气相色谱-质谱联用法测定液体调味料中4种氯丙醇的含量

选取酱油、鱼露与水解植物蛋白液为试验样品,建立了液体调味料中3-氯-1,2-丙二醇（3-MCPD）、2-氯-1,3-丙二醇（2-MCPD）、1,3-二氯-2-丙醇（1,3-DCP）和2,3-二氯-1-丙醇（2,3-DCP）的气相色谱-质谱联用（GC-MS）检测方法。以样品加入稳定同位素内标后进行固相支持液液萃取,以10 m L正己烷淋洗,15 m L乙酸乙酯洗脱,氮吹近干后,七氟丁酰基咪唑衍生,产物经DB-5MS柱分离,质谱采用选择离子监测模式检测。结果表明,四种氯丙醇在0.005～1.6μg/m L质量浓度范围内呈良好线性关系,3-MCPD、2-MCPD、1,3-DCP和2,3-DCP的检出限分别为2.0μg/kg、2.0μg/kg、5.0μg/kg、5.0μg/kg,定量限分别为5.0μg/kg、5.0μg/kg、10μg/kg、10μg/kg,加标回收率在82.4%～107.0%范围内,精密度实验结果的相对标准偏差（RSD）在0.85%～8.58%范围内。该方法前处理简便,定量准确可靠,可用于液体调味料中四种氯丙醇含量的检测。     

气-质联用测定食品接触用纸制品中氯丙醇的迁移量

建立了气相色谱-质谱联用法(GC-MS)同时检测食品接触用纸制品中1,3-二氯-2-丙醇(1,3-DCP)、2,3-二氯-1-丙醇(2,3-DCP)、2-氯-1,3-丙二醇(2-MCPD)与3-氯-1,2-丙二醇(3-MCPD)四种氯丙醇迁移量的测定方法,食品模拟物包括4%乙酸、10%乙醇,50%乙醇与橄榄油。通过方法优化,四种氯丙醇的方法检出限与定量限分别为2μg/kg与10μg/kg,加标回收率为87.3%～109%,相对标准偏差(RSD)为1.1%～9.5%(n=6)。实验表明,该方法准确度高,重现性好,可满足纸制品中氯丙醇迁移量的检测要求。应用此方法对15批次纸制品进行检测,结果显示,3-MCPD迁移量的检出率与检出水平最高,1,3-DCP与3-MCPD迁移量的检出率分别为33.3%与53.3%,迁移量分别为2.27～12.04μg/kg与2.51～183.32μg/kg,2,3-DCP与2-MCPD迁移量均为未检出;氯丙醇在水基模拟物的迁移水平比橄榄油模拟物的迁移水平高。纸制品中普遍检出1,3-DCP与3-MCPD迁移,其对食品安全的影响需引起关注。     

氯丙醇检测方法研究进展

氯丙醇类化合物是国际公认的食品污染物,包括3-氯-1,2-丙二醇(3-MCPD)、2-氯-1,3-丙二醇(2-MCPD)以及双氯取代的1,3-二氯-2-丙醇(1,3-DCP)和2,3-二氯-1-丙醇(2,3-DCP)。文章综述了国内外氯丙醇检测方法的研究进展,包括气相色谱(GC)法、气质联用(GC/MS)法、气相色谱双串联质谱(GC/MS/MS)联用法以及其它新的检测方法。     

酱油中双氯丙醇的顶空固相微萃取-气相色谱-质谱法测定

目的建立酱油中双氯丙醇(1,3-dichloro-2-propanol即1,3-DCP和2,3-dichloro-1-propanol即2,3-DCP)的顶空固相微萃取-气相色谱-质谱法的测定方法。方法采用涂层膜厚为75μm的CarboxenTM/聚二甲基硅氧烷(CAR/PDMS)的固相微萃取纤维,在50℃水浴中对酱油样品直接进行萃取30min后移至气相色谱质谱联用仪上,经DB-WAX毛细管柱(30m×0.25mm×0.25μm)分离后质谱测定,以d5-1,3-DCP为内标进行内标法定量。结果酱油样品中1,3-DCP及2,3-DCP的含量与1,3-DCP及2,3-DCP和d5-1,3-DCP内标的峰面积比呈良好的线性关系,线性范围为5～160μg/kg,相关系数大于0.998。以空白酱油为基质做了3个添加水平(5、20和50μg/kg)的加标回收实验,回收率在82.3%～113.4%之间,相对标准偏差(RSD,n=7)在2.5%～10.6%之间,方法的精密度和准确度良好。酱油中1,3-DCP和2,3-DCP的检测限分别为2和0.5μg/kg。对酱油样品进行了测定,结果满意。结论该方法简单、快速、准确、灵敏度高、无需使用有机溶剂,适用于酱油样品中双氯丙醇的直接测定。     

基于稳定同位素稀释法测定调味品中氯丙醇的含量

基于气相色谱-质谱法(Gas chromatography-mass,GC-MS),探究和建立了调味品中3-氯-1,2-丙二醇(3-MCPD)、2-氯-1,3-丙二醇(2-MCPD)、1,3-二氯-2-丙醇(1,3-DCP)、2,3-二氯-1-丙醇(2,3-DCP)的分析方法。优化了样品前处理方法及GC-MS的分析条件。结果显示,样品经硅藻土固相萃取柱净化,乙醚洗脱,七氟丁酰基咪唑衍生化后,在GC-MS选择离子模式(SIM)下测定,氯丙醇在(0.005~2)mg/L范围内呈良好线性,相关系数均大于0.99,检出限(S/N=3)为2μg/kg,定量限(LOQ)为5μg/kg,加标回收率为80.1%~109.5%。该方法简便、快速、溶剂用量少、且能消除调味品中复杂基质的干扰,结果准确可靠、灵敏度高,适用于调味品中氯丙醇的同时测定。     

我国市售酱油氯丙醇污染研究:地区间污染水平的比较

采用稳定性同位素稀释气相质谱法定量测定多组分氯丙醇,调查了我国市售酱油氯丙醇的污染水平。调查分3次进行,所抽查的629份市售酱油产于2003~2004年间,来自我国11个省、市。各地区样品3-氯-1,2-丙二醇(3-MCPD)的检出率均较高,在90%~100%之间,3-MCPD水平在0.003~189 mg/kg之间,几何均数为21.1μg/kg;2-氯-1,3-丙二醇(2-MCPD)的检出率在14.3%~83.8%之间;1,3-二氯-2-丙醇(1,3-DCP)、2,3-二氯-1-丙醇(2,3-DCP)的检出率分别在0%~24%、0~18.9%之间,全部样品的几何均数低于定量限。总体上,我国市售酱油氯丙醇污染水平有明显下降,但以各地有限的抽查样品评价,污染的地区差异明显,来自河南、广西、浙江样品污染水平以及检出率相对较高,而福建、江苏、北京以及上海样品污染水平较低。     

部分省份食用植物油中脂肪酸氯丙醇酯含量水平调查分析

研究调查了10个植物油品种的491批次食用植物油样本中3-氯-1,2-丙二醇脂肪酸酯(3-MCPD酯)、2-氯-1,3-丙二醇脂肪酸酯(2-MCPD酯)、1,3-二氯-2-丙醇脂肪酸酯(1,3-DCP酯)和2,3-二氯-1-丙醇脂肪酸酯(2,3-DCP酯)4种脂肪酸氯丙醇酯的含量水平,为监管工作提供基础数据。用间接测定法以七氟丁酰基咪唑(HFBI)为衍生剂,GC-MS测定,多同位素内标法定量。调查结果显示:所有样本均未检出1,3-DCP酯和2,3-DCP酯;3-MCPD酯检出率为83.3%,检出结果范围为0.104~8.580 mg/kg;2-MCPD酯检出率为66.0%,检出结果范围为0.106~4.320 mg/kg;3-MCPD酯和2-MCPD酯的同时检出率为65.2%;脂肪酸氯丙醇酯含量水平较高的油脂品种是棕榈油和油茶籽油,含量水平较低的油脂品种是橄榄油和大豆油;不同植物油品种脂肪酸氯丙醇酯含量水平差异较大。     

微乳毛细管电动色谱法检测鸡精中的3种氯丙醇

建立了微乳毛细管电动色谱分离检测3种氯丙醇的方法。考察了表面活性剂十二烷基硫酸钠(SDS)浓度、缓冲液pH及浓度、有机添加剂、助表面活性剂浓度、温度和运行电压对3-氯-1,2-丙二醇(3-MCPD)、1,3-二氯-2-丙醇(1,3-DCP)和2,3-二氯-1-丙醇(2,3-DCP)分离的影响。结果表明,最佳的微乳液组成为:3.31%(w/v)SDS,6.61%(w/v)正丁醇,0.81%(w/v)正辛烷,10%(v/v)乙腈,79.3%(v/v)5 mmol/L磷酸盐-硼砂缓冲液(pH9.0)。该微乳体系中有机溶剂乙腈对氯丙醇的分离起到了重要作用。当分离电压为20 kV、分离温度为20℃、检测波长192 nm时,3种氯丙醇在16 min内达到基线分离。3-MCPD的线性范围为2.5～500μg/mL,1,3-DCP和2,3-DCP的线性范围均为1.0～500μg/mL,相关系数均大于0.998,检出限(S/N=3)分别为0.5、0.4、0.5μg/mL。该法操作简单,灵敏度高,实验结果准确可靠,用于鸡精样品中3种氯丙醇的同时检测,结果满意。     

食用植物油中4种氯丙醇脂肪酸酯的GC-MS测定方法研究

采用气相色谱-质谱(GC-MS)联用技术,建立了同时测定食用植物油中3-氯-1,2-丙二醇脂肪酸酯(3-MCPD酯)、2-氯-1,3-丙二醇脂肪酸酯(2-MCPD酯)、1,3-二氯-2-丙二醇脂肪酸酯(1,3-DCP酯)和2,3-二氯-1-丙二醇脂肪酸酯(2,3-DCP酯)含量的分析方法。该方法在0.005~0.5 mg/L范围内线性关系良好,检出限0.1 mg/kg,定量限0.2 mg/kg,加标回收率在97.2%~106.0%之间,相对标准偏差在3.4%~7.1%之间。该方法操作简便,灵敏度高,重复性好,定性定量准确,对仪器污染小,能满足食用植物油中氯丙醇酯的检测需求。     

稳定性同位素稀释技术结合GC-MS测定酱油中多组分氯丙醇的研究

目的　以两种同位素内标建立同时测定酱油中 4种氯丙醇的GC -MS方法。方法　试样中加入稳定性氘代同位素内标 ,采用硅藻土Extrelut NT进行基质固相分散萃取结合固相萃取净化酱油试样 ,经七氟丁酰衍生化后 ,在DB - 5毛细管柱中经程序升温得到良好的分离 ,用选择离子储存 (SIS)定量。结果　各个氯丙醇在进样量为 2 0～ 5 0 0pg范围内线性良好 (r >0 999) ,3-氯 - 1,2-丙二醇 (3-MCPD)、1,3-二氯丙醇 (1,3-DCP)和 2 ,3-二氯丙醇 (2 ,3-DCP)的定量限分别为0 0 0 3、0 0 0 5和 0 0 0 5mg kg ;3种浓度水平下加标重复测定 6次 ,回收率分别为 98 8%～ 115 %、75 0 %～ 119%和 93 6 %～ 132 % ,精密度分别为 6 99%～ 16 2 %、3 80 %～ 9 2 5 %和 7 0 7%～10 4 %。结论　该方法具有较高的灵敏度、准确度、精密度和特异性 ,满足了酱油样品中痕量氯丙醇的分析要求。     

Occurrence of chloropropanols in soy sauce and other foods in China between 2002 and 2004.

A survey of chloropropanols in soy sauce and some selected foods in China is reported. Thirty-seven traditionally brewed soy sauce samples contained 3-MCPD below the EC maximum limit (ML) of 0.02 mg kg(-1). All soy sauce samples (629) from retailers contained levels of 3-MCPD ranging between <0.005 (LOQ) and 189 mg kg(-1), and only 12.2% had levels in excess of the Chinese ML of 1.0 mg kg(-1) for acid hydrolyzed vegetable protein (acid HVP). This indicates that the necessary processing changes have been made to decrease levels of chloropropanols in soy sauce. 2-Monochloropropane-1,3-diol (2-MCPD), 1,3-dichloro-2-propanol (1,3-DCP) and 2,3-dichloro-1-propanol (2,3-DCP) were detected in 48.1 19.1 and 3.78% of the soy sauce samples, respectively; the highest levels being 20.3, 8.26 and 0.50 mg kg(-1), respectively. A good linear correlation was found between the amount of 3-MCPD and 2-MCPD, with the level of 3-MCPD being generally higher than that of other chloropropanols for the same soy sauce. Acid HVP contained 3-MCPD at a level of 0.010-117.7 mg kg(-1) (on a liquid basis) and 80% of samples contained levels exceeding 1.0 mg kg(-1). In some other foods investigated, relatively high levels of 3-MCPD were found in soy sauce powder, oyster sauce, beef products, instant noodle spices and health foods, ranging from 0.029 to 13.64 mg kg(-1). It is concluded that abnormal levels of 3-MCPD in soy sauce or other foods produced in China may result from acid hydrolysis or the addition of the contaminated acid HVP.     

The simultaneous separation and determination of chloropropanols in soy sauce and other flavoring with gas chromatography-mass spectrometry in negative chemical and electron impact ionization modes

Both gas chromatography-mass spectrometry in electron ionization (GC-MS-EI) and negative chemical ionization (GC-MS-NCI) modes are reported in this paper for the simultaneous determination of 1,3-dichloropropan-2-ol (1,3-DCP), 2,3-dichloropropan-1-ol (2,3-DCP), 3-chloropropane-1,2-diol (3-MCPD) and 2-chloropropane-1,3-diol (2-MCPD) in soy sauce and other flavoring. D₅-3-MCPD (for 3-MCPD and 2-MCPD) and d₅-1,3-DCP (for 1,3-DCP and 2,3-DCP) were used as the deuterium isotopic labelled internal standards. The feasibility of using heptafluorobutyric anhydride modified with triethylamine (HFBA-Et₃N) as a new derivatization reagent to replace heptafluorobutyrylimidazole (HFBI) is proposed. Liquid/liquid extraction with hexane was introduced for high lipid content samples. A small survey was carried out of soy sauces (103 samples) and instant noodles (45 samples) and the applicability of GC-MS-NCI and GC-MS-EI was assessed in these different matrices.     

Study of chloropropanols in soy sauce by gas chromatography-triple quadrupole mass spectrometry with coupled column separation without derivatisation

A qualitative and quantitative determination method for chloropropanols in soy sauce was developed by GC-MS/MS with coupled column separation without derivatisation. The target compounds were 1,3-dichloropropan-2-ol (1,3-DCP), 2,3-dichloropropan-1-ol (2,3-DCP), 3-monochloropropane-1,2-diol (3-MCPD) and 2-monochloropropane-1,3-diol (2-MCPD). 3-MCPD-d₅ was used as an isotope internal standard for MCPDs and 1,3-DCP-d₅ for DCPs. After spiking with internal standards and mixed with 1?g of Extrelut? NT, about 1?g of the sample was washed by 4?ml of hexane and the analytes were eluted with 15?ml of 95% (v/v) ethyl ether/hexane mixture. The concentrated extract was directly injected without derivatisation, separated by a coupled column – a 3?m Innowax (polyethylene glycol) combined with a 30?m DB-5?ms ((5%-phenyl)-methylpolysiloxane) by a quartz capillary column connector – and detected by GC-MS/MS. The limits of detection (LODs) in the sample matrix were 1.0, 2.5, 5.0 and 5.0?µg?kg^?1 for the above chloropropanols, respectively. The relative proportions of 2-MCPD/3-MCPD ranged from 0.19 to 3.74 in soy sauce samples. 2,3-DCP and 2-MCPD were more stable than 1,3-DCP and 3-MCPD under alkaline condition. The levels of chloropropanols can be decreased by an alkaline treatment process.     

Survey of chloropropanols in soy sauces and related products

A survey of soy sauces and related products available in the USA was conducted to determine the levels of 3-monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) in these products. Fifty-five retail samples were purchased and analysed for 3-MCPD. 3-MCPD determinations were made according to a gas chromatography/mass spectrometry method validated by a collaborative trial. Eighty-five per cent of the samples analysed contained greater than the detection limit of 0.005 ppm (μg g^-1) for 3-MCPD. Thirty-three per cent contained greater than 1 ppm; the highest level was 876 ppm 3-MCPD. Thirty-nine of the samples analysed for 3-MCPD also were analysed for 1,3-DCP by using a modified method developed and validated in-house. Fifty-six per cent of the samples analysed for 1,3-DCP contained greater than the detection limit of 0.055 ppb (ng g^-1) for 1,3-DCP; the highest level was 9.8 ppm 1,3-DCP. Products manufactured in Asia contained the highest chloropropanol levels.     

Extracts from Erythronium japonicum and Corylopsis coreana Uyeki reduce 1,3-dichloro-2-propanol-mediated oxidative stress in human hepatic cells

Food Science and Biotechnology - In this study, it was demonstrated that 1,3-dichloro-2-propanol (1,3-DCP) induced oxidative stress and cell death in HuH7, human hepatocytes. The protective effects...     

Enrichment and characterization of chlorinated organophosphate ester-degrading mixed bacterial cultures

Chlorinated organophosphate ester (OPE)-degrading enrichment cultures were obtained using tris(2-chloroethyl) phosphate (TCEP) or tris(1,3-dichloro-2-propyl) phosphate (TDCPP) as the sole phosphorus source. In cultures with 46 environmental samples, significant TCEP and TDCPP degradation was observed in 10 and 3 cultures, respectively, and successive subcultivation markedly increased their degradation rates. 67E and 45D stable enrichment cultures obtained with TCEP and TDCPP, respectively, completely degraded 20 muM of the respective compounds within 6 h and also the other, although the degradation rate of TCEP by 45D was relatively slow. We confirmed chloride ion generation on degradation in both cases and the generation of 2-chloroethanol (2-CE) and 1,3-dichloro-2-propanol (1,3-DCP) as metabolites of TCEP and TDCPP, respectively. 67E and 45D also showed dehalogenation ability toward 2-CE and 1,3-DCP, respectively. Addition of inorganic phosphate did not significantly influence their ability to degrade the chlorinated OPEs but markedly increased their dehalogenation ability, which was maximum at 0.2 mM of inorganic phosphate and decreased at a higher concentration. Denaturing gradient gel electrophoresis analysis showed that dominant bacteria in 67E are related to Acidovorax spp. and Sphingomonas spp. and those in 45D are Acidovorax spp., Aquabacterium spp., and Sphingomonas spp. This analysis indicated the relationship of the Sphingomonas- and Acidovorax-related bacteria with the cleavage of the phosphoester bond and dehalogenation, respectively, in both cultures. This is the first report on bacterial enrichment cultures capable of degrading both TCEP and TDCPP.     

Dietary exposure to chloropropanols of secondary school students in Hong Kong

This paper reports levels of 3-monochloropropan-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) in a wide range of food items and estimates their dietary exposure for secondary school students in Hong Kong. Dietary exposure to chloropropanols was estimated using local food consumption data obtained from secondary school students in 2000 and the concentrations of 3-MCPD and 1,3-DCP in food samples taken from the local market. The dietary exposure to 3-MCPD for an average secondary school student consumer was estimated to be 0.063–0.150 µg kg^?1 body weight (bw) day^?1, whilst that for the high consumer was 0.152–0.300 µg kg^?1 bw day^?1. Both estimates fell below the provisional maximum tolerable daily intake of 2 µg kg^?1 bw established by the Joint Expert Committee on Food Additives (JECFA) and amounted to less than 20% of this safety reference value. The dietary exposure to 1,3-DCP for an average secondary school student consumer was estimated to be 0.003–0.019 µg kg^?1 bw day^?1, whilst that for the high consumer was 0.009–0.040 µg kg^?1 bw day^?1. The resulting margins of exposures were of low concern for human health. It could be concluded that both the average and high secondary school student consumers were unlikely to experience major toxicological effects of 3-MCPD and 1,3-DCP.     

Determination of 1,3-dichloropropanol in soy sauces by automated headspace gas chromatography-mass spectrometry.

There has been recent concern about the levels of carcinogenic chloropropanols in some soy sauces. We have devised and tested a new automated headspace GC-MS technique for the analysis of 1,3-dichloropropan-2-ol (1,3-DCP) in soy sauce and similar products. The method incorporates the use of cryogenic trapping and a deuterium-labelled internal standard. The limit of detection was 0.003 mg kg(-1). After in-house validation testing, the method was applied to soy sauce samples that had previously been analysed for the related contaminant 3-monochloropropanediol (3-MCPD). 1,3-DCP was detected in 10 of 40 sauces, all of which also contained 3-MCPD. The highest level was just >1 mg kg(-1). There was no correlation between the levels of 1,3-DCP and 3-MCPD.