米糠油及其脱臭馏出物中生育酚和生育三烯酚的分析检测

对米糠油及其脱臭馏出物中生育酚及生育三烯酚含量进行检测分析,结果表明,米糠来源和米糠油精炼工艺对米糠油及其脱臭馏出物中α、β、γ、δ-生育酚和生育三烯酚的含量有显著影响。米糠毛油中生育三烯酚占维生素E总量的60%～70%,脱臭馏出物中生育三烯酚占维生素E总量的25%～40%,米糠油脱臭馏出物维生素E总量中生育三烯酚的含量较米糠毛油有较大的损失。通过对米糠油脱臭馏出物不皂化物的分析检测可知,米糠油脱臭馏出物中主要甾醇的种类为豆甾醇、菜油甾醇、谷甾醇,总甾醇含量很少,仅为0.32%;除此之外,还有少量日耳曼甾醇、羊毛甾醇、3,5-二烯豆甾烷等。     

脱臭过程中保留米糠油中植物甾醇的工艺优化

采用氮气蒸馏法进行米糠油的脱臭,研究了脱臭温度、脱臭时间以及氮气流速对脱臭米糠油中植物甾醇含量的影响。结果表明,在保证得到高品质米糠油的前提下,最大程度保留脱臭油中植物甾醇的优化工艺条件为:脱臭温度260℃,脱臭时间120 min,氮气流速0.12 m3/h。在最优工艺条件下,植物甾醇保留率(相对于脱色油)为83.38%,米糠油酸值(KOH)为0.25 mg/g,精炼率为93.01%。同时发现,脱臭前后米糠油中植物甾醇的主要组成成分没有变化,均为豆甾醇、菜油甾醇和β-谷甾醇。     

植物甾酸和甾烷醇的生理功能

<正>在精炼植物油时脱胶产生油脚和脱臭副产馏出物内富含植物甾醇,这些副产物系为制取植物甾醇良好来源;所含植物甾醇主要有β-谷甾醇、菜油甾醇、豆甾醇等,其中,尤以β-谷甾醇量最丰。其化学结构与胆固醇相似,但在侧链上有部分不同。另外,与植物甾醇共存的还有一种天然微量的双链饱和型甾醇,即甾烷醇。由于从植物甾醇内难以分离精制甾烷醇,一般是通过将植物甾醇加氢饱和而成。制取β-谷甾烷醇以β-谷甾醇、豆甾醇为原料,菜油甾烷醇以菜油甾醇为原料。     

油脂加工副产物—脱臭馏出物的综合利用

油脂脱臭馏出物是植物油精炼脱臭时的副产物,含有多种活性成分,提取、纯化和应用这些活性成分已成为研究的热点。为了促进脱臭馏出物的综合开发利用,本文综述植物油脱臭馏出物中天然VE、植物甾醇、角鲨烯、脂肪酸甲酯等多种活性成分的理化性质、提取纯化方法及应用延伸。结果表明,植物油脱臭馏出物是天然VE的较好来源,且不同来源的脱臭馏出物中提取的天然VE的组成有所不同。从脱臭馏出物中提取VE多采用酯化法、尿素络合法、酶法、溶剂萃取法、分子蒸馏法、离子交换法、吸附法、柱层析法、超临界萃取法等两种或多种方法的组合形式进行富集和纯化。目前市场上的天然VE的品种大致分为四类:混合生育酚、天然α-生育酚、天然α-生育酚衍生物、混合生育酚/天然α-生育酚粉末等。从脱臭馏出物中提取植物甾醇通常分两步,先从原料中提取粗甾醇,然后采用溶剂结晶、络合法、吸附法、酶法等精制方法精制甾醇。植物甾醇的应用延伸包括水溶性植物甾醇、谷甾醇、豆甾醇、4AD、ADD和多种甾体皮质激素药物。从脱臭馏出物中提取角鲨烯通常是先提取不皂化物,然后从不皂化物中采用超临界CO2萃取、色谱分离、分子蒸馏法、吸附分离法等进一步提取角鲨烯。脱臭馏出物中脂肪酸的含量一般在25%~75%之间,这些脂肪酸在制备天然VE和植物甾醇的过程中转化为脂肪酸甲酯,而以脂肪酸甲酯为原料可制备生物柴油、单双甘油酯、环氧脂肪酸甲酯、表面活性剂和洗涤剂等产品,使得油脂脱臭馏出物得到进一步的综合利用。     

气相色谱法同时快速测定大豆油脱臭馏出物中的生育酚、植物甾醇和角鲨烯含量

摘要：建立了可以同时定量分析大豆油脱臭馏出物中生育酚（α-生育酚、(β+γ)-生育酚、δ-生育酚）、植物甾醇（菜籽甾醇、菜油甾醇、豆甾醇、β-谷甾醇）和角鲨烯含量的气相色谱检测方法。以十六酸十六醇酯为内标物质,样品直接溶解在内标溶液中,采用HP-1色谱柱分离,以内标法定量。结果表明：各组分之间分离度良好,生育酚、植物甾醇和角鲨烯分别在0.4~6.4 mg/mL、0.5~8.0 mg/mL、0.4~4.0 mg/mL范围内呈现良好的线性关系,R2均大于等于0.999,平均加标回收率分别为95.38%~102.78%、96.40%~101.24%、96.14%~104.43%,相对标准偏差均小于10%,检出限分别为0.08、0.15、0.05 mg/L。该方法前处理简单、重复性好、灵敏度高、结果准确可靠,可应用于大豆油脱臭馏出物中生育酚、植物甾醇、角鲨烯含量的同时测定。     

米糠油脱臭馏出物乙酯化工艺条件研究

为综合利用米糠油脱臭馏出物提取生育酚和生育三烯酚,同时得到可用于医药和食品工业的脂肪酸乙酯,本文研究米糠油脱臭馏出物乙酯化最佳工艺条件。试验结果表明,米糠油脱臭馏出物乙酯化的最佳工艺条件为：脂肪酸：乙醇（mol/mol）1∶5;反应时间2.5h;温度75℃;浓硫酸：原料（wt%）3%。在该条件下,脂肪酸乙酯化率达到97.02%,VE保存率达98.48%。     

植物甾醇HPLC-ELSD检测方法研究

建立了反相高效液相色谱-蒸发光散射检测器(HPLC-ELSD)测定植物甾醇含量的方法.结果表明以甲醇-乙腈(75:25,V:V)为流动相,流速1.0 mL/min,可有效分离混合植物甾醇中的豆甾醇、菜油甾醇和β-谷甾醇,它们的标准偏差分别为0.005 7、0.005 6、0.006 6;平均回收率分别为98.2%、101.3%、101.8%;线性范围(线性相关系数)分别为0.016～0.46 mg/mL(r=0.996 8)、0.05～0.45 mg/mL(r=0.999)、0.022～0.45mg/mL(r=0.994 9).用该方法成功检测了豆油脱臭馏出物的维生素E提余物中的植物甾醇.     

豆甾二烯用于特级初榨橄榄油掺假检测的研究

研究了利用豆甾二烯进行特级初榨橄榄油的掺假检测,考察了在特级初榨橄榄油中掺入不同比例油橄榄果渣油、榛子油、葵花籽油、大豆油、玉米油、花生油、米糠油、棕榈油和核桃油,采用高效液相色谱法(HPLC)测定掺和油中的3,5-豆甾二烯含量。植物油样品用石油醚溶解,过硅胶柱净化,C30柱分离,乙腈/叔丁基甲醚(75∶25,V/V)作流动相,紫外检测波长235nm。结果表明,本方法具有良好的回收率及精密度,3,5-豆甾二烯是特级初榨橄榄油掺假鉴别的一个十分重要的特征性指标,本方法能够鉴别出了特级初榨橄榄油中掺入0.3%油橄榄果渣油、0.5%榛子油、2.1%葵花籽油、0.5%大豆油、0.3%玉米油、1.5%花生油、0.2%米糠油、0.6%棕榈油和0.6%核桃油。     

提取植物甾醇的试验研究

大豆油脱臭馏出物是油脂精炼过程中得到的副产物。本研究通过高效液相色谱法定性和定量分析，测定原料中甾醇的含量为9,55％．其中菜油甾醇＋豆甾醇的含量为5．147％，β-谷甾醇的含量为4．403％；通过正交试验，进一步确定了甾醇精制的最佳工艺每件为料液比（粗甾醇质量：乙醇体积）1：20，养晶终止温度-5℃．养晶时间16h。精制甾醇的纯度可以达到95％，得率达到90％。     

硫酸对大豆油脱臭馏出物中天然VE和植物甾醇的影响

作为脂肪酸酯化催化剂,浓硫酸与固体酸和酯化酶相比,具有成本低,效率高,操作简单等特点。因此,浓硫酸在大豆油脱臭馏出物提取天然VE生产过程中广泛用于脂肪酸的酯化工艺。本研究考察了以浓硫酸作为天然维生素E酯化工艺的催化剂,在反应和后处理过程中硫酸对VE和植物甾醇收率的影响,并取得了一些非常有意义的发现。大豆油脱臭馏出物中天然VE包括α、β、γ、δ-生育酚,植物甾醇主要包含谷甾醇、豆甾醇、菜油甾醇和菜籽甾醇。实验结果显示,硫酸浓度和温度对大豆油脱臭馏出物中天然VE和植物甾醇的影响显著。硫酸浓度和温度越高对天然VE和植物甾醇破坏越快。同时发现天然VE中α-生育酚的耐酸性显著好于其他三种生育酚。在生产过程中为了减小硫酸对天然VE和植物甾醇的破坏,应合理控制硫酸使用条件。     

Study on the Chemical Nature of Sterols contained in Bulgarian Sunflower Oil

The free sterols, the sterol esters and the sterol glycosides of the crude sunflower oil as well as those of the technical lecithin, the pitch and the deodorizer distillate of the latter oil were isolated by preparative TLC. The nature of sterols contained in the isolated sterol derivatives was elucidated by GLC and combined GLC-MS. Major sterols of all examined sterol fractions are sitosterol, campesterol and stigmasterol, the amount of sitosterol being prevalent. Unknown sterol with a molecular weight of 4²⁸ is present in sterols of the crude oil and the deodorizer distillate. Sterols of the deodorizer distillate contain an unknown sterol with a molecular weight of 430. Stigmasterol is present in the sterol fraction of the deodorizer distillate in high amounts. It was established that Δ⁷-sterols of the crude oil occur only in esterified form. The hydrolysis of the sterol derivatives in acid medium leads to dehydration products known as steroid dienes and disteroid ethers. Hydrolysis without dehydration was achieved by enzyme preparations. Some sterols of the crude oil were esterified with the same higher fatty acids contained in the glycerides of the sunflower oil.     

脱酸米糠毛油品质对吸附脱色综合效果的影响

采用碱炼脱酸和水蒸汽蒸馏脱酸两种不同脱酸工艺所得米糠油进行吸附脱色试验,以米糠油脱色率及谷维素、甾醇、维生素E等营养成分保留率和反式脂肪酸生成量作为考察指标,分析研究待脱色米糠油品质对吸附脱色综合效果的。结果显示,在脱色率、VE保留率和反式酸含量方面碱炼脱酸米糠油的综合脱色效果优于水蒸汽蒸馏脱酸米糠油。碱炼脱酸米糠油的最佳吸附脱色条件为:凹凸棒石为吸附剂,用影响量为油重的4%,脱色时间30 min,脱色温度110℃。在最佳工艺条件下,测得米糠油脱色率为75.08%,脱色米糠油的色泽为Y35、R2.1(罗维朋比色槽25.4 mm),满足国标三级米糠油色泽要求;谷维素保留率为88.89%(脱色前后谷维素含量分别为0.90%、0.80%、),甾醇保留率为73.87%(脱色前后甾醇含量分别为2.32%、1.71%),维生素E保留率为82.90%(脱色前后维生素E含量分别为50.57 mg/100 g、41.92 mg/100 g);与水蒸汽蒸馏脱酸米糠油相比,相同脱色条件下,脱色率提高7.84%,维生素E保留率提高7.64%,但谷维素保留率下降4.74%,甾醇保留率下降4.58%。脱色前后碱炼脱酸米糠油中未检出反式酸,水蒸汽蒸馏脱酸米糠油中反式酸含量为0.40%,脱色后反式酸含量增加了0.02%。虽然谷维素和甾醇的保留率相对降低,但两者的保留率仍达到了88.89%、73.87%,脱色油中两者含量分别为0.80%、1.71%,单就脱色过程而言,营养成分保留率还是很高的。     

Sterol composition of Bulgarian soya and corn oils

The free sterols, the sterol esters and the sterol glycosides of the raw soya and corn oils as well as those of the technical lecithin and the deodorizer distillated of the latter oils were isolated by preparative TLC. The composition of each of the isolated sterol derivatives was determined by GLC and MS. Sitosterol, campesterol, stigmasterol and an unknown sterol with a molecular weight of 428 are contained in almost all of the examined fractions of the soya oil and its refinement byproducts. Dehydrocampesterol is present in the free sterols of the raw soya oil and the soya lecithin. Stigmasterol is contained in the soya deodorizer distillate in high amounts. It was established that cholesterol was present in the sterol esters of the raw soya oil high amounts. Delta7-stigmastenol occurs only in the sterol esters of the latter oil. Sitosterol, campesterol and stimgasterol are the main components of all sterol fractions of the corn oil and its refinement products. Dehydrocampesterol and unknown sterols with molecular weights of 428 are present in the free sterols of the raw corn oil. Some sterol glycosides of the soya and corn lecithin are esterified with the same major fatty acid components of the glycerides, palmitic acid being the main one. The fatty acid compositon of sterol esters of the raw soya and corn oil roughly corresponds to the fatty acid composition of oils.     

以稻米油为基油制备稻米调和油及其煎炸性能的研究

对稻米油、稻米调和油、添加0.02%迷迭香提取物的稻米调和油和添加0.06%茶多酚的稻米调和油4种煎炸油进行土豆条连续煎炸试验,对比4种煎炸油在煎炸过程中的极性组分、脂肪酸组成、维生素E、甾醇、谷维素、反式脂肪酸(TFA)、3-氯丙醇酯(3-MCPD酯)和苯并芘含量变化,综合评估其煎炸性能。结果表明:稻米油、稻米调和油、添加迷迭香提取物的稻米调和油和添加茶多酚的稻米调和油的极性组分含量分别在煎炸10、14、16 h和14 h超过国家标准;稻米调和油的谷维素保留率均优于稻米油;添加迷迭香提取物有利于维生素E和谷维素的保留;添加茶多酚有利于甾醇的保留;反式脂肪酸和苯并芘的含量均未超过国家标准限值。     

Isolation of sterols from sunflower oil deodorizer distillate

A new method for isolating sterols from sunflower oil deodorizer distillate (DOD) was developed. The most salient feature of which is that, unlike most alternatives, it requires no distillation. Briefly, the method uses methanol in the presence of p-toluenesulphonic acid as catalyst to convert free fatty acids and acyl glycerides in DOD into fatty acid methyl esters (FAMEs). The resulting glycerin and excess reagents are removed by washing with water and, finally, the product is cooled in the absence of solvents to obtain sterols in 92 ± 2% purity.     

植物甾醇分析和纯化

对不同脱臭馏出物生产的甾醇粗制品的成分进行了检测,并对不同溶剂纯化甾醇粗制品的效果进行了分析.结果表明,不同脱臭馏出物来源的甾醇粗制品,不仅杂质含量不同,且杂质的种类也不同.以大豆油脱臭馏出物生产的甾醇粗制品中,其杂质主要是蜡,易采用正己烷和乙酸乙酯进行重结晶精制,精制甾醇的纯度可达96%以上.以菜籽油脱臭馏出物生产的甾醇粗制品中,杂质主要是长链烷烃,易采用正己烷进行重结晶精制,精制甾醇的纯度也可达96%以上.     

皂化工艺对生育酚含量及其异构体变化影响研究

采用皂化工艺对从大豆油脱臭馏出物中脂肪酸进行脱除,研究不同相中皂化过程对生育酚含 量影响,分析生育酚各异构体在皂化过程中损失。     

高甾醇含量热带假丝酵母细胞的培养条件研究

以大豆油脱臭馏出物为唯一碳源,研究了高产甾醇的热带假丝酵母（Candida tropicalis）1253细胞的培养条件。研究发现,无机氮源培养使得菌体甾醇含量显著高于有机氮源培养。当尿素与牛肉膏复合作为氮源时,菌体甾醇含量最高（7.55%）。最佳培养基配方为：脱臭馏出物50.0 g/L、尿素1.0 g/L、牛肉膏1.0 g/L、甘氨酸0.02 g/L、十二烷基苯磺酸钠0.5 g/L、MgSO4 0.1 g/L、K2HPO4 0.2 g/L、KH2PO4 0.2 g/L。最适培养条件为：初始pH 7.0、摇床转速200 r/min。采用上述最适的发酵条件,按10%（V/V）接种量接入热带假丝酵母1253种子液,30 ℃摇床振荡培养96 h。发酵结束后,经过测定,酵母细胞中甾醇含量为8.83%。     

The composition of lipids from rice hulls and from the surface of rice caryopsis

Samples of hulls, of whole and ground caryopsis and of bran obtained from the Brazilian rice variety IAC 1246, were extracted with hexane and the characteristics and composition of the corresponding lipids were determined. The lipids from rice hulls showed a four times higher content of unsaponifiable matter and of free fatty acids than those from rice bran and rice caryopsis. There were also differences in the fatty acid composition as evidenced by the presence of 2–3% of saturated C₂₂ and C₂₄ acids and a lower proportion of unsaturated acids in the rice hull lipids. On the other hand there was a close resemblance between the rice hull lipids and those on the surface of the caryopsis. Chromatographic analysis of the unsaponifiable matter of lipids from rice hulls and caryopsis surface disclosed the presence of hydrocarbons, alcohols and sterols in ascending order, the sterols consisting of about 50% of β-sitosterol, 20–40% of campesterol, 10–20% of stigmasterol and 2–3% of cholesterol. On the basis of the above results it was concluded that a preliminary solvent extraction of paddy rice in order to remove the waxy lipids from the hulls and the caryopsis surface would benefit the subsequent milling process and improve the quality of the brown rice and of crude rice bran oil.