重组培根加工过程中N-亚硝胺及其前体物质含量的动态变化

为了明确重组培根加工过程中N-亚硝胺含量的动态变化及其影响因素,监测原料肉、腌制、蒸煮、烟熏加工环节中pH值及亚硝酸盐、生物胺、N-亚硝胺含量的动态变化,同时考察重组培根的感官品质。结果表明：随着加工的进行,重组培根pH值和亚硝酸盐残留量均呈现先上升后下降的趋势;在监测的8 种生物胺中,原料肉中仅检出精胺,随着重组培根加工的进行,生物胺的种类不断丰富,含量逐渐升高,烟熏显著加速了生物胺的生成;原料肉中仅检测出N-二甲基亚硝胺（N-nitrosodimethylamine,NDMA）和N-亚硝基吡咯烷（N-nitrosopyrrolidin,NPYR）;腌制后可检出N-甲基乙基亚硝胺（N-nitrosomethylethylamine,NMEA）、N-二丙基亚硝胺（N-nitrosodipropylamine,NDPA）、N-二丁基亚硝胺（N-nitrosodibutylamide,NDBA）和N-亚硝基哌啶（N-nitrosopiperidine,NPIP）,NDMA含量超过了国标限量; 蒸煮后新增N - 二乙基亚硝胺（ N - n i t r o s o d i e t h y l a m i n e ,NDEA）和N-亚硝基吗啉（N- n i trosomorpholine,NMOR）,且NDMA、NDPA、NDBA、NPIP含量显著升高（P＜0.05）;烟熏过程中N-亚硝胺总量显著增加（P＜0.05）,烟熏6～9 h增幅最大;重组培根的感官评分随着烟熏时间的延长显著提高（P＜0.05）。综合食用安全性和感官评分,建议制作重组培根时选择腌制16 h,热熏法（55±2） ℃烟熏6h。     

GC-FID法同时测定腌制鱼干中9种N-亚硝胺类化合物

在气相色谱-氢火焰检测器的基础上建立了同时测定腌制鱼干中9种N-亚硝胺类化合物的方法。采用碱液加热处理结合二氯甲烷萃取的方法提取腌制鱼干的N-亚硝胺,经棷壳活性炭净化,C₁₈固相萃取(SPE,Solid Phase extraction)小柱富集,样液用DB-WAXETR极性柱(30 m×0.25 mm,0.25 μm)进行色谱分离,柱温采用程序升温。结果显示:该方法下的9种N-亚硝胺类化合物在0.05~5 μg/mL浓度范围内线性良好(R2＞0. 999);检出限和定量限范围分别为0.05~0.29 μg/mL和0.18~0.95 μg/mL;回收率和RSD分别为76.8%~129.5%和2.29%~15.5%。对市售的50种腌制鱼干进行检测,N-亚硝基二乙胺(NDEA,N-nitrosodiethylamine)、N-亚硝基哌啶(NDIP,N-Nitrosopiperidine)N-亚硝基吡咯烷(NPYR,N-Nitrosopyrrolidine)检出率分别达到20%、20%、24%,只有一种样品的N-亚硝基二甲胺(NDMA,N-nitrosodimethylamine)超过国标限量规定(4 μg/kg)。     

肉制品和胃酸条件下亚硝胺合成阻断作用的研究进展

亚硝胺是一类强致癌性物质,在肉制品加工过程中可由胺类前体物和亚硝化试剂反应形成。本文综述影响肉制品中亚硝胺形成的主要因素：原料肉、加工方式、食盐和亚硝酸盐的添加量、维生素及多酚类等,重点探讨在体内胃酸条件下植物多酚对亚硝胺形成的抑制和促进作用机理。     

吹扫捕集-气相色谱-质谱法测定啤酒中8种亚硝胺类化合物

目的建立吹扫捕集-气相色谱-质谱法测定啤酒中8种亚硝胺类化合物的含量。方法啤酒通过吹扫捕集并经毛细管色谱柱分离,采用气相色谱-质谱法检测,以内标法定量。结果 8种亚硝胺类化合物(包括N-亚硝基二甲胺、N-亚硝基甲乙胺、N-亚硝基二乙胺、N-亚硝基二丙胺、N-亚硝基吡咯烷、N-亚硝基哌啶、N-亚硝基二丁胺和N-亚硝基二苯胺)在0.5~100.0μg/L的线性范围内呈现较好的线性关系,相关系数r均大于0.99。方法的检出限为0.20~0.35μg/L,平均回收率在78.1%~95.7%之间,相对标准偏差在2.5%~9.8%之间。结论该方法操作简单快捷,灵敏度和准确度均较高,可满足啤酒8种亚硝胺类化合物的检测。     

碱处理结合盐辅助分散液液微萃取GC-MS/MS检测即食鱼制品中7种N-亚硝胺

为提高N-亚硝胺的相关检测效率,建立了碱处理结合盐辅助分散液液微萃取(SADLLME)气相色谱-串联质谱法(GC-MS/MS)检测即食鱼制品中7种N-亚硝胺的新方法.样品经氢氧化钡溶液热处理,转移目标物至水溶液中,在辅助盐硫酸钠近饱和条件下,以二氯甲烷为萃取剂进行SADLLME,应用GC-MS/MS进行检测.方法检出限为0.10～0.19μg/kg,定量限为0.28～0.56μg/kg;加标水平为1、5、10μg/kg时,加标回收率为79.19％ ～117.40％,相对标准偏差为1.06％ ～10.30％.结果表明:此方法灵敏、可靠,选择性好,样品前处理简单,能够满足相关食品中N-亚硝胺检测的需要.     

The determination of N-nitrosodiethanolamine (NDELA) at trace levels in shampoos and skin creams by a simple, rapid colorimetric method

A technique is described for the rapid determination of N-nitrosodiethanolamine (NDELA) in shampoos, skin creams and similar products based on aqueous extraction, partition into ethyl acetate and colorimetric determination using the Eisenbrand-Preussman cleavage reaction.
Recoveries of NDELA added at levels of 5–100 μg kg⁻¹ to a range of shampoo and cream types ranged from 90–101%. The limit of determination for the method is 2.5 μg kg⁻¹. Observations on the application of a thermal energy analyser linked to a gas chromatograph are also reported.
Application of the technique to a survey of a wide range of shampoo and skin cream types showed that levels of total N-nitroso compounds were less than 30 μg kg⁻¹ in < 90% of samples and, in many cases, less than 2.5 μg kg -1 .
Dosage des traces de N-nitrosodiethanolamine dans les shampooings et crèmes     

Occurrence of N-nitrosodiethanolamine (NDELA) in cosmetics from the Dutch market

N-Nitrosamines as carcinogens in general pose a potential health risk. Since 1992, legal guidelines that restrict the occurrence of N-nitrosamines in cosmetics have been operational in the European Union. Problem issues are NDELA (N-nitrosodiethanolamine) and NMPABAO (2-ethylhexyl 4-(N-nitroso-N-methylamino)benzoate). Data available on the NDELA content of Dutch samples date back to the early 1980s and those for NMPABAO are lacking. For the determination of NDELA in cosmetics, a method based on capillary gas chromatography (GC) without derivatization and online chemiluminescence detection with a Thermal Energy Analyser (TEA) has been developed and validated. The sample is diluted with water, adsorbed onto a kieselgur column and eluted with n-butanol. The extract is transferred to a silica gel column which is eluted with acetone. The eluate is dried and re-dissolved in dichloromethane. The final extract is analysed for NDELA by GC-TEA. The average recovery for NDELA is 99%, range 86-112% (n = 4) and the limit of quantification is 5.3 mug kg(-1). The GC-TEA method was used to determine the NDELA content of 48 cosmetics including gels, shampoos, cremes, milks, conditioners and foams. All determinations were done in duplicate, and for every 10 cosmetics a recovery experiment and a blank determination were performed. The results of these quality assurance experiments were within the performance characteristics of the method developed. In 1996, a content of NDELA above the limit of quantification of 5.3 mug kg(-1) was measured in four out of the 48 cosmetics. Based on these results, a more selective survey was carried out. Now a NDELA content above the limit of quantification was measured in seven out of 25 sampled and analysed cosmetics.     

肉制品中N-亚硝胺检测与控制的研究进展

N-亚硝胺是一类公认的带有强毒性的化合物,是在弱酸性条件下由亚硝酸盐和二级胺反应生成的一种致癌物质,在肉制品特定的加工环境中容易生成。以往研究表明:人类是挥发性亚硝胺引起癌症的易感群体,这些物质存在于食物中被认为是某些人类癌症包括胃癌、食道癌及鼻咽癌等癌症的致病危险因子,所以国内外对食物中挥发性亚硝胺的检测、形成和控制进行了大量的研究。本文介绍了肉制品中N-亚硝胺的来源和危害;总结了该类化合物的检测方法,如气相色谱法(GC)、气相色谱质谱联用法(GC-MS)、高效液相色谱法(HPLC)等;应用辐照和天然植物等阻断剂消除和控制肉制品中N-亚硝胺技术措施的研究进展。     

碱液处理-活性炭柱固相萃取结合GC-MS/MS法检测鱼干、虾皮和虾仁中8种N-亚硝胺

建立了碱液处理-活性炭柱固相萃取结合气相色谱-串联质谱联用（GC-MS/MS）技术检测鱼干、虾皮和虾仁中N-亚硝基二甲胺(NDMA)、N-亚硝基甲乙胺(NMEA)、N-亚硝基二乙胺(NDEA)、N-亚硝基二正丙胺(NDPA)、N-亚硝基哌啶(NPIP)、N-亚硝基吡咯烷(NPYR)、N-亚硝基吗啉(NMOR)和N-亚硝基二正丁胺(NDBA)等有害物质。以NDMA-d6、NDPA-d14和NPYR-d8为内标, 用Ba(OH)₂溶液于80 ℃处理样品1 h,离心上清液,经Sep-Pak^® plus AC-2活性炭小柱富集净化,DB-WAXUI（30 m×250 μm×0.25 μm）色谱柱分离,质谱多反应监测(MRM)模式检测。结果表明,在1~200 μg/L浓度范围内,8种N-亚硝胺的线性关系良好,R²＞0.998;检出限为0.03~0.25 μg/kg, 定量限为0.10~0.85 μg/kg,添加回收率为71.3%~119.0%（除NDBA在高添加水平时略低,为52.1%~69.0%）,相对标准偏差为0.65%~15.4%。将该方法用于23种实际样品检测,在所有样品中均检出NDMA,且含量相对较高,其他N-亚硝胺仅部分检出,含量相对较低。该方法操作简单、便于高通量分析、环境友好、定性定量可靠,可为水产品中N-亚硝胺类物质的检测提供参考。     

发酵条件对香肠中亚硝酸盐和亚硝胺的影响

以发酵香肠为对象,研究了不同亚硝酸盐添加量以及发酵条件下亚硝酸盐残留和二乙基亚硝胺(NDEA)的变化规律。结果表明:各因素对香肠中亚硝酸盐残留和NDEA形成影响的大小顺序为,发酵时间>亚硝酸盐添加>发酵温度>发酵剂。正交实验分析表明:最佳发酵条件为,发酵时间2 d、亚硝酸盐添加量50mg/kg、发酵温度25℃。