食用植物油中矿物油污染物的分析进展

矿物油是C_(10)~C_(50)烃类化合物的总称,包括直链、支链和环状烷烃以及烷基取代芳烃两大类,化学成分复杂。食用植物油中普遍存在矿物油污染,含量达到1~1 000 mg/kg,矿物油污染来源广泛,涉及原料的采收、运输、加工和油脂的精炼、包装与储存等过程。植物油中干扰矿物油分析的成分较多,如甘油三酯、奇数碳正构烷烃、角鲨烯、甾烯、胡萝卜素等,需要采用适当方法排除。由于矿物油组成复杂,目前常用具有等碳响应的氢火焰离子化检测器分析含量,其中液相色谱-气相色谱联用是测定矿物油的理想技术。考虑到普及性问题,一些实验室开发了固相萃取结合大体积进样气相色谱法。综述了国内外近十年来食用植物油中矿物油的分析方法,以期为我国油脂及其相关产品中矿物油的检测工作提供参考。     

植物油中角鲨烯含量及其在油脂加工与使用过程中的变化

角鲨烯作为重要的脂溶性生理活性物质,常见于深海鱼肝油中。随着对食用油脂研究的深入,在橄榄油等植物油中也发现存在较高含量的角鲨烯。然而,植物油的过度加工通常会导致所含的角鲨烯大量损失,降低了油品的氧化稳定性和营养功能。介绍了角鲨烯的化学结构及其在常见植物油中的含量,进一步分析了其在制油和精炼过程中的含量变化,发现快速液压法、冷榨法和水酶法等低温制油方法可使油中的角鲨烯得到最大程度的保留,而脱臭是造成角鲨烯损失量最高的工段。研究发现煎炸对植物油中角鲨烯含量也有影响。随着煎炸时间的延长,油中角鲨烯含量不断减少。基于上述分析,认为开发并推广低温制油和适度精炼工艺,在保证出油率和控制危害物质至最低水平的基础上,可最大程度保留成品油中的角鲨烯含量,同时在油脂使用过程中控制好油温。     

Evaluation of polycyclic aromatic hydrocarbons content in different stages of soybean oils processing

A study was conducted in order to determine the levels of 13 polycyclic aromatic hydrocarbons (PAHs) in crude soybean oils produced in Brazil and to evaluate the influence of the refining process in their reduction. Analysis of intermediary products (neutralized, bleached and deodorized oils) showed that all compounds were reduced through refining (up to 88%). Neutralization and deodorization steps contributed effectively to the PAHs decrease. The mean total PAHs content in crude and deodorized oil samples ranged, respectively, from 10 to 316 and 3 to 69μg/kg. Since vegetable oils have been shown to be the major sources of PAHs in the diet, a monitoring program should be developed by the refining industries and the use of activated carbon during oil processing is highly recommended.     

混合油脂肪酸组成数学方程式在食用油模拟掺混检测中的验证

各种纯食用植物油都有其特定的脂肪酸组成,掺混后混合油与纯油的脂肪酸组成存在配比加和关系。对市场上常见的食用植物油花生油、大豆油、玉米油和油茶籽油中脂肪酸组成进行文献查询和统计分析,统计均值与食用植物油国标数据比较显示统计均值有很好的适用性,使用统计均值建立脂肪酸组成的数学方程式,通过模拟二元混合油和三元混合油体系进行验证,显示均有良好的相关性。该法可定量计算花生油、油茶籽油等混合其他低价食用植物油的添加比例,可作为一种判断掺伪油的定性和定量检测方法。     

Mitigation Strategies for the Reduction of 2‐ and 3‐MCPD Esters and Glycidyl Esters in the Vegetable Oil Processing Industry

The refining of vegetable oils leads to the formation of 2‐ and 3‐monochloropropane‐1,2‐diol esters (2‐ and 3‐MCPD‐E), and glycidyl esters (Gly‐E). A literature review was performed aiming to provide up‐to‐date knowledge on mitigation strategies during oil refining that can reduce the formation of these three processing contaminants. The review used the database Scopus and covered the period from 2009 to 2017. Most of the 18 papers dealt with palm oil and two papers with vegetable oil. Most studies focused on 3‐MCPD‐E, some on Gly‐E, and none on 2‐MCPD‐E. Water degumming was able to reduce the concentrations of 3‐MCPD‐E by 84% and Gly‐E by 26%. Neutralization of the oil reduced concentrations of 3‐MCPD‐E by 81% and Gly‐E by 84%. Bleaching with synthetic magnesium silicate reduced the 3‐MCPD‐E concentration by 67%. For the deodorization step, several mitigation strategies, such as double‐deodorization, the addition of various antioxidants, or a longer deodorization time, can reduce the formations of 3‐MCPD‐E by 82% and Gly‐E by 78%. Postrefining mitigation, including the use of absorbents, enzymes, or rebleaching of the oil, has also been reported to produce desirable contaminant reduction. Postrefining treatment with calcinated zeolite was able to reduce the 3‐MCPD‐E concentration by 19% and the Gly‐E concentration by 77%. Applying combined mitigation strategies to multiple steps of oil refining is likely crucial in order to adequately reduce levels of 3‐MCPD‐E and Gly‐E.     

基于植物油中脂肪酸烷基酯含量变化鉴别废弃油脂

采用固相萃取柱净化,气相色谱-质谱联用法测定了6种植物油中脂肪酸烷基酯(包括脂肪酸甲酯和脂肪酸乙酯)的含量,并研究其在植物油煎炸、废弃及废弃油脂精炼等环节中的变化。结果发现,6种植物油中脂肪酸烷基酯的含量均低于30 mg/kg,而植物油在废弃过程中可能会形成大量脂肪酸乙酯,生成量与油脂是否烹饪及废弃物中乙醇含量有关。脂肪酸烷基酯在脱色工艺中不能被去除,但在脱臭中可被去除。因此,可以通过测定植物油中脂肪酸烷基酯含量发现废弃油脂,为废弃油脂的鉴别工作提供新的思路。     

A gas chromatography-tandem quadrupole mass spectrometric analysis of policosanols in commercial vegetable oils

Reportedly policosanols (PCs) have various beneficial functionalities on health. A gas chromatography-tandem mass spectrometry (GC-MS/MS) with a low limit of detection (LOD), and high specificity, recovery, and precision was successfully established for the PC analysis in vegetable oils. The LODs for the PCs were in the range of 0.002 to 0.016 μg/mL. The relative standard deviation (RSD) for the repeated analysis of PCs was less than 3.356%. The mean recoveries for spiked heptacosanol and octacosanol in vegetable oil were 102.3% and 106.3%, respectively. The total PC contents in the vegetable oils varied from 3.01 to 427.83 mg/kg oil. Perilla seed, grape seed, and rice bran oils were found to be highly rich sources of PCs, containing 427.83, 245.15, and 171.17 mg PCs/kg oil, respectively. Corn, sesame, and soybean oils contained only a negligible quantity of PCs. The PC composition in vegetable oils was greatly source dependent. In perilla seed oil, octacosanol was the single most predominant component, representing 55.93% of the total PC. In grape seed oil, however, hexacosanol is the most abundant PC, followed by octacosanol, tetracosanol, and triacontanol in a decreasing order. The major PCs in rice bran oil were triacontanol, octacosanol, hexacosanol, and tetracosanol, which constituted over 87.3% of the total PC. This represents the 1st report on the composition and contents of PC in most vegetable oils analyzed here. PRACTICAL APPLICATION: The information might be used for the development of vegetable oil products with beneficial functionality.     

化学计量学与三酰甘油酯在食用油保真中的研究进展

食用植物油保真检测技术是食用植物油打假和保证人民身体健康的重要手段。三酰甘油酯是占食用植物油90%以上的主要成分,但是我国目前的检测技术仅能检测三酰甘油酯酰基链结构,即通过甲酯化方式检测脂肪酸含量,该方法不能真实反映三酰甘油酯的结构和含量。本文综述国内外最新的三酰甘油酯分析技术和化学计量学分析三酰甘油酯指纹谱的食用植物油保真检测技术研究进展,为保障我国食用植物油安全消费提供重要的技术支撑。     

植物油对被孢霉菌发酵生产花生四烯酸的影响

研究了四种植物油(豆油、棕榈油、花生油、芝麻油)对被孢霉菌发酵生产花生四烯酸(Arachidonic acid, AA)的影响.结果表明:(1)四种植物油显著促进了菌体油脂的积累;(2)被孢霉生长在以植物油为唯一碳源的培养基上时,菌体油脂中的AA含量比以葡萄糖为碳源时显著下降;生长在以植物油和葡萄糖为混合碳源的培养基上时,与以葡萄糖为碳源相比油脂中的AA含量仍然下降,但比生长在以植物油为唯一碳源时AA含量有所提高.说明这四种植物油对花生四烯酸的合成有抑制作用.(3)菌体油脂成分与培养基中植物油的油脂成分有一定的相似性.     

Production of set yoghurt analogue through replacement of milk fat with canola and sesame oil

The aim of this study was to determine the effect of fat level and composition on chemical, textural, microbial and sensory properties of set yoghurt analogue. The best fat level for production of yoghurt analogue was found to be 2% (w/v). Studies on the effect of fat composition (canola‐to‐sesame oil ratios of 2.0/0, 1.3/0.7, 0.7/1.3, 2.0/0) indicated the superior performance of pure sesame oil. Increasing the canola‐to‐sesame oil ratio generally resulted in an inferior product. Replacement of milk fat by vegetable oils yielded yoghurts with a lower saturated fatty acid content and less firmness.     

Determination of Tert‐Butylhydroquinone in Vegetable Oils Using Surface‐Enhanced Raman Spectroscopy

Monitoring the level of tert‐butylhydroquinone (TBHQ), a permissible antioxidant additive in edible vegetable oils in many countries, is important to ensure that oils and products that contain them comply with the relevant import regulations. Surface‐enhanced Raman spectroscopy (SERS) technology coupled with chemometric methods including partial least squares (PLS) and support vector machine (SVM) regression was applied to determine levels of TBHQ in spiked corn oils (0 to 500 mg/kg, n = 40) and commercial vegetable oils (0 to 99.7 mg/kg, n = 25). The lowest detectable concentration was 5 mg/L for TBHQ in standard solutions and 10 mg/kg of TBHQ in vegetable oils from various plant sources. The TBHQ levels predicted by the PLS or SVM model had a high correlation with actual TBHQ levels in commercial oil samples (SVM: R² = 0.972, ratio of performance to deviation [RPD] = 5.55, root mean square error [RMSE] = 5.73 mg/kg; PLS: R² = 0.976, RPD = 6.43, RMSE = 4.94 mg/kg), indicating great potential of SERS methods for detection and quantification of TBHQ in oils from a variety of sources.     

油脂加工减控反式脂肪酸技术研究进展

该文简介反式脂肪酸性质、来源、分类、对人体健康主要危害及世界各国管理规定,分析油脂加工过程中反式脂肪酸生成机理、途径及影响其生成工艺技术参数,重点综述阻断或减少油脂加工过程中反式脂肪酸生成途径与方法,并提出减控反式脂肪酸生成技术研究、反式脂肪酸安全风险分析与控制、监督管理措施等方面建议。     

基于气相离子迁移谱对葵花籽油精炼程度的检测

运用气相离子迁移谱（gas chromatography-ion mobility spectrometry,GC-IMS）对不同精炼程度的葵花籽油的挥发性有机成分进行分析,构建葵花籽油精炼程度的指纹图谱,并对葵花籽油的精炼程度进行判别和分类。采用二维差谱方法筛选出22?个有效特征峰作为表征精炼程度差异的变量,采用主成分分析和有监督模式识别方法（K最近邻、二次线性判别分析、Fisher线性判别分析）进行模式识别。结果表明,3?种有监督模式识别方法均可以有效地区分不同精炼程度的葵花籽油样,识别率高达97.30%。使用GC-IMS技术结合化学计量学方法能够准确直观地区分不同精炼程度的葵花籽油样品,便于企业对植物油进行质量控制,同时为质检技术人员提供了一种新的检测方法。     

食用油脂物理精炼和化学精炼诸多因素的比较

目前,在我国具有一定规模的禽用油脂精炼工厂（车间）中,以物理精炼或化学精炼的方法加工着不同品种的植物油脂,或以此两种不同的方法加工着同一品种的油脂。这两种方法的优缺点已成为多年来争议的焦点之一。列举了物理精炼和化学精炼中的许多因素,并加以对照、比较,以期对它们有更好的了解。     

食用植物油营养功能成分及检测技术的研究进展

食用植物油是人体生命活动和机体代谢过程中不可或缺的物质,不仅为人体提供能量、必需脂肪酸,还含有植物甾醇、维生素E、多酚、角鲨烯和类胡萝卜素等多种营养功能成分。研究表明,植物甾醇具有降低胆固醇水平、抗动脉粥样硬化和抗肿瘤等功能;维生素E可以抑制油脂过氧化,增加机体免疫能力,预防和治疗心血管疾病等;多酚具有消炎、预防冠心病等功能;角鲨烯具有促进血液循环、活化机体细胞等功能。本文主要对植物油中的营养成分及相应检测技术进行了简要综述,旨在促进植物油营养成分的深入研究,挖掘食用油潜在营养成分和价值,为指导消费者合理使用食用油提供科学依据。     

6种食用植物油及其生物柴油中脂肪酸成分的比较研究

采用毛细管气相色谱法，以氢火焰为检测器，测定了菜籽油、花生油、玉米油、棉籽油、芝麻油和大豆油及其相应生物柴油中脂肪酸的组成。比较发现，植物油及其生物柴油中脂肪酸组成基本一致。因此，可以通过测定植物油中脂肪酸的组成来预测生物柴油中脂肪酸甲酯的分布。     

植物油角鲨烯含量及其影响因素

植物油是一类经植物原料提取的富含多种微量营养成分的油脂。角鲨烯是植物油中营养伴随物之一,对人体生理健康?和疾病预防有着积极作用。通常,不同种类植物油中角鲨烯含量差距明显,甚至同种植物油中角鲨烯含量因地域、提取部位、加工工艺等因素而存在显著差异。因此,了解植物油角鲨烯含量并探究影响其角鲨烯含量的因素,可有效保存其角鲨烯成分,提升植物油营养品质和健康价值。本文介绍了多种植物油角鲨烯含量,并分析比较了植物油种类,原料品种、成熟度、产地、提取部位及油脂提取工艺、精炼工艺、储藏条件对其角鲨烯含量的影响,以期为优化植物油选择及改进加工工艺提供参考,并且为进一步提升植物油营养品质和健康价值提供理论基础。     

电子舌快速检测食用植物油掺伪

目的应用法国Alpha M.O.S公司生产的传感器型味觉电子舌系统对3组不同程度掺伪的食用植物油进行掺伪检测。方法选取6种不同类型植物油,用20%的乙醇浸泡后超声,静置隔夜,将油脂中的味觉信息提取出来,由电子舌自动进样系统采集原始数据,所得样品数据用主成分分析法、判别因子法进行分析。结果 2种方法均能较好地检测区分不同的食用植物油样品,大部分的指纹分辨指数高于95分。此方法可以区分不同榨取工艺或不同产地的同种类油脂,可鉴别的掺伪检测限为0.1%。结论本实验鉴别精确度远大于常规的油脂检测方法,且具有较高的灵敏度,能够快速有效地鉴别不同种类食用植物油并区分不同掺杂比例的油脂样品。     

燕麦油理化性质及成分分析

采用溶剂浸提法提取燕麦油,并将其精制。测定燕麦粗油VE和磷脂的含量,以及精制前后燕麦油的理化性质及脂肪酸组成,探讨精制对燕麦油理化性质及成分的影响。结果表明：燕麦粗油中VE含量为 142.8mg/kg,磷脂含量为14.159mg/g。燕麦油具有燕麦香味,折射率n20约为1.47,比重约为0.92,碘值约为100g I2/100g,皂化值接近190mg KOH/g,不皂化物含量约为1%。精制后的燕麦油品质得到改善,各项指标均达到了食用植物油的质量要求。精制后,不饱和脂肪酸的含量增加了1.96%。燕麦油可作为一种富含不饱和脂肪酸的功能性植物油。     

气相色谱-离子迁移谱分析不同植物油 浸提的花椒油的挥发性成分

通过了解不同植物油浸提的花椒油的挥发性成分(VOCs)特征,获得筛选花椒浸提用植物油的方法。利用气相色谱(GC)和离子迁移谱(IMS)联用技术对不同植物油浸提的花椒油的VOCs进行采集和分析。结果表明:不同植物油浸提的花椒油的VOCs差异较大。GC-IMS可有效分离各花椒油中极性相近的VOCs,并筛选出50种离子峰强度变化明显的VOCs;通过二维数据可视化方式可显示各VOCs离子峰的差异;经数据降维处理后构建主成分分析模型,可将不同植物油浸提的花椒油根据浸提用植物油的不同进行聚类。相似度分析表明,与一级压榨菜籽花椒油相似度最高的是一级浸出菜籽花椒油,其次为大豆花椒油。因此,利用GC-IMS技术获取不同植物油浸提的花椒油产生的VOCs组成特征来筛选花椒油生产企业用的植物油原料的方法是可行的。