海南油棕果肉中脂肪酸的成分分析

用乙醚萃取海南油棕果肉中的油脂,油脂中的脂肪酸采用氢氧化钾-甲醇溶液进行甲酯化后,利用气相色谱-质谱联用技术（GC—MS）对其中的脂肪酸成分进行分析。结果分离鉴定出4种脂肪酸成分,它们分别是棕榈酸（45．62％）、油酸（37．70％）、亚油酸（8．39％）、硬脂酸（8．29％）。其中不饱和脂肪酸高达46％以上,有进一步开发利用的潜力。     

Simultaneous Determination of Free Fatty Acids and Esterified Fatty Acids in Rice Oil by Gas Chromatography

Free fatty acids (FFA) in crude rice oil were selectively and stoichiometrically derivatized to fatty acid N,N-dimethylamides (FADMA) by catalytic condensation at 45 °C, and then esterified fatty acids (eFA) were directly converted to fatty acid methyl esters (FAME) at 37 °C. The mixture of FADMA and FAME formed in a single test tube was injected into the capillary column of a gas chromatograph (GC). No mutual contamination occurred between FFA and eFA, and reliability of the method was confirmed by comparison between GC data obtained by this method and by a conventional isolation method. The advantages of the present method are that no FFA isolation procedures are required, the reactions proceed under mild temperature conditions, and FFA and eFA can be analyzed simultaneously by GC.     

油价暴涨，催生脂肪酸甲酯磺酸盐（MES）走向市场

介绍脂肪酸甲酯磺酸盐(MES)的可生物降解、绿色环保以及良好的洗涤性等优点,同时概述了我国的MES生产企业现状。阐述了当前MES的生产技术难点,及国内外的生产技术现状。2005年,国际原油价格暴涨,催生以棕榈油为原料的MES走向市场。     

Benzyl and Methyl Fatty Hydroxamic Acids Based on Palm Kernel Oil as Chelating Agent for Liquid-Liquid Iron(III) Extraction

Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract iron(III) at pH 1.9 were realized effectively with a high percentage of extraction (97.2% and 98.1% for MFHAs and BFHAs, respectively). The presence of a large amount of Mg(II), Ni(II), Al(III), Mn(II) and Co(II) ions did affect the iron(III) extraction. Finally stripping studies for recovering iron(III) from organic phase (Fe-MFHs or Fe-BFHs dissolved in hexane) were carried out at various concentrations of HCl, HNO(3) and H(2)SO(4). The results showed that the desired acid for recovery of iron(III) was 5 M HCl and quantitative recovery of iron(III) was achieved from Fe(III)-MFHs and Fe(III)-BFHs solutions in hexane containing 5 mg/L of Fe(III).     

Interfacial Tensions of Ethoxylated Fatty Acid Methyl Ester Solutions Against Crude Oil

The dynamic interfacial tension (IFT) of ethoxylated fatty acid methyl ester solutions against n‐alkanes, kerosene, and diluted heavy oil have been investigated by spinning drop interfacial tensiometry. The influences of ethylene oxide (EO) groups and alkyl chain length on IFT were investigated. The experiment results show that the water solubility decreases with an increase in alkyl chain length or a decrease in EO groups. The ability to lower the interfacial tension against hydrocarbons improves with both increasing alkyl chain length and EO group at the best hydrophilic‐lipophilic balance, which can be attributed to the enhancement of the interfacial hydrophobic interactions and the rearrangement of interfacial surfactant molecules. The mixed adsorption of surfactant molecules and surface‐active components may reduce IFT to a lower value. C₁₈=E₃ shows the best synergism with surface‐active components. However, the IFT values against pure crude oil are obviously higher than those against hydrocarbons, which may be caused by the nature of heavy oil.     

固体酸催化废油酯制备脂肪酸丁酯

研究以废油酯为原料在固体酸催化作用下与丁醇酯交换反应制备脂肪酸丁酯的过程,采用气相色谱对脂肪酸丁酯的含量进行分析。考察了醇油摩尔比、催化剂用量、反应温度和反应时间对酯化反应转化率的影响。结果表明,该反应的最适宜工艺条件为：醇油摩尔比16∶1,催化剂用量1.2%,反应温度115℃,反应时间4 h。废油酯在最优工艺条件下,经过酯交换反应得到的转化率超过83%。     

连续减压精馏分离椰子油脂肪酸的模拟研究

文章利用Aspen Plus化工模拟软件中的严格计算法RadFrac单元操作模块对椰子油脂肪酸进行了连续减压精馏分离模拟。考察了塔板数、回流比、进料位置对分离效果的影响。结果表明:采用两个精馏塔B1塔和B2塔串联操作,操作压强为2500 Pa(绝压),原料进料质量流率20 kg/h,B1塔理论板数为15,第8块塔板进料,回流比为2(体积比),塔顶可得到产物辛酸的质量流率为8.675 kg/h,质量分数可达98.58%及回收率可达99.83%。塔底物料经B2进一步分离,B2塔板数为15,第9块塔板进料,回流比为1,塔顶可得到产物癸酸的质量流率为10.86 kg/h,质量分数为99.79%及回收率为98.81%。模拟结果对实验研究及工业化生产具有指导意义。     

分子蒸馏富集海狗油中多不饱和脂肪酸

海狗油中富含多不饱和脂肪酸,如二十碳五烯酸(EPA)、二十二碳五烯酸(DPA)、二十二碳六烯酸(DHA)等。用分子蒸馏法对海狗油中多不饱和脂肪酸进行富集,通过控制适宜的温度和压力等条件,得到较为满意的分离效果。当进料速率为80 mL/h,预热温度为80℃,刮膜器转速为250r/min,蒸馏温度为120℃,压力为15 Pa时,经过一级分子蒸馏,得到EPA、DPA和DHA的总含量为54.86%(质量分数)的海狗油产品,收率为92.7%,并用气相色谱法测定了产品的脂肪酸组成。     

蒲葵根中脂肪油的GC-MS联用分析

采用GC—MS联用技术首次分析了蒲葵根中脂肪油的组成，共分离出36个峰，并鉴定出其中的23种化合物。该脂肪油的主要成分为月桂酸乙酯、十六烷酸乙酯、亚麻酸、亚油酸乙酯、9—十八碳烯酸乙酯等。为蒲葵根资源的开发利用提供了科学依据。     

Auxiliary Degumming and Pressurized High Temperature Water Washing to Mitigate the Formation of Monochloropropanediols in Palm Oil

This study reports the benefits of auxiliary degumming (Aux.D) and pressurized high temperature (165 °C) water washing (PHTW) to mitigate the formation of monochloropropanediols (MCPD) during labscale physical refining of palm oil. Water-based degumming in combination with bleaching and deodorization are performed as the selected physical refining process. The mitigation concepts Aux.D and PHTW are integrated into the refining protocol and the ultimately observed MCPD levels in the fully refined oils are determined. Aux.D is performed by extracting the hydratable gum from pressed sunflower oil and using it as a degumming agent to further purify palm oil that has been previously subjected to centrifugation and water degumming. This approach enables the mitigation of 3-MCPD from the water washed reference 2.4–0.9 mg kg⁻¹ in ampoules. Even stronger mitigation is obtained when Aux.D is combined with bleaching and executed twice allowing a mitigation from the reference 1.9–0.6 mg kg⁻¹, in ampoules. PHTW is shown to decrease the 3-MCPD content of the refined oil from the reference 2.4–1 mg kg⁻¹, in ampoules and when combined with bleaching and executed twice showing a decrease from the reference 1.9–0.9 mg kg⁻¹. Practical applications: The benefits of these mitigation concepts are confirmed both in sealed ampoule tests and in deodorizer experiments at the lab scale. A combined application of Aux.D or PHTW with physical refining may represent new insights that can help to potentially further mitigate the formation of MCPD in physically refined palm oil beyond the limits achievable with current refining practices.     

核桃油中主要脂肪酸的毛细管柱气相色谱分析

采用毛细管柱气相色谱程序升温的方法 ,将核桃油用正己烷稀释后直接进样 ,对 5种主要脂肪酸进行定性定量分析。 5种主要脂肪酸占出峰物质总量的 97%。     

鱼油不饱和脂肪酸的自由基氧化规律

从东海小杂鱼鱼油中鉴定出43种脂肪酸,主要16种脂肪酸占总脂肪酸95．01％。测定了鱼油加入自由基后在不同的时间及不同光照条件下的脂肪酸的氧化规律,并进行分析发现无论在光照还是避光条件下所有不饱和脂肪酸都随着时间的推移,含量都有下降的趋势,说明不断的被氧化,特别是EPA、DHA被氧化的更快。在光照条件下鱼油中的脂肪酸氧化比在避光条件下要快。在实验过程中,通过在鱼油加入自由基后再加入不同的抗氧化剂,利用TBA值的测定,筛选出对鱼油中的脂肪酸氧化有较好的抗氧化性的各种抗氧化剂的有效浓度。同时可以发现4-己雷琐辛的抗氧化性最强,由于此实验中用的TBHQ是食品级的,因此BHA的抗氧化性比TBHQ强。并且对鱼油在添加抗氧化剂前后脂肪酸的自由基氧化规律进行比较。     

Fe2(SO4)3/C催化餐饮废油脂中游离脂肪酸酯化反应的动力学

The esterification of free fatty acids(FFA) in waste cooking oil with methanol in the presence of Fe₂(SO₄)₃/C(ferric sulfate/active carbon) catalyst was studied.The effects of different temperature,methanol/FFA mole ratio and amount of catalyst on the conversion of FFA were investigated.The results demonstrated that under optimal esterification conditions the final acid value of the resultant system can be reduced to ～1(mg KOH)·g^-1,which met fully the requirements in post-treatment for efficient separation of glycerin and biodiesel.The kinetics of the esterification were also investigated under different temperatures.The results indicated that the rate-control step could be attributed to the surface reaction and the esterification processes can be well-depicted by the as-calculated kinetic formula in the range of the experimental conditions.     

Alteration of Endogenous Fatty Acids Profile and Lipid Metabolism in Rats Caused by a High-Colleseed Oil and a High-Sunflower Oil Diet

Dietary fat has an important influence on mammalian lipid homeostasis. However, the relationship between dietary fat types and endogenous fatty acids (FAs) in organs as well as lipid homeostasis remains unclear enough. In this study, rats are randomly divided into a control group (CN), a high-colleseed oil group (COG), and a high-sunflower oil group (SOG). FAs profile in liver and visceral fats of rats in two high-fat (HF) diet groups is compared with that in CN. Oleic, γ-linolenic, eicosadienoic, and arachidonic acid accumulate in COG liver or visceral fats, but the levels of linoleic, eicosadienoic, docosanoic, and dihomo-γ-linolenic acid decrease in COG visceral fats. However, these FAs levels increased in SOG liver or visceral fats except dihomo-γ-linolenic and arachidonic acid which changed insignificantly. The trend of initial upregulation and then downregulation of lipid metabolism-related genes expression is noted in COG liver, including stearoyl-CoA desaturase. Upregulation of adiponectin (ADPN) expression in visceral fats and downregulation of ADPN receptor 2 (Adipo-R2) expression in livers of both HF groups are observed. Correlation analysis revealed positive correlations between specific FAs content and ADPN expression level. Negative correlations are observed between Adipo-R2 expression and the content of oleic, linoleic, and γ-linolenic acid in the SOG liver. Practical applications: Dietary fat not only provides energy but is also associated with lipid homeostasis. In this work, the authors investigate the distribution of fatty acids (FAs) in vivo and their influence on genes related to lipid metabolism induced by diets enriched in oleic acid or linoleic acid. The study suggests that dietary fats modulate lipid homeostasis not only by regulating endogenous FAs levels but also by affecting the expression of genes related to lipid metabolism. This study may support the research in lipid nutrition and rational intake of dietary fat.     

香榧种子含油量及脂肪酸组成对比研究

为探究不同品种香榧种子含油量及组成的差异,对同一产地不同品种的11种香榧（旋纹榧、茄榧、大圆榧、米榧、象牙榧、芝麻榧、普通榧、木榧、小圆榧、炭盆榧和寸金榧）种子的含油量以及种子油脂肪酸组成进行了对比研究,结果表明：不同品种的香榧种子含油量及种子油脂肪酸类型都表现出明显差异。11种不同香榧种子含油量约2%~14%,普通榧最高（13.4%）,炭盆榧最低（2.2%）;脂肪酸种类最少8个,最多13个（寸金榧和木榧）。香榧种子油以不饱和脂肪酸为主,其总量超过66%。普通榧不饱和脂肪酸总量达到85.87%,其中主要成分油酸、亚油酸总量超过72%。所有品种的香榧种子油都含有超过6.90%的特殊脂肪酸金松酸,而且以普通榧中含量最高,达到10.41%。     

植物油制备生物柴油的研究

分别以菜籽油、大豆油以及芸香籽油为原料，采用碱催化酯交换法制备了脂肪酸甲酯即生物柴油。结果表明，用碱催化酯交换法制备脂肪酸甲酯，原料的酸价低于1．5mgKOH／g时能够保证较高的脂肪酸甲酯收率，采用酸催化预酯化法对高酸价的油脂原料进行脱酸效果比较显著。浓硫酸不仅是油脂预酯化脱酸反应的催化剂，也是油脂与甲醇进行酯交换反应的催化剂，但与甲醇钠等碱性催化剂相比，相同条件下的酯交换反应转化率低。采用减压蒸馏的方法提纯生物柴油，在0．098MPa的真空度下应控制其馏出温度不超过240℃。     

Rapid Determination of Free Fatty Acid in Extra Virgin Olive Oil by Raman Spectroscopy and Multivariate Analysis

We introduce a visible Raman spectroscopic method for determining the free fatty acid (FFA) content of extra virgin olive oil with the aid of multivariate analysis. Oleic acid was used to increase the FFA content in extra virgin olive oil up to 0.80% in order to extend the calibration span. For calibration purposes, titration was carried out to determine the concentration of FFA for the investigated oil samples. As calibration model for the FFA content (FFA%), a partial least squares (PLS) regression was applied. The accuracy of the Raman calibration model was estimated using the root mean square error (RMSE) of calibration and validation and the correlation coefficient (R ²) between actual and predicted values. The calibration curve of actual FFA% obtained by titration versus predicted values based on Raman spectra was established for different spectral regions. The spectral window (945–1600 cm⁻¹), which includes carotenoid bands, was found to be a useful fingerprint region being statistically significant for the prediction of the FFA%. High R ² and small RMSE values for calibration and validation could be obtained, respectively.     

Free Fatty Acids in Commercial Krill Oils: Concentrations,Compositions, and Implications for Oxidative Stability

The concentrations and pro-oxidative effects of free fatty acids in commercial krill oil are not well defined. We now report that krill oil free fatty acids account for 2–13% of total lipids in commercial krill oil (n = 8) that these compounds are enriched in eicosapentaenoic acid (+7.1%) and docosahexaenoic acid (+6.3%) relative to whole oils; and that this composition make them highly pro-oxidizing in marine triacylglycerol oils, but not in krill oil, which derives oxidative stability from both its phospholipids, and neutral lipids (the latter because of astaxanthin). Specific fatty acid esterification patterns showed that krill oil free fatty acids predominantly (88–93%) originated from phospholipids, mainly from the sn-2 position, which was eight-fold more hydrolyzed than the sn-1 position. Lipolysis was not ongoing in stored oils. Adding small amounts of krill oil (1–5%) to marine triacylglycerol oils significantly increased their oxidative stability and also their resistance to free fatty acid-mediated pro-oxidative effects.     

载银介孔SBA-15吸附剂的制备及其对脂肪酸甲酯的吸附研究

以介孔分子筛SBA-15作为载体,在3-氨基丙基三乙氧基硅烷(APTS)对SBA-15表面修饰的基础上负载银离子制备Ag⁺-APTS/SBA-15吸附剂,采用氮气吸附-脱附、X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、透射电镜(TEM)、扫描电镜-能谱(SEM-EDS)对吸附剂进行表征,并将吸附剂应用于混合脂肪酸甲酯的分离以考察其吸附性能。氮气吸附-脱附、XRD和TEM分析结果可以看出,制备的吸附剂具有规则有序孔道结构;FT-IR数据显示,介孔SBA-15表面被APTS成功修饰;SEM-EDS结果表明,银离子成功负载到载体SBA-15上;对混合脂肪酸甲酯吸附研究表明,该吸附剂对不饱和脂肪酸甲酯(UFAMEs)吸附效果较好,且随着银离子负载量的增加以及UFAMEs双键数的增多,吸附效果增强;当银离子负载量为25%时,吸附剂对亚麻酸甲酯吸附率高达53.47%。     

Purification of Free DHA by Selective Esterification of Fatty Acids from Tuna Oil Catalyzed by Rhizopus oryzae Lipase

Tuna fish oil contains 25–30 % docosahexaenoic acid (DHA) and is one of the richest sources of DHA. The present paper investigates the enrichment of DHA by selective esterification of fatty acids obtained from hydrolysis of tuna fish oil catalyzed by Rhizopus oryzae lipase (ROL). The fatty acid mixture obtained after hydrolysis of tuna fish oil, referred to as tuna-FFA contained 26 % DHA. For purification/concentration of DHA in free fatty acids, selective esterification of the fatty acid mixtures with butanol was carried out using ROL in a water-organic solvent system. The best reaction parameters found in this study were pH 7, temperature 35 °C, agitation speed 800 rpm and a fatty acid to solvent (iso-octane) ratio of 1:1.32 (w/v). Also, the effects of other parameters such as type of alcohol, type of enzyme, alcohol to fatty acid ratio, enzyme to fatty acid ratio were studied to determine the most suitable reaction conditions. Exactly 76.2 % of tuna-FFA was esterified in 24 h, under the most suitable reaction conditions and the DHA content in the fatty acid fraction rose from 26 to 86.9 % with 80 % recovery of DHA, after selective esterification. The DHA content of fatty acids in butyl esters was found to be 13.6 %.