非烃类物质作为食用植物油浸出溶剂的安全性分析

工业正己烷作为主要的食用油浸出溶剂已经使用多年,但正己烷有害于人体健康和环境安全,且易引起爆炸与灾害,影响作业安全性。因此,选择更适宜的浸出溶剂为各国油脂工作者所重视。介绍了有望替代己烷等烃类作为食用油浸出溶剂的几种非烃类物质的物化特性,特别是它们的毒性,以供业界参考。     

四号溶剂浸出油脂工艺的生产安全和食品安全

对用于食用油脂浸出的四号溶剂的性质、浸出工艺、生产安全及食品安全进行了讨论。四号溶剂主要成分为液化丁烷。与六号溶剂浸出油脂相比,四号溶剂浸出具有能耗低,残溶小,溶剂毒性小等特点。四号溶剂的罐组式浸出工艺已经成熟,并已经用于实际生产中。国际组织和发达国家都普遍认可了丁烷、丙烷在食品中应用的安全性,但都没有制定其作为食品助剂的质量标准,我国应尽快制定丁烷、丙烷食品助剂标准。     

蒸脱粕残留溶剂测试研究

在油脂浸出厂中,需要测定蒸脱粕中残留溶剂量.本文根据浸出油时所用溶剂组成分析结果,又通过气相色谱分析相关成分的谱图,论证了在色谱图中蒸脱粕中残留溶剂所对应的流出峰（保留时间）,从而确证了蒸脱粕中溶剂残留量,为指导生产提供了理论根据。     

浸出制油技术研究进展

与压榨法制油技术相比,浸出制油法技术具有诸多优点,但现行油脂工业浸出制油技术的应用因健康及环保问题受到人们的不断质疑.为此,各国油脂科技工作者对新型浸出制油技术的新型替代溶剂筛选及其应用展开了大量的研究工作.其中,以饱和烃类溶剂、低碳链醇类溶剂、超临界二氧化碳及酶法浸出技术为目前的研究热点.就以上浸出技术的最新进展进行综述,重点介绍其工艺、装备及安全、环保等,以供业界参考.     

食用植物油中残留溶剂的高温顶空气相色谱分离与测定

对食用油中C5～C8烃类残留溶剂的高温顶空气相色谱分离与测定进行方法学考察。样品在90℃进行顶空平衡以提高样品残留溶剂组分在顶空气相中的分配,并采用25%角鲨烷填充色谱柱对溶剂组分进行分离和定量分析。结果表明,30min内的高温平衡对组分测定无干扰;不同组分保留时间的RSD均不超过0.2%、峰面积的RSD也均小于5%,方法的回收率为99.2%,最低定量限均低于0.5mg/kg;顶空分析的相平衡条件、色谱分离模式不同导致本方法与国家标准方法的测定结果间存在显著差异;国家标准方法中六号溶剂标准溶液的配制对定量分析结果影响显著。本方法可用于监控油脂加工中溶剂残留的变化以及精炼油的质量检测。     

甲基戊烷四级逆流浸出膨化大豆料

分别以正己烷、甲基戊烷为浸出溶剂,采用四级逆流浸出方式从浸出效果、浸出油品两个方面评价了两种浸出溶剂对浸出膨化大豆料的影响。浸出效果方面,考察了浸出混合油质量分数、浸出湿粕静吸附率、浸出干粕残油率;浸出油品方面,考察了浸出毛油脂肪酸组成、酸值、色泽、微量组分以及残留溶剂,并与正己烷进行比较。结果表明:甲基戊烷各级浸出混合油质量分数相对较高,提油率高;甲基戊烷浸出湿粕静吸附率、浸出干粕残油率分别为(19.00±0.45)%和(0.57±0.08)%,正己烷浸出湿粕静吸附率、浸出干粕残油率分别为(20.65±0.20)%和(0.71±0.01)%;两种溶剂浸出毛油脂肪酸组成无差异,甲基戊烷浸出毛油酸值、总含磷量、残留溶剂含量、生育酚含量、甾醇含量均较低,而角鲨烯含量较高,具有精炼损失少、节能优势。研究表明新型溶剂甲基戊烷是替代正己烷作为浸出溶剂的良好选择。     

作为植物油浸出溶剂烃类毒性

该文主要介绍己烷、环己烷、环戊烷、庚烷、戊烷等烃类的物化特性及其作为浸出溶剂安全性,为新型植物油浸出溶剂筛选提供依据和参考。     

气相色谱法测定浸出可可脂四号溶剂残留

对用四号溶剂浸出提取的可可脂中残留溶剂的测定提供了气相色谱分析方法.介绍了标准气体制作、色谱测定条件选择、标准曲线制作与定量等测定关键点及注意方面.     

食用油中残留溶剂组成对溶剂残留量测定的影响

应用气相色谱仪结合气相色谱质谱联用仪分析测定大豆原油中残留6号溶剂的组成及各组分的面积百分含量,揭示6号溶剂在各批次的大豆原油中各组成比例差异显著。以新鲜机榨大豆油作基质配制各组分的标准混合溶液,分析计算各组分的相对质量校正因子在0.34~0.81之间,用配对t检验法验证采用各组分标准溶液,以外标法分别定量后加和计算的方法可实现对不同批次样品中溶剂残留量的准确测定。     

降低浸出车间溶剂损耗之我见

<正> 对于一个浸出车间来说,降低溶剂损耗的重要性,这是大家都很清楚的。如何降低溶剂的损耗,这是浸出设备设计、制造单位和使用单位共同关心的问题。浸出车间溶剂损耗主要由五个方面组成:1.从进料口逸出溶剂;2.浸出毛油中带走溶剂;3.粕中带走溶剂;4.排出尾气中带走溶剂;5.设备的跑冒滴漏带走溶剂。要降低溶剂损耗;必须解决这五个方面的问题笔者仅就这五个方面谈一点敷浅认识。一、如何控制从进料口逸出溶剂从原料进入浸出车间到浸出器之间,一般工厂都是采用封闭绞龙(或封闭阀)加上存料箱来封住溶剂汽体的逸出。事实上,单靠     

食用油脂中挥发性卤代烃的HS-SPME-GC联用分析

目的：建立进出口油脂中挥发性卤代烃(VHHs)的顶空-固相微萃取-气相色谱(HS-SPME-GC)联用分析方法。方法：采用Supelco公司5种SPME纤维头对食用油脂进行顶空萃取,比较不同萃取纤维的萃取效率,分别考察萃取温度、时间、顶空体积等对萃取效果的影响。用毛细管色谱柱分离萃取成分、气相色谱-电子捕获检测器(GC-ECD)进行检测。结果：优选的SPME纤维头为75μm碳分子筛-聚二甲基硅氧烷(CAR/PDMS)。于15mL顶空萃取瓶中加入9mL食用油,在60℃恒温水浴中萃取30min后,290℃解吸3min进行GC分析。方法检测限为0.02～1.4ng/mL,回收率在89%～105%之间,相对标准偏差(RSD)小于8.5%(n=5)。结论：该方法具有操作简便、快捷、灵敏度高、检测限低、不使用有机溶剂等特点,适合于食用油脂中挥发性卤代烃的检测。     

固相萃取柱净化-气相色谱法定量测定食用植物油中饱和烃类矿物油

目的以自制硫酸硅胶和10%硝酸银硅胶填料分层装填的复合固相萃取柱为净化手段,建立一种测定食用植物油中饱和烃类矿物油的分析方法。方法样品经正己烷提取,固相萃取柱净化,氮吹浓缩,然后经DB-1石英毛细管色谱柱分离,采用气相色谱-火焰离子化检测器检测,外标法定量。结果考察了填料类型、填料用量、洗脱体积等因素对提取效率的影响。在优化的条件下,饱和烃类矿物油检测的线性范围为5.0~500.0mg/L,相关系数r~2=0.9991,方法检出限为3.0 mg/kg,定量限为10.0 mg/kg。样品在10.0、20.0、50.0 mg/kg 3个水平下的加标回收率为93.2%~103.7%,相对标准偏差为3.97%~5.33%(n=6)。结论该法操作简单、快速、准确度高,检出限能满足对食用植物油中饱和烃类矿物油残留的检测要求,且使用常规分析仪器、分析成本低,值得推广应用。     

Headspace solid-phase microextraction as a tool to estimate the contamination of smoked cheeses by polycyclic aromatic hydrocarbons

Headspace solid-phase microextraction (HS-SPME) was used to study polycyclic aromatic hydrocarbons (PAH) in smoked cheeses. Two types of fiber coatings and different extraction conditions were tested. The results reveal that the use of an 85-microm polyacrylate fiber immersed in the headspace of the samples at 70 degrees C for 60 min is suitable for the detection of PAH with no more than 4 aromatic rings. To determine if a relationship can be established between the results obtained using a solvent extraction technique and HS-SPME, 6 samples of smoked cheese previously studied by a solvent extraction method were analyzed by HS-SPME, and the results obtained by both methodologies were compared. Polycyclic aromatic hydrocarbons were identified and quantified by gas chromatography-mass spectrometry operating in selective ion monitoring mode. Among the PAH determined by the solvent extraction method, only those with 4 aromatic rings or less were detected by HS-SPME and, consequently, this technique does not allow one to determine the PAH content of smoked cheese samples under the conditions of the study. Nevertheless, the relationship between the results obtained by both techniques for some PAH revealed that HS-SPME could be useful as a screening method to distinguish among samples with different degrees of PAH contamination.     

同时蒸馏萃取法提取花椒挥发油的工艺优化

分别对同时蒸馏萃取法提取花椒挥发油的影响因素、溶剂种类、原料粉碎粒度、提取时间、辅助方式进行了单因素实验。结果表明:优化的提取工艺为,选择选择乙醚作为最佳提取溶剂,花椒挥发油提取率达到了8.2%左右,所得色谱峰信息较多而且溶剂毒性较小;原料最佳粉碎粒度为40目,其挥发油的提取率达到了9.4%;最佳提取时间为3 h时,青花椒挥发油的提取率接近9.5%;超声波5 min作为最佳辅助处理方式,青花椒挥发油提取率接近12%,而且色谱峰所显示的信息较多。     

Extraction of Cuminum cyminum essential oil by combination technology of organic solvent with low boiling point and steam distillation

Extraction of essential oil from Cuminum cyminum seeds using a combination of organic solvent with low boiling point and steam distillation was explored. The effect of different parameters, such as particle size (40, 60, 80 mesh), temperature (°C) 10, 15, 20 and extraction time (3, 5, 8 h), on the extraction yield was investigated using three-level orthogonal array design. The experimental results showed that the temperature had the largest effect on the yield of the extract (oleoresin), followed by extraction time and particle size. The optimum parameters, such as temperature, particle size, and extraction time were in turn 20 °C, 80 mesh, and 8 h. Essential oil of C. cyminum seeds obtained by supercritical fluid extraction (SFE), hydrodistillation (HD), combination technology of organic solvent with low boiling point and steam distillation (OS-SD) were further analysed by gas chromatographic/mass spectrometric detection to compare the extraction methods. Forty-five compounds in the C. cyminum essential oil were identified, showing that the composition of the extraction by different methods was mostly similar, whereas relative concentration of the identified compounds was apparently different. General characteristics of the C. cyminum essential oil obtained by different methods were further compared, and OS-SD was considered as the optimum process among the three processes to obtain C. cyminum essential oil for high quality, simple technology and low cost.     

Pressurized solvent extraction of wheat germ oil

This study examined the pressurized solvent extraction of wheat germ oil. The effects of temperature (45–135 °C at 1500 psi), extraction time, sample size and solvent type on the extraction efficiency and oil quality were studied. Extraction efficiency of the normal-hexane was compared to that of the iso- and high purity-hexane, iso-propanol, ethanol and acetone. The extracts were analyzed for n-3 and n-6 polyunsaturated fatty acid content. Pressurized solvent extraction reduced extraction time significantly as compared to Soxhlet extraction. The time required for complete oil recovery was dependent on the amount of wheat germ used for extraction. The amount of extract collected was highest when ethanol was used as a solvent for pressurized solvent extraction. Soxhlet and pressurized solvent extractions resulted in similar oil yields when hexane was used as a solvent. Fatty acid composition of the extracts was not affected by either temperature or extraction method. The experimental results indicate that a pressurized solvent extraction technique reduces solvent consumption and extraction time with no adverse effect on the extraction yield and fatty acid composition of the oil.     

Saturated hydrocarbon content in olive fruits and crude olive pomace oils

Olive fruits contain an n-alkane series of saturated hydrocarbons mainly in the pulp. Lower amounts of a complex mixture of paraffins, unresolved by gas chromatography (UCM – unresolved complex mixture), have been found in cuticle, stone (woody shell and seed), olive leaves, and talc used as an aid to olive oil extraction. The amounts of both kinds of hydrocarbons are related to the olive cultivar and are transferred to oils in a proportion depending on the oil-obtaining process (centrifugation or solvent extraction). In olive oil obtained by centrifugation, only n-alkanes were detected. However, in olive oil extracted by second centrifugation, small amounts of UCM paraffins were detected together with the n-alkanes. Olive pomace oils showed a very variable content of both types of hydrocarbons according to the different obtaining process, such as double centrifugation, solvent extraction or centrifugation followed by solvent extraction. ‘White mineral oil’ used in oil extraction machinery is the source of the high concentrations of UCM paraffins found in some olive and olive pomace oils. In the case of second centrifugation olive oil, a maximum limit of 50 mg kg^?1 of UCM is suggested, whereas in the case of crude olive pomace oil, it amounts to 250 mg kg^?1 plus an additional minimum of 1.0 for the n-alkanes/UCM ratio.     

Microbial communities involved in methane production from hydrocarbons in oil sands tailings

Microbial metabolism of residual hydrocarbons, primarily short-chain n-alkanes and certain monoaromatic hydrocarbons, in oil sands tailings ponds produces large volumes of CH(4) in situ. We characterized the microbial communities involved in methanogenic biodegradation of whole naphtha (a bitumen extraction solvent) and its short-chain n-alkane (C(6)-C(10)) and BTEX (benzene, toluene, ethylbenzene, and xylenes) components using primary enrichment cultures derived from oil sands tailings. Clone libraries of bacterial 16S rRNA genes amplified from these enrichments showed increased proportions of two orders of Bacteria: Clostridiales and Syntrophobacterales, with Desulfotomaculum and Syntrophus/Smithella as the closest named relatives, respectively. In parallel archaeal clone libraries, sequences affiliated with cultivated acetoclastic methanogens (Methanosaetaceae) were enriched in cultures amended with n-alkanes, whereas hydrogenotrophic methanogens (Methanomicrobiales) were enriched with BTEX. Naphtha-amended cultures harbored a blend of these two archaeal communities. The results imply syntrophic oxidation of hydrocarbons in oil sands tailings, with the activities of different carbon flow pathways to CH(4) being influenced by the primary hydrocarbon substrate. These results have implications for predicting greenhouse gas emissions from oil sands tailings repositories.     

Gas Chromatographic Determination of Butylated Hydroxyanisole, Butylated Hydroxytoluene and Tertiarybutyl Hydroquinone in Soybean Oil

Oils containing different levels of the most common phenolic antioxidants, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and tertiarybutyl hydroquinone (TBHQ) from 0–200 ppm were analyzed by a new gas chromatographic method. The antioxidants in oils were isolated by nitrogen gas purging, collected on Tenax GC coated with polymetaphenoxylene, and then separated and quantitated by gas chromatography. This method requires neither extraction of antioxidants from oil nor derivatization of antioxidants. The correlation coefficients (r) between gas chromatographic peak heights or peak area and their concentrations in oils were 0.99 for BHA, BHT, and TBHQ. This simple gas chromatographic method can determine as little as 10 ppm pf BHA, BHT, or TBHQ in oils in an hour.     

Saturated and aromatic mineral oil hydrocarbons from paperboard food packaging: estimation of long-term migration from contents in the paperboard and data on boxes from the market

In the absence of a functional barrier, mineral oil hydrocarbons from printing inks and recycled fibres tend to migrate from paper-based food-packaging materials through the gas phase into dry food. Concentrations easily far exceed the limit derived from the acceptable daily intake (ADI) of the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Since the estimation of long-term migration into the food by testing at 40°C for 10 days is difficult, it seems preferable (and easier) to use the mineral oil content in the paperboard. Evaporation experiments showed that hydrocarbons eluted up to about n-C?? are sufficiently volatile for relevant migration into dry food: in worst-case situations, about 80% migrate into the packed food. The extraction of the paperboard was optimised to give good recovery of the relevant hydrocarbons, but to discriminate against those of high molecular mass which tend to disturb gas chromatographic analysis in on-line coupled normal phase HPLC-GC-FID. Even though some of the relevant hydrocarbons had already evaporated, the average concentration of < C?? mineral oil saturated hydrocarbons (MOSH) in the paperboard boxes of 102 products from the Swiss and Italian market was 626 mg kg?1. Nearly 15% of investigated boxes still contained more than 1000 mg kg?1 < C?? MOSH up to over 3000 mg kg?1 (maximum = 3500 mg kg?1). This amount of MOSH in the board have the potential of contaminating the packed food at a level exceeding the limit, derived from the JECFA ADI, hundreds of times.