Comparison of fruit characteristics,oil properties and fatty acid composition of local Syrian Kaissy cv olive (<Emphasis Type="Italic">Olea europaea</Emphasis>)

Characterization of Syrian (Kaissy cultivar) olive fruits and evaluation of physic-chemical properties of oils were carried out during 3 years of production. The mean values of data for both measured and calculated variables of fruits were: grain length (21.89 mm), grain width (17.92 mm), length/width (1.22), weight of grain (3.79 g), weight of pulp (flesh) (3.19 g), weight of pit (0.60 g), pulp/pit ratio (5.35), crude oil (17.13%), water content (moisture) (51.34%). The 3 year average values of chemical properties of Syrian Kaissy cultivar olive oils (SKOO) including acid value, peroxide vale, Thiobarbituric acid value, iodine value(IV), saponification value, and phenolic content were 0.58%, 4.33 mEq O₂ kg^??1, 0.028 mg MDA kg^??1 oil, 90.77 g I₂, 100 g^??1, 194.91 mg KOH g^??1, and 218.08 g gallic acid kg^??1, respectively. Pefractive index (RI), and viscosity were 1.4666 nD at 25?°C and 139.56 mPa.s, respectively. However, the 2 years average values of Hunter’s color parameters of SKOO were; the lightness (L*= 66.91), redness (a* = 18.80), yellowness (b* = 29.08) and the color differences (?E?=?65.49). FA analysis of the SKOO used showed a high content of monounsaturated fatty acids (oleic acid 70.82% and palmitic acid 1.01%) and low polyunsaturated fatty acids (Linoleic acid 10.72% and Linolenic 0.82%) and saturated fatty acids (Palmitic 14.10% and stearic 2.57%). Results for 3 years production of Syrian Kaissy cultivar olive fruit and oil are discussed in detail.     

Stability of encapsulated olive oil in the presence of caffeic acid

The aim of this study was to investigate the influence of microencapsulation and addition of the phenolic antioxidant caffeic acid (CA) on the storage stability of olive oil. Olive oil in the absence or presence of 300 ppm CA was encapsulated in 1.5% w/w sodium alginate shells. Encapsulated oil (with/without added CA) and unencapsulated oil were stored at 20 or 37 °C for 30 days and then subjected to stability and quality evaluation based on peroxide value (PV), p-anisidine value (p-AV), Totox value, free fatty acid (FFA), total extractable phenolic content (TEPC), and fatty acid composition. The CA addition increased the stability and TPC of the final oil product. Oxidation changes were generally slower in the encapsulated oil samples. Both encapsulation and addition of CA preserved unsaturated fatty acids (UFAs) including C18:1 (omega-9 FA), C18:2 (omega-6 FA) and C18:3 (omega-3 FA). We conclude that the current oil encapsulation method using alginate microspheres could be a feasible approach to increasing olive oil stability. The addition of CA to olive oil not only provides additional protection to the oil, but also improves the nutritional values of the final oil product in terms of elevated TEPC and desired UFAs.     

PRODUCTION OF LOW-FAT FRANKFURTERS WITH VEGETABLE OILS FOLLOWING THE DIETARY GUIDELINES FOR FATTY ACIDS

Low-fat frankfurters (10% fat) were produced with vegetable oils following the dietary guidelines for fatty acids as suggested in the currently recommended diet (CRD) by the American Heart Association, the Grundy diet (GD) and the Mediterranean diet (MD). MD-frankfurters, produced with olive oil (31.82%) and soybean oil (17.51%), had the highest (P<0.05) ratio of monousaturated fatty acids (MUFA)/saturated fatty acids (SFA) minus stearic. CRD-frankfurters, produced mainly with cottonseed oil (40.70%) and soybean oil (6.90%), had the highest (P<0.05) content of polyunsaturated fatty acids (PUFA). GD-frankfurters, produced with cottonseed oil (34.04%) and olive oil (15.19%), had the highest (P<0.05) ratio of (C18:2 n-6)/(C18:3 n-3). Compared to high-fat frankfurters (27% all animal fat), low-fat frankfurters had lower (P<0.05) stearic acid and trans ω-9 oleic acid, higher (P<0.05) content of total PUFA, higher (P<0.05) ratio of (C18:2+C 18:3)/SFA minus stearic acid, and lower cholesterol content (52.60%-59.11%), were darker, redder and more yellow, firmer and less juicy, but had similar overall acceptabily.     

Omega-3 Fatty Acids in Lake Superior Fish

Proximate analysis and fatty acid composition of eight commercially important species of Lake Superior fish were determined. Palmitic acid (C16:0) was the predominant saturated fatty acid, accounting for 68–79% of total saturated acids. Oleic acid (C18:1) was the most abundant monounsaturated fatty acid. Linoleic acid (C18:2), linolenic acid (C18:3), eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) were the predominant polyunsaturated fatty acids. Brining, smoking and refrigerated storage caused a reduction in total lipid, but only a small loss in n-3 fatty acids. The data revealed that most Lake Superior fish examined were excellent sources of polyunsaturated fatty acids with very high levels of omega-3 (n-3) fatty acids, especially eicosapentaenoic and docosahexaenoic acids.     

Screening of microbes for lipases specific for saturated medium and long-chain fatty acids of milk fat

Over 250 microbial strains were screened for lipase activity specific towards saturated medium and long-chain fatty acids. Strains showing trimyristin (C14:0) hydrolysis on agar medium were further streaked on tricaprylin (C8:0) and on olive oil (mostly C18:1) agar to identify strains hydrolysing C12–C15 fatty acids with modest or no activity towards short-chain and unsaturated fatty acids. The twenty strains showing the desired specificity were grown as liquid cultures and analysed for p-nitrophenyl (p-NP) myristate hydrolysis in the presence of Triton X-100. Cells from the cultures showing the highest activity towards p-NP myristate were analysed for specificity towards p-NP esters of different fatty acid chain lengths. On the basis of the p-NP ester profiling, four lipase samples were selected for hydrolysis experiments on butter oil. Of these, the sample obtained from the cultivation of Didpodascus capitatus met the screening criteria: C12:0–C16:0 specificity and no preference towards C18:0 and C18:1 fatty acids.     

Fatty acid composition and sensory properties of Wels catfish (Silurus glanis) hot smoked with different sawdust materials

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.     

Fatty acid composition of advanced olive selections obtained by crossbreeding

BACKGROUND: An olive‐breeding programme aimed at obtaining new cultivars for olive oil production was initiated in Spain in 1991, with oil quality being considered one of the most important objectives. In this study the oil fatty acid composition of 15 advanced olive selections coming from crosses between ‘Arbequina’, ‘Frantoio’ and ‘Picual’ cultivars was evaluated. RESULTS: A strong genetic effect and significant differences between genotypes were obtained for all fatty acids and ratios evaluated. The results allowed the classification of genotypes into four groups according to their fatty acid composition, with the percentages of C18:1, C18:2 and saturated fatty acids being the main contributors to the total variation. The relationship between the results of the initial seedling population and those of the advanced selections indicated that an efficient selection for fatty acid composition could be carried out by considering only a single year of evaluation at the seedling stage. CONCLUSION: A quite different fatty acid composition in the oil of 15 advanced selections and their three genitors was obtained. These results suggest that new olive cultivars with fatty acid composition fulfilling consumer and market demands could be obtained through crossbreeding in the future. Copyright © 2008 Society of Chemical Industry     

宣威火腿与金华火腿中游离脂肪酸组成比较分析

以两年宣威火腿和金华火腿为对象,采用气相色谱-质谱联用法(GC-MS)分别对宣威火腿和金华火腿的皮下和肌内脂肪中游离脂肪酸的组成进行分析。结果表明:宣威火腿和金华火腿的肌内脂肪和皮下脂肪中均检测出22种游离脂肪酸,含量较高的脂肪酸为棕榈酸(C16:0)、硬脂酸(C18:0)、油酸(C18:1n9c)与亚油酸(C18:2n6c),且不同火腿及不同部位间的脂肪酸组成含量存在明显差异;金华火腿肌内及皮下脂肪中总游离脂肪酸含量分别为29.24、102.68 μg/mg,分别比宣威火腿高34.58%(p<0.05)、29.09%(p>0.05);宣威火腿和金华火腿肌内脂肪中饱和脂肪酸含量高于不饱和脂肪酸含量,皮下脂肪中不饱和脂肪酸含量高于饱和脂肪酸含量。金华火腿肌内、皮下游离脂肪酸含量均高于宣威火腿相应部位游离脂肪酸含量。     

Oxidative changes in hazelnut,olive, soybean,and sunflower oils during microwave heating

The effects of microwave heating for 3, 6, and 9 min at a frequency of 2450 MHz on fatty acid composition, tocopherols, iodine value, free fatty acids (%), peroxide value, conjugated dienes and trienes, and hexanal contents of refined hazelnut, soybean, sunflower, and virgin olive oils were investigated. A significant (p < 0.05) decrease was observed in linoleic and linolenic acids contents of soybean oil during exposure to microwave heating. Tocopherol contents of oil samples significantly decreased (p < 0.05) during microwave heating. Free fatty acids of the samples slightly increased and iodine value showed reduction throughout the process. Conjugated dienes contents of samples showed an increasing trend up to the 6 min, followed by a reduction at 9 min. Conjugated triene fatty acids of all the samples significantly increased (p < 0.05) throughout the application. While peroxide value showed increasing trend up to the 3 min and sharply decreased at 9 min, hexanal contents of refined hazelnut, virgin olive, soybean, and sunflower oils increased 63, 28, 55, and 389 fold, respectively, after 9 min exposure to microwave heating. Kinetic analysis of data showed that the reaction orders for peroxide and hexanal formation were zero and first order, respectively, and in the tested oils the reaction rate followed the order: soybean oil ? sunflower oil ? hazelnut oil ? virgin olive oil for peroxide, and sunflower oil ? soybean oil ? hazelnut oil ? virgin olive oil for hexanal formation. It was concluded that hexanal could be considered as a parameter for evaluation of the quality of oils exposed to microwave heating.     

Effect of cooking on the chemical composition of low-salt, low-fat Wakame/olive oil added beef patties with special reference to fatty acid content

Changes in chemical composition, with special reference to fatty acids, as affected by cooking, were studied in low-salt (0.5%)/low-fat patties (10%) with added Wakame (3%) and partial or total replacement of pork backfat with olive oil-in-water emulsion. The addition of Wakame and olive oil-in-water emulsion improved (P < 0.05) the binding properties and the cooking retention values of moisture, fat, fatty acids and ash, which were close to 100%. Partial and total replacement of animal fat with olive oil-in-water emulsion reduced (P < 0.05) saturated fatty acids (SFAs), while total replacement also reduced (P < 0.05) polyunsaturated fatty acid (PUFAs) contents. The fatty acid concentration in cooked patties was affected by product formulation. Unlike the case of all animal fat patties, when olive oil was added the cooking process increased (P < 0.05) SFAs, monounsaturated fatty acids (MUFAs) and PUFA n-3 (linolenic acid) and n-6 (linoleic acid) contents. Cooked formulated patties with seaweed and partial or total replacement of pork backfat by oil-in-water emulsion and with seaweed added were less calorie-dense and had lower SFAs levels, while samples with olive oil had higher MUFAs levels.     

Amino Acid and Fatty Acid of Abalone Haliotis Squamata Cultured in Different Aquaculture Systems

The aim was to analyze the amino acid and fatty acid of abalone Haliotis squamata cultured in different aquaculture systems. The percentage of total amino acid of abalone cultured in laboratory, floating cage, and longline system valued 11.02%, 9.53% and 8.24%. respectively. Abalone contained 14 saturated fatty acids and 16 unsaturated fatty acids. The saturated fatty acids of abalone were dominated by palmitenoic acid (C16:0) and steraenoic acid (C18:0). The high percentage of unsaturated fatty acids in abalone were oleat acid (C18:1n9), linolenic acid (C18:3n3), arachidonoic acid (C20:4n6) and eicosapentaenoic acid/EPA (C20:5n3).     

热水处理对近冰温贮藏鲜枣品质提高与膜脂代谢的相关性分析

以采后临泽小枣（Zizyphus jujuba Mill. cv. Linzexiaozao）为实验材料,探讨热水处理对近冰温贮藏鲜枣果实耐冷性与膜脂脂肪酸组分变化的影响。采后果实用60 ℃热水浸泡1 min,自然干燥后,装入带有若干小孔(孔径为2 mm)的聚乙烯塑料饭盒,置于(?1.5~?2)℃的冷库中贮藏,定期测定果实冷害指数、细胞膜透性、丙二醛(MDA)、脂氧合酶(LOX)活性及膜脂脂肪酸组分变化。与对照相比,贮藏50 d时,热水处理果实的冷害指数、相对电导率、MDA和LOX活性分别降低了7.56、17.93%、17.93 μmol/g·FW和15.84 U/g·FW,不饱和脂肪酸油酸(C_18:1)、亚油酸(C_18:2)和亚麻酸(C_18:3)的相对含量及膜脂脂肪酸不饱和指数(IUFA)、脂肪酸不饱和度(UFA/FA)分别增加了11.10%、9.13%、8.60%和55.17、0.65,饱和脂肪酸肉豆蔻酸(C_14:0)、棕榈酸(C_16:0)、硬脂酸(C_18:0)和花生酸(C_20:0)的相对含量也分别降低了54.10%、18.66%、17.93%和3.37%,且差异显著(P<0.05)。尤其是对照LOX活性与亚麻酸(C_18:3)的相对百分含量变化有极显著(P<0.01)的负相关性(r=?0.931)。结果表明,鲜枣在近冰温冷藏下发生冷害的程度与膜脂中亚麻酸（C_18:3）的相对含量变化存在相关性。热水处理抑制了鲜枣膜脂脂肪酸不饱和指数(IUFA)和脂肪酸不饱和度(UFA/FA)的下降,诱导膜脂中不饱和脂肪酸的降解速率减缓,从而维持较高的膜脂稳定性,使采后鲜枣近冰温贮藏的耐冷性增强。     

Curing properties of sodium nitrite in restructured goat meat (chevon) jerky

Known curing impacts on goat meat (chevon) is limited due to the low production and consumption of chevon products in the United States. This study, therefore, assessed sodium nitrite influences on the quality parameters of restructured chevon jerky and its stability. Inclusion of NaNO₂ increased (p < 0.01) the redness of chevon jerky (14.2 versus 8.17); however, the redness was decreased (p < 0.01) over a 30 d storage period. The texture properties and microbial counts of jerky were not influenced by NaNO₂. However, the total microbial counts increased (1.84 to 6.00 ± 0.468 log CFU/g; p < 0.01) with storage time in chevon jerky whether or not nitrite was included. Inclusion of NaNO₂ decreased (p < 0.05) thiobarbituric acid reactive substances values (4.26 versus 4.81 mg MDA/kg), which did not change during storage. Among 28 isolated fatty acids from chevon jerky, palmitic (C16:0), stearic (C18:0), oleic (C18:1n9), and linoleic (C18:2n6) acids were the major four fatty acids. Of the 21 positively identified volatile compounds, six terpenes (α-pinene, β-pinene, β-phellandrene, carene, limonene, and cubebene), octanone and nonanal were the most abundant compounds. Neither processing treatment nor storage time significantly influenced the concentration of individual fatty acids and volatile compounds. Cured jerky had higher (p < 0.05) sensory color and flavor scores compared to uncured jerky. Results indicated that inclusion of NaNO₂ might improve color and sensory properties, as well as control the lipid oxidation of chevon jerky. However, the reduction of lipid oxidation in jerky was not revealed in product fatty acid or volatile flavor compounds.     

Effects of cooking and reheating methods on the fatty acid profile of sea bream treated with rosemary extract

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     

紫外线辐照花生油贮藏过程中的脂肪酸组成分析

目的:紫外线辐照花生油在贮藏过程中变化情况。方法:将对照组花生油置于254 nm的紫外灯下辐照处理40 min,将紫外组和对照组花生油分别置于40、50和60 ℃的条件下加速氧化贮藏,对28 d贮藏过程中花生油的脂肪酸组成变化进行分析,通过主成分分析和相关性分析探究紫外线辐照花生油的脂肪酸组成在贮藏过程中的相互之间的关系。结果:经紫外线辐照花生油在加速氧化贮藏过程中饱和脂肪酸和单不饱和脂肪酸含量在贮藏21 d后呈迅速递增趋势,多不饱和脂肪酸在贮藏21 d后期呈迅速递减趋势,各种脂肪酸在贮藏过程中变化幅度比对照组大;温度越高,经紫外线辐照花生油各种脂肪酸组成在贮藏过程中变化幅度越大,当贮藏温度相对较低的时候,各种脂肪酸在贮藏过程中的变化不大;主成分分析和相关性分析表明,紫外线辐照花生油中亚油酸(C18:2n6)、亚麻酸(C18:3n3)与棕榈酸(C16:0)、硬脂酸(C18:0)、油酸(C18:1n9c)、花生酸(C20:0)、花生一烯酸(C20:1)、山嵛酸(C22:0)主要影响紫外组的脂肪酸组成,多不饱和脂肪酸与单不饱和脂肪酸、饱和脂肪酸存在极显著的负相关,单不饱和脂肪酸与饱和脂肪酸存在极显著的正相关。结论:紫外辐照花生油在贮藏过程中的脂肪酸组成比对照组的变化幅度大,较高的贮藏温度使紫外辐照花生油的脂肪酸组成和种类发生变化。     

The effect of gamma irradiation on oleic acid in methyl oleate and food

The objective of this study was to investigate the effects of gamma irradiation on changes in oleic acid of methyl oleate as well as of beef and olive oil. The samples were irradiated at doses ranging from 0 to 60 kGy and the fatty acid composition was then analyzed by GC–FID and GC–MS. Gamma irradiation upon methyl oleate induced the formation of trans octadecenoic acid and stearic acid in a dose dependent fashion, while it decreased the amount of oleic acid. These findings indicate that the 9-cis structure is responsible for the formation of trans and saturated configurations. Additionally, the formation of stearic acid was facilitated by high temperature during the irradiation. Conversely, irradiation dose and temperature during irradiation had no significant effect (p > 0.05) on the amount of trans or saturated fatty acids in the beef and olive oil.     

An influence of cooking on fatty acid composition in three varieties of common beans and in lentil

The fatty acid composition of three raw and cooked freeze-dried common bean varieties (Phaseolus vulgaris), namely enjevec, Semenarna 22 and Cipro, and of the lentil (Lens esculenta), var. Anicia, was determined and the influence of storage on their composition was studied. Analyses of fatty acid composition were conducted by in situ transesterification and capillary column gas-liquid chromatography. In raw milled beans average values of about 16% saturated fatty acids (SAT), 6% monosaturated fatty acids (MUFA) and 78% polyunsaturated fatty acids (PUFA) were found. Somewhat different values of 15% of SAT, 25% MUFA and 60% PUFA were found in lentil. In cooked beans the content of all fatty acids was slightly decreased. In cooked lentil the decrease was almost 50%, but the ratios of SAT, MUFA and PUFA in both cases were practically the same. After two years of storage at 4 °C the fatty acid content in raw milled beans was unchanged, but altered in cooked ones. The amounts of linoleic (18:2, n-6) and -linolenic (18:3, n-3) acid decreased, but myristic (14:0), margaric (17:0) and arachidic (20:0) acids increased. It was found that freeze-dried cooked beans, prepared from raw seed beans, kept 2.5 years at 10 °C, have practically the same fatty acid composition as freeze-dried cooked beans 0.5 year after harvesting.     

Bypassing the rumen in dairy ewes: the reticular groove reflex vs. calcium soap of olive fatty acids

A 3 x 3 Latin Square experiment was designed to compare 2 ways of bypassing the effects of the rumen with olive oil fatty acids in 'Manchega' dairy ewes. Treatments were a control diet, CaOFA (control diet plus 45 g of olive fatty acids as calcium soap), and OO (control plus 45 g/d of olive fatty acids as olive oil emulsified in skim milk) and bottle-fed to animals trained to maintain the reticular groove reflex). No differences were found in milk, protein, and lactose yields, but fat yield and milk fat content were greater in treatments with added fat (CaOFA and OO). Content of short- and medium-chain fatty acids in milk fat was greater for control treatment than for the other 2 groups, the yield of these fatty acids being similar for all 3 diets, except that of C12:0, which was greater for the control treatment. Content and yield of C18:0 and isomers of C18:1 others than oleic acid were greater in milk from the CaOFA diet than from the other 2 diets. Oleic acid content and yield were greater in milk after OO treatment (23.9% and 16.8 g/d, respectively), intermediate after CaOFA treatment (19.2% and 13.8 g/d, respectively), and lower after control diet (10.7% and 6.52 g/d, respectively). Linoleic acid yield and content were greater in ewes fed the OO diet than in those on the other 2 diets, both of which showed similar data. All these changes indicated that the "protected" olive fatty acids (as calcium soap) were severely affected by the rumen environment and that the use of the reticular groove reflex seems to be a more effective way of bypassing the rumen in adult lactating dairy ewes.     

Changes in fatty acids and polar material of restructured low-fat or walnut-added steaks pan-fried in olive oil

The study aims to determine the influence of pan-frying on the fatty acid composition and fat content and alteration of functional restructured beef steaks. Low-fat (L, 2% fat), 20% walnut-added (W, 13% fat) and medium fat (M, 13% fat) steaks were prepared and fried in extra virgin olive oil. Pan-frying increased fat in L and W steaks and decreased it in M ones. Raw L and M steaks showed similar fatty acid profiles while W ones contained a lower percentage of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) but a higher percentage of polyunsaturated fatty acids (PUFA). The fatty acid profile of fried steaks was between that of the raw steaks and olive oil. Several fatty acids (g fatty acid/100 g edible steaks) were affected (p < 0.001) by the frying × meat-formulation interaction. Linoleic and linolenic acid contents did not decrease in fried W steaks, but decreased (p < 0.05) when data were expressed on a dry matter basis.Frying increased SFA, MUFA and ω-6 PUFA contents in L samples while it decreased SFA and increased ω-6 PUFA in M steaks. Before and after frying, W steaks had atherogenic and thrombogenic indexes at least three times lower than their counterparts. Both indexes decreased in fried L samples while only the AI in M ones. Polar material content (PM) increased only in L samples. No relevant differences were found between PM of the fried steaks and that of their corresponding used oils. Results suggest that pan-frying improves the fatty acid composition of L and M steaks with minor changes in PM. The high retention of lipids observed in the W samples permits consumption of ω-3 PUFA- and ω-6 PUFA-enriched meat with a very low content of alteration compounds.     

11种品牌玉米油脂肪酸及异构体的主成分分析

对市售的11种品牌玉米油开展了脂肪酸(包括脂肪酸及其异构体)组成与含量的调查研究。采用气相色谱技术,结合主成分分析法,分析了不同品牌玉米油中脂肪酸的差异性和相关性。结果表明,11种品牌玉米油中共鉴定出19种脂肪酸,包括7种饱和脂肪酸,5种不饱和脂肪酸,6种反式脂肪酸(TFAs)和1种共轭亚油酸(t,t-CLAs),平均含量分别为14.18×10~(-2) g/g,80.32×10~(-2) g/g,1.47×10~(-2) g/g和0.23×10~(-2) g/g;其中,亚油酸(C18:2-9c12c)、油酸(C18:1-9c)和棕榈酸(C16:0)依次是玉米油中含量最多的3种脂肪酸;不同品牌玉米油中脂肪酸含量存在显著性差异(p0.05)。主成分分析揭示了不同品牌玉米油在脂肪酸含量上的相似性、差异性及脂肪酸之间相关程度,TFAs和CLAs正相关程度高。本研究为评价市售玉米油脂肪酸品质特征提供了较为全面的数据支撑。