESBO (25.93%; < 0.05). During frying cycles, the final acid value (AV) was significantly higher in PSBO (0.84 ± 0.02 mg KOH/g fat) than in TG‐SESBO (0.59 ± 0.01 mg KOH/g fat) and FG‐SESBO (0.56 ± 0.03 (mgKOH/g oil; < 0.05). The content of saturated fatty acids in the three types of frying oils was significantly increased after forty‐five cycles of frying. However, even larger changes were observed in the content of unsaturated fatty acids, with decreases in C18:2, 9 c 12 c and C18:3, 9c 12c 15c and increase in C18:1, 9 c. The highest increasing slopes of PM and AV were observed in the TG‐SESBO.  相似文献   

4.
BACKGROUND: The effects of rosemary extract on the fatty acid profile of sea bream fillets cooked by different methods (oven baking, grilling and pan frying) as well as the effects of different reheating methods (microwave and conventional oven) on the fatty acid composition of fish after frozen storage for 4 months were investigated. RESULTS: The proportion of saturated fatty acids increased only slightly in fried samples but significantly in oven‐baked and grilled samples, while the proportion of polyunsaturated fatty acids (PUFAs) increased significantly in fried samples but only slightly in oven‐baked and grilled samples. The proportion of monounsaturated fatty acids remained relatively constant after cooking. Of the fatty acids analysed, the most significant increases (P < 0.05) were observed in C18:1n‐9 and C18:2n‐6 and the most significant decreases (P < 0.05) in C14:0, C16:1, C20:5n‐3 and C22:6n‐3. Although sea bream fillets fried in sunflower oil showed an increase in PUFAs, the lowest eicosapentaenoic and docosahexaenoic acid contents were found in fried samples. CONCLUSION: Sea bream fillets treated with rosemary extract showed slower oxidation than untreated fish. Neither conventional nor microwave reheating after frozen storage for 4 months had a detrimental effect on the fatty acid profile and its stability. Copyright © 2009 Society of Chemical Industry  相似文献   

5.
为快速准确对掺伪米糠油进行定量检测,将棕榈油、棉籽油、菜籽油、大豆油掺入纯米糠油,气相色谱法测定C10∶0、C14∶0、C16∶0、C16∶1、C18∶0、C18∶0、C18∶1、C18∶1、C18∶2、C18∶3、C20∶0、C20∶1、C22∶0、C22∶1的含量,利用向量夹角余弦法计算纯米糠油与掺伪米糠油的相似度,建立了掺伪量与相似度的线性模型.米糠油掺混棕榈油,计算模型为y =5.802 3x3-17.469x2-0.269 2x +99.99(R2 =0.999 6).米糠油掺混菜籽油,计算模型为y=-23.62x3-8.380 6x2-6.138 3x+ 100.12(R2=0.999 4).米糠油掺混棉籽油,计算模型为y=-240.52x5+ 677.8x4-697.92x3+ 312.09x2-66.998x+ 99.97(R2=0.999 3).米糠油掺混大豆油,计算模型为y=12.33x3-26.047x2-2.6855x+100.05(R2=0.999 1).  相似文献   

6.
Syrian Kaissy cv olive fruit (SKOF) was irradiated (0, 1, 2, and 3 kGy). Oils were extracted from irradiated and un-irradiated olive fruits. Fatty acid profiles of Syrian Kaissy cv olive oil (SKOO) were measured by gas chromatography immediately after irradiation and after 6, 12, 24, and 36 months of storage. Results of the study showed that composition of fatty acids of SKOO were determined as palmitic (C16:0) (14.69%), palmitoleic acid (C16:1) (1.18%), stearic (C18:0) (2.19), oleic (C18:1) (68.94%), linoleic (C18:2) (12.22%), and linolenic acid (C18:3) (0.79%). The fatty acid composition of SKOO contains a healthy mixture of all the types of saturated mono-unsaturated and poly-unsaturated fatty acids. The data showed an increase (p < 0.05) in the percentage of the total saturated fatty acids and decrease (p < 0.05) in the percentage of the total unsaturated fatty acids of SKOO during storage. In general, there were no significant (p > 0.05) differences in fatty acids compositions of both oils extracted from irradiated and un-irradiated SKOF.  相似文献   

7.
Eight 1st-lactation cows were given four dietary treatments in a duplicated 4×4 Latin square experiment. Diets consisted of hay and soya bean meal together with barley, formaldehyde-treated barley, oats or formaldehydetreated oats (approximately 34:12:54 on a dry matter basis). Barley diets supplied 211 g fatty acids d?1, oats diets supplied 537 g d?1. The fatty acid composition (g kg?1 total fatty acids) for barley diets was: 300 (16:0); 20 (18:0); 150 (18:1); 470 (18:2); 60 (18:3). Corresponding values for oats diets were 180, 20, 390, 380 and 30 g kg?1. Formaldehyde treatment of the cereals tended to increase milk yield and reduce milk fat content (P<0·01 for barley) but did not affect milk fatty acid composition. Feeding oats in replacement for barley significantly (P<0·05) increased milk yield and lactose yield and reduced milk fat content (P<0·05 for the untreated cereals) and protein contents (P<0·01) without significant effects on milk fat or protein yields. Oats diets led to significant (P<0·001) reductions in the content of 8:0–16:0 fatty acids in milk fat with associated increases (P<0·001) in the content of 18:0 and 18:1. Changes in milk fat content of 18:2 and 18:3 acids were small. The results show the inclusion of oats in the cow's diet to be a means of reducing the saturated fatty acid content of milk fat thereby improving the nutritional value of milk and milk products and their appeal to the health-conscious consumer.  相似文献   

8.
In this study, oil content and fatty acid composition of apple and pear seeds were analyzed. Apple (cv. red Fuji) seeds and pear (cv. Dangshan Suli) seeds contained a large quantity of oils (apple seed oil, 291 g/kg seed; pear seed oil, 179 g/kg seed). Eleven types of fatty acids were identified in apple and pear seed oil; c16:0, c16:1, c18:0, c18:1, c18:2, c18:3, c20:0, c20:1, c20:2, c22:0, and c24:0. The dominant fatty acids in apple seed oil were c18:1 (43.03 g/100g oil), c18:0 (26.47 g/100g oil), and c16:0 (5.60 g/100g oil). The same three fatty acids were also dominant in pear oil (c18:1, 56.80 g/100g oil; c18:0, 20.28 g/100g oil; and c16:0, 6.39 g/100g oil). Compared with previous research, an additional six fatty acids were found in apple seed oil (c16:1, c18:3, c20:1, c20:2, c22:0, and c24:0). Unsaturated fatty acids comprised 70.598 g/100g oil of apple seed oil and 77.846 g/100g oil of pear seed oil. In conclusion, apple seeds and pear seeds contain a large quantity of oil comprised of many fatty acids, especially unsaturated fatty acids. These data suggest that apple and pear seeds could be new sources of edible oils.  相似文献   

9.
Sixteen Holstein–Friesian dairy cull cows were offered either ad libitum grass (G) or red clover (RC) silage for 12 weeks. Dry matter (DM), total nitrogen, and pH was higher for the RC than the G silage and organic matter, water-soluble carbohydrate, fibre, DM digestibility, ammonia-N, vitamin E and acetic acid higher for the G silage (P < 0.05). Fatty acid compositions were different (P < 0.05) with G silage having higher levels of C12:0, C14:0, C16:1cis−9, C18:3n−3 and total fatty acids whereas RC had higher levels of C18:0, C18:2n−6 and C20:0. Daily liveweight gain was high and not different between groups (average 1.22 kg/d). Body condition score and back fat thickness at slaughter along with conformation, fat grade and slaughter weight were not different between groups. Animals offered the G silage produced larger M. longissimus length (P < 0.01) and a trend (P < 0.1) for width. RC fed animals had higher proportions of C18:3n−3 (P < 0.001), total n−3 fatty acids (P < 0.01) and total PUFA compared to animals offered the G silage despite greater intakes of these fatty acids on G (P < 0.001). Vitamin E concentration and stability of aged meat during simulated retail display, were lower (P < 0.05) from animals offered RC than animals offered G. Shear force and ultimate pH, however were not different in steaks and sensory attributes were similar; the only difference being a higher score (P < 0.01) for fishy in the RC steaks. The results suggest that feeding high DMD silage to dairy cull cows can result in a high standard of finish and liveweight gain. Furthermore RC silage as opposed to G silage can increase the beneficial fatty acid profile of the resultant meat.  相似文献   

10.
The aim of this work was to study the seasonal variation of the proximate and fatty acid compositions in the round herring (Etrumeus teres) and tub gurnard (Chelidonichthys lucernus) caught from the North‐Eastern Mediterranean Sea. Proximate compositions and fatty acid contents of both fish species showed statistically significant seasonal variations (P < 0.05). While the protein contents were at its highest in winter, the lipid contents were at its highest in autumn. The main fatty acids were C16:0 (palmitic acid), C18:0 (stearic acid), C16:1 n‐7 (palmiteoleic acid), 18:1 n‐9c (oleic acid), C20:5 n‐3 (eicosapentaenoic acid) and C22:6 n‐3 (docosahexaenoic acid). The total polyunsaturated fatty acid in round herring was highest in winter, whereas that in tub gurnard was highest in spring.  相似文献   

11.
《Food chemistry》2004,88(1):1-6
Different brands of sardines canned in soybean oil and tomato sauce, that are commercialized in Brazil, had their proximate composition, cholesterol content and fatty acids composition analyzed. Protein contents were equivalent to the values found for sardines in natura, ranging from 19.8 to 24.4%. High variations of the total lipids content (5.30–16.8%) were verified; the highest levels were found for sardines canned in soybean oil. The cholesterol content ranged from 50.4 to 65.1 mg/100 g. The highest levels of essential C18:2n  6 and C18:3n  3 fatty acids were found in sardines canned in soybean oil. The EPA (C20:5n  3) and DHA (C22:6n  3) concentrations ranged from 5.39 to 15.1% and from 3.89% to 9.51%, respectively, and the highest levels were observed in sardines canned in tomato sauce.  相似文献   

12.
The pomfret, Pampus punctatissimus, is an important fisheries resource in China, but little is known about its amino acid and fatty acid compositions. Pomfret muscle contained 18.6% crude protein and 4.95% crude fat. Pomfret protein has a well-balanced amino acid composition, with high amounts of glutamic acid (114 mg/g), lysine (82.8 mg/g), leucine (76.7 mg/g), and aspartic acid (76.0 mg/g). Twenty two fatty acids were found in pomfret oil and saturated fatty acids were the most abundant (48.3%). Palmitic acid (16:0) was the dominant fatty acid, followed by oleic acid (18:1), DHA (22:6n-3), myristic acid (14:0) and stearic acid (18:0), with percentages of 30.5, 26.3, 12.2, 7.37 and 6.86, respectively. The ratio of n-3/n-6 polyunsaturated fatty acids (PUFAs) was 8.04; thus, pomfret muscle is rich in n-3 PUFA.  相似文献   

13.
Heterocyclic amines (HAs) as potent mutagens are formed in meat floss which is a boiled, shredded and fried traditional meat product. In this study, effects of frying oils (lard, soybean oil and palm oil) on the formation of HAs in meat floss during frying have been investigated. The results showed that the contents of Norharman, Harman, AαC and MeAαC in meat floss that treated with lard and palm oil were higher than soybean oil which contained less saturated fatty acids (P < 0.05). The contents of total HAs in meat floss that treated with palm oil at 150 °C and 180 °C were significantly higher than that treated with soybean oil and lard (P < 0.05). In conclusion, meat floss treated with soybean oil at 120 °C, 150 °C and 180 °C contained lowest levels of HAs and soybean oil could be used as lard substitution to produce healthy meat floss.  相似文献   

14.
Forty eight Californian×New Zealand White rabbits were randomly distributed in three groups of 16 animals each. A control (with no added fat) and two diets enriched at a rate of 30 g fat kg-1 were used. Olive oil and sunflower oil were used as sources of fat for the fat-supplemented diets. Branched chain (BCFA) and n-odd-numbered carbon fatty acids (ONFA) in the perirenal fat depots of control animals were respectively 5 and 22 mg g-1 of total fatty acids, while in fat-enriched diets they were around 3 and 16 mg g-1, respectively. The ratio of unsaturated: saturated fatty acid in perirenal fat was 1·25:1 when the control diet was administered and around 1·80–1·95:1 in fat-enriched diet groups, which represents approximately a 50% increase (P<0·01). However the melting points of the fats showed little difference (NS) between the control group and the group with olive oil addition whilst the sunflower oil-supplemented group showed only a 5·7% lower value (P<0·01). In a second experiment in which diets with equal digestible energy and protein were used, reductions in total amounts of ONFA (P<0·01) and BCFA (P<0·05) were observed in the perirenal fat of animals receiving the fat-enriched diets. The addition of fat depressed the concentrations of ONFA and BCFA, which may act to maintain the consistency of fat in a narrow range, avoiding to some extent the production of undesirable soft and floppy carcasses. © 1997 SCI.  相似文献   

15.
Our objectives were to investigate the proximate composition of two desert truffles (Terfezia claveryi Chatin and Picoa juniperi Vittadini) and to determine the effects of freezing and canning on proximate composition. The moisture content of T claveryi and P juniperi was 730.9 g kg?1 and 637.8 g kg?1 respectively; ash was 42.5 g kg?1 and 82.1 g kg?1 respectively; protein was 159.5 g kg?1 and 225.4 g kg?1 respectively; lipids were 69.5 g kg?1 and 199.4 g kg?1 respectively; fibre was 83.2 g kg?1 and 130.4 g kg?1 respectively; and carbohydrates were 645.5 g kg?1 and 366.6 g kg?1 respectively. The fatty acids composition showed high quantities of linoleic acid 18:2 (45.4% in T claveryi and 53.0% in P juniperi), the rest of the fatty acids in decreasing order were 16:0 > 18 : 1 > 18 : 3 18 : 0 + 22 : 0 > 20 : 0 + 24 : 0 > 14 : 0 + 22 : 1 > 15 : 0 + 16 : 1 + 17 : 0 + 21 : 0 in T claveryi and 18 : 1 > 16 : 0 > 18 : 0 + 18 : 3 + 16 : 1 + 20 : 0 + 22 : 1 > 14 : 0 + 24 : 0 > 15 : 0 + 17 : 0 + 22 : 0 in the P juniperi. Little loss of ash, protein and lipids was observed as a result of industrial processing (p < 0.05). Copyright © 2003 Society of Chemical Industry  相似文献   

16.
The effect of including additional oil, incorporated as whole rapeseeds, in the diet of 64 Holstein–Friesian dairy cows (32 mid‐ and 32 late‐lactation) at pasture on animal performance and milk fat composition and properties was followed over a continuous trial of 20 weeks duration. Within two stages of lactation (mid, 130 ± 16.2 days, or late, 231 ± 58.9 days), cows were allocated to concentrate treatments representing four levels of rapeseed oil inclusion, 0 (control), 200, 400 and 600 g oil day?1. Oil inclusion had little effect on milk yield but decreased milk fat content significantly (P < 0.01), with a mean depression of 0.40% at the highest level of oil inclusion. The content of milk protein also decreased with increasing addition of oil, but the decrease was smaller than the milk fat depression and was not statistically significant. Increasing the level of rapeseed oil in the diet to 600 g oil day?1 resulted in linear changes in milk fat and protein concentrations which were described by regression equations. For each 100 g of rapeseed oil added to the diet, milk fat content decreased by 0.068% in mid‐lactation cows and 0.061% in late‐lactation cows, while protein content decreased by 0.026% in mid‐lactation cows and 0.028% in late‐lactation cows. Total unsaturated fatty acid content of milk fat also increased in a linear fashion with increased level of oil addition, from 345.7 g kg?1 total fatty acids in control milk fat to 459.3 g kg?1 total fatty acids at 600 g oil day?1, while total saturated fatty acids decreased in the same milk fats from 640.7 to 522.2 g kg?1 total fatty acids. These changes were reflected in lower solid fat contents (SFC) in the milk fat at the lower temperatures of measurement, eg 41% SFC at 5 °C at the highest level of oil inclusion compared with 52% in the control milk fat. However, SFC at 20 °C showed little difference with increasing level of dietary oil addition, an important factor in maintaining product integrity at room temperatures. The relatively high content of the monounsaturated fatty acid C18:1 (345.5 g kg?1 total fatty acids at 600 g oil day?1) and low content of polyunsaturated fatty acids (total C18:2 and C18:3 <40 g kg?1 total fatty acids at 600 g oil day?1) ensured that the oxidative stability of the treatment and control milk fats did not differ significantly. Stage of lactation had an unexplained effect of consistent magnitude on milk fat composition throughout the trial period, with late‐lactation animals producing milk fats containing a significantly (P < 0.001) higher proportion of unsaturated fatty acids than the mid‐lactation animals. Changes in the proportions of unsaturated fatty acids in milk fat, as reflected by changes in iodine value, were established within 2 weeks of the trial commencing and persisted over the 20 weeks of the trial duration. No adverse effect on animal health from this type of dietary manipulation was identified. Copyright © 2004 Society of Chemical Industry  相似文献   

17.
The objective of this study was to identify genetic variants in the bovine fatty acid synthase (FASN) gene and to evaluate associations with fatty acid composition from longissimus lumborum muscle using 90 purebred Hanwoo steers. Sequence alignments observed 6 genetic variants located in exons 20, 24, 32, 34, and 39, and PCR–RFLP analysis confirmed these variations. Genotypes of the g.15532A>C locus were significantly associated with Linolenic acid (C18:3), and genotypes of the g.17924G>A locus were significantly associated with Palmitic (C16:0), Palmitoleic (C16:1), Oleic (C18:1), saturated fatty acids, and unsaturated fatty acids. The analysis revealed that SFA and UFA showed significant correlations with fatty acid composition (Myristic (C14:0), Palmitic (C16:0), Stearic (C18:0), Oleic (C18:1), and Eicosenoic (C20:1) acids). Oleic acid (C18:1) was negatively correlated with Myristic (C14:0), Palmitic (C16:0), and Palmitoleic (C16:1) acids (P < 0.001).  相似文献   

18.
This study aims to compare chemical, physical and sensorial parameters of the Wels catfish (Silurus glanis), hot smoked using vine, poplar, lemon tree and oak sawdust as well as corncob. Significant differences (P < 0.05) in proximate composition were found between fresh and smoked samples; however, the changes in fatty acid composition were less significant. In the fatty acid composition of control group, monounsaturated fatty acids (41.60%) had the highest share in fatty acids, which was followed by saturated fatty acids (29.95%) and polyunsaturated fatty acids (28.34%). The major fatty acids were observed to be C16:0, C18:0; C16:1 n‐7, C18:1 n‐9c, C18:1 n‐9t and C18:2 n6c. There were significant differences (P < 0.05) between the groups considering their colour measurement results. General preference criteria such as appearance, odour, texture, colour and taste were chosen for the sensorial analysis, which were rated by the panellists. According to the results of overall appearance, the fillet pieces smoked with lemon tree (9.00), poplar (8.66), corncob (8.00), oak (7.33) and vine (5.33) sawdust were determined as the most preferred, in order.  相似文献   

19.
Mortadellas manufactured using Caiman yacare meat (70%) and pork fat (30%) were reformulated by substituting pork fat with increasing amounts of soybean oil (25%, 50%, and 100%) and evaluated 7, 30, and 60 days post-manufacture. The substitutions resulted in an increase in fat content and in the percentage of polyunsaturated fatty acids (total PUFA; 18:2 n − 6 and 18:3 n − 3), and a reduction in saturated fatty acids (total SFA; 14:0 and 16:0). These alterations reduced (P < 0.01) the indices of atherogenicity and thrombogenicity by 4- to 5-fold in the formulation with 100% soybean oil compared to the original formulation. The levels of TBARS obtained at day 7 were positively correlated (P < 0.01) with 18:2 n − 6 and 18:3 n − 3 (r = 0.83 and 0.84, respectively) and negatively correlated with 17:0 and 17:1 (r = − 0.91 and − 0.89, respectively). All formulations received favourable overall acceptability by the sensory panel.  相似文献   

20.
Eight fish species common to the Pacific Northwest coastal waters were categorised according to total lipids in a ranking from lean fish (e.g. walleye pollock) to oily fish (e.g. herring) species. Comprehensive fatty acid signatures were compared on both the relative proportion of total fatty acids and the proportion of total carcass lipid content. Generally, fish species from the Pacific coast had a relatively high proportion of n-3 highly polyunsaturated fatty acids (n-3 HUFAs), of which more than 80% was accounted for by C20:5n-3 (EPA) and C22:6n-3 (DHA), with species-specific and lower proportions of oleic acid (C18:1n-9) and palmitic acid (C16:0) also dominating. The MUFA contents of fish were lower (P < 0.05) in the lipids of lean and low-fat fish compared to those of fattier species. In contrast, higher (P < 0.05) proportions of polyunsaturated fatty acids (PUFAs) existed in the low-fat species with DHA contents ranging from 18% to 29% in the low-fat fish and from 8% to 10% in the fattier fish, such as herring and capelin. Expressing the same fatty acid content data in terms of absolute amount of fatty acids (e.g. gFA/100 g wet tissue) showed that both EPA and DHA contents in the flesh of pollock and hake were indeed many fold lower than those found in fatty fish, such as herring. The findings confirm that it is important that both the total lipid content and the fatty acid composition of these Pacific fish food sources be considered when making evaluations on the nutritional quality.  相似文献   

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