Determination of acrylamide in foods by pressurized fluid extraction and liquid chromatography-tandem mass spectrometry used for a survey of Spanish cereal-based foods

An automated and rapid method for the determination of acrylamide in different food products is presented. The method involves pressurized fluid extraction (PFE) of foods with acetonitrile and precipitation with Carrez reagents. The final extract is analysed by liquid chromatography coupled to electrospray ionization tandem mass spectrometry (ESI-MS-MS). The main parameters affecting the performance of ESI-MS-MS and PFE were optimized using a design of experiments approach. The limit of quantification of the method was 5 µg kg^-1, and recoveries from incurred samples ranged between 93 and 101%. The accuracy was evaluated using the reference test materials FAPAS T3002, T3005 and T3011. Using the optimized method, 62 food samples of potato chips, snacks, biscuits, breakfast cereals and crisp bread sampled from Valencia, Spain, supermarkets were surveyed for acrylamide levels. The levels were similar to those reported in the European Union and USA.     

Antioxidant capacity of potato chips and snapshot trends in acrylamide content in potato chips and cereals on the Canadian market

The concentration of acrylamide was measured in selected varieties of five brands of potato chips and breakfast cereals over a 5-year period. Most of the products were purchased in one locality in Canada. Samples were analysed by an isotope dilution (¹³C₃) acrylamide method. They were extracted with water, partitioned with dichloromethane, filtered through a 5 kDa centrifuge filter, cleaned-up on HLB Oasis polymeric and Accucat mixed mode anion and cation exchange SPE columns, and analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The acrylamide concentration in potato chips varied from 106 to 4630 ng g^?1, while values in cereals varied from 50 to 347 ng g^?1. Wide variations were observed between brands, within brands over time, and between lots of the same brand. A subset of potato chip samples was analysed for in vitro antioxidant activity. No relationship was found between antioxidative capacity of potato chips and their acrylamide content.     

Validation by collaborative trial of an isotope dilution liquid chromatographic tandem mass spectrometric method to determine the content of acrylamide in roasted coffee

A method for the determination of acrylamide in roasted coffee was subjected to method validation by collaborative trial. The aim was to extend the scope of a method already standardized for the determination of acrylamide in bakery and potato products to include roasted coffee. Modifications of the already standardized method were therefore kept to a minimum. The method was based on aqueous extraction of the roasted coffee matrix and solid-phase extraction (SPE) clean-up followed by isotope dilution high-performance liquid chromatography with tandem mass spectrometric detection (LC-MS/MS). The test portion of the sample was spiked with stable isotope-labelled acrylamide and extracted on a mechanical shaker with n-hexane and water for 1 h. The sample extract was centrifuged, the organic phase discarded, and a portion of the aqueous extract further cleaned-up by SPE on an Isolute Multimode cartridge followed by a second clean-up step on an Isolute ENV + cartridge. The volume of the acrylamide-containing fraction eluted from the second SPE column was reduced by evaporation and analysed by LC-MS/MS. Three coffee samples and one aqueous acrylamide standard solution were sent to eleven laboratories from eight European Union Member States. All samples were sent as blind duplicates. Based on the reported results, the relative standard deviations for reproducibility (RSD_R) were 11.5% at a level of 160 µg kg^?1, 10.1% at a level of 263 µg kg^?1, and 9.6% at a level of 585 µg kg^?1. The values for repeatability (RSD_r) in those materials ranged from 1.0% to 3.5%. The method performance parameters satisfied internationally accepted criteria. Hence, the method would be suitable for the enforcement of regulatory limits.     

Analysis of veterinary drug residues in fish and shrimp composites collected during the Canadian Total Diet Study, 1993-2004

Thirty shrimp, marine fish, freshwater fish, and canned fish composite samples collected and prepared as part of the Canadian Total Diet Study were analysed for 39 different veterinary drug residues. The analyses were undertaken to obtain baseline data that could be used to estimate the dietary exposure of Canadians to these residues. The most frequently observed residue was AOZ (four out of 30 samples), the metabolite of furazolidone, at a range of 0.50 to 2.0 ng g^-1 wet weight. Other residues detected included enrofloxacin (three samples; 0.3-0.73 ng g^-1), leucomalachite green (three samples; 0.73-1.2 ng g^-1), oxolinic acid (two samples; 0.3-4.3 ng g^-1), AMOZ (the metabolite of furaltadone; one sample; 0.40 ng g^-1), chloramphenicol (one sample; 0.40 ng g^-1), and SEM (the metabolite of nitrofurazone; one sample; 0.8 ng g^-1). The results of this survey indicate that Canadians are exposed to low ng g^-1 concentrations of some banned and unapproved veterinary drug residues via the consumption of certain fish and shrimp.     

Assessment of the acrylamide intake of the Belgian population and the effect of mitigation strategies

The acrylamide (AA) intake of the Belgian consumer was calculated based on AA monitoring data of the Belgian Federal Agency for the Safety of the Food Chain (FASFC) and consumption data of the Belgian food consumption survey coordinated by the Scientific Institute for Public Health (3214 participants of 15 years or older). The average AA exposure, calculated probabilistically, was 0.4 µg kg^?1 body weight (bw) day^?1 (P97.5 = 1.6 µg kg^?1 bw day^?1), the main contributors to the average intake being chips (23%), coffee (19%), biscuits (13%), and bread (12%). Additionally, the impact of a number of AA mitigation scenarios was evaluated (German minimization concept, scenarios for mitigation from the literature, signal values), which is an important issue for public health as well as for policy-makers. Specific actions in cooperation with the food industry to reduce the AA content of foods seems to be a more efficient strategy than mere implementation of signal values. Considering that an important share of the AA intake is due to prepared meals, the catering industry as well as consumers need to be better informed on the various possibilities for keeping the AA content of meals as low as possible.     

Distribution of diarrhetic shellfish poisoning toxins in consignments of blue mussel

Data describing the distribution of diarrhetic shellfish poisoning toxins in 13 consignments of Danish-produced blue mussels are reported. The content of diarrhetic shellfish poisoning toxins was measured by a liquid chromatography coupled with tandem mass spectrometry detection method, and mean levels in the 13 consignments varied from 58 to 243 μg kg^-1. The distributions of diarrhetic shellfish poisoning toxins in the consignments were relatively homogenous as the relative standard deviation of the content varied from 7 to 19%. The results are discussed in relation to food safety, the uncertainty of sampling and analysis, and the newly introduced European Union maximum levels of marine biotoxins in seafood products.     

高效液相色谱-串联质谱法测定动物肌肉组织中氨基甲酸酯类杀虫剂及其代谢物残留

建立动物组织中氨基甲酸酯类杀虫剂及其代谢物(共16种)残留的高效液相色谱-串联质谱分析方法。样品经乙腈提取、浓缩、净化,液相色谱串联质谱测定,内标法定量。16种杀虫剂在1.0～100μg/L范围内线性关系良好(r＞0.9959);方法定量限为0.5～2.5μg/kg;样品添加5.0、10.0、20μg/kg时,加标回收率为71.4%～105.5%;相对标准偏差为3.2%～13.7%。该方法具有简便快捷、灵敏度高的特点,适用于动物肌肉中氨基甲酸酯类杀虫剂及其代谢物残留量的检测。     

Detection of the hepatotoxic microcystins in 36 kinds of cyanobacteria Spirulina food products in China

Gel filtration chromatography, ultra-filtration, and solid-phase extraction silica gel clean-up were evaluated for their ability to remove microcystins selectively from extracts of cyanobacteria Spirulina samples after using the reversed-phase octadecylsilyl ODS cartridge for subsequent analysis by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The reversed-phase ODS cartridge/silica gel combination were effective and the optimal wash and elution conditions were: H₂O (wash), 20% methanol in water (wash), and 90% methanol in water (elution) for the reversed-phase ODS cartridge, followed by 80% methanol in water elution in the silica gel cartridge. The presence of microcystins in 36 kinds of cyanobacteria Spirulina health food samples obtained from various retail outlets in China were detected by LC-MS/MS, and 34 samples (94%) contained microcystins ranging from 2 to 163 ng g^?1 (mean?=?14?±?27 ng g^?1), which were significantly lower than microcystins present in blue green alga products previously reported. MC-RR?–?which contains two molecules of arginine (R)?–?(in 94.4% samples) was the predominant microcystin, followed by MC-LR?–?where L is leucine?–?(30.6%) and MC-YR?–?where Y is tyrose?–?(27.8%). The possible potential health risks from chronic exposure to microcystins from contaminated cyanobacteria Spirulina health food should not be ignored, even if the toxin concentrations were low. The method presented herein is proposed to detect microcystins present in commercial cyanobacteria Spirulina samples.     

Determination of malachite green residues in rainbow trout muscle with liquid chromatography and liquid chromatography coupled with tandem mass spectrometry

A method for the determination of malachite green and its major metabolite leucomalachite green in rainbow trout muscle is reported with limits of detection of 0.8 and 0.6 μg kg^-1, respectively. Residues were extracted with an acetonitrile-acetate buffer mixture and partitioned into methylene chloride. Clean-up of the extracts was performed on alumina and propylsulfonic acid solid-phase extraction columns using the automated solid-phase extraction system. The chromatographic separation of malachite green and leucomalachite green was achieved on a Chromspher 5B column using an acetonitrile-acetate buffer mobile phase. Leucomalachite green was converted to malachite green by post-column oxidation before spectrophotometric detection at 600 nm. The mean recoveries of malachite green and leucomalachite green from control rainbow trout muscle spiked at 2-50 μg kg^-1 were 65% (range 63.4-65.9%, relative standard deviation 3.9-16.1%) and 74% (range 58.3-82.6%, relative standard deviation 3.3-11.4%), respectively. Qualitative confirmation of the determined residues was performed with liquid chromatography coupled with tandem mass spectrometry detection with limits of detection of 2.5 and 1 μg kg^-1 for malachite green and leucomalachite green, respectively.     

高效液相色谱-串联质谱测定香辛料中的去甲乌药碱

建立了高效液相色谱-串联质谱(HPLC-MS/MS)快速测定香辛料中去甲乌药碱的分析方法。实验优化了样品前处理条件和色谱质谱条件。在优化条件下,样品经体积比为80%甲醇-水提取,纯水进行一定倍数的稀释,以Waters XBridge C18(150 mm×2.1mm,5μm)色谱柱分离,电喷雾正离子扫描,多反应监测(MRM)模式检测,基质匹配标准溶液外标法定量,实现了香辛料中去甲乌药碱的精确定量分析。去甲乌药碱在0.05~20.0 ng/mL范围内线性关系良好,相关系数为0.9999,方法检出限为0.7μg/kg,定量限为2.33μg/kg,在3个添加水平条件下八角的平均回收率为91.80%~99.97%,相对标准偏差为1.43%~2.35%。该方法简单、灵敏、准确性高、稳定性好,适用于香辛料中去甲乌药碱的测定。     

Kinetics of semicarbazide and nitrofurazone in chicken eggs and egg powders

The accumulation, depletion and partitioning of semicarbazide (SEM) and its parent compound nitrofurazone (NFZ) in eggs were studied using hens fed NFZ at therapeutic and sub-therapeutic levels. Dietary NFZ correlated strongly with NFZ and total SEM in eggs, while 28% of observed SEM was present in the form of parent NFZ. Depletion half-life in eggs was 2.4 days for SEM and 1.1 days for NFZ. NFZ accumulated preferentially in yolk (57–63%) as opposed to albumen, while 71–80% of SEM was found in yolk. In whole egg, 29% of SEM was present as tissue-bound residues compared with 80% in breast muscle. Whilst NFZ and SEM were partly degraded by pasteurization and spray drying, sufficient NFZ remained to suggest it might be detectable in egg powders when SEM is observed at low µg kg^?1 concentrations. NFZ was detectable in whole eggs during ingestion of only 0.1% of the therapeutic NFZ dose, making detection of intact NFZ in eggs a feasible means to prove conclusively the administration of this banned compound.     

Diarrhetic shellfish poisoning toxin esters in Danish blue mussels and surf clams

Until recently, little focus was given to the presence of diarrhetic shellfish poisoning (DSP) toxin esters in seafood products. However, during the last few years, the occurrence of a high percentage of esters of the total amount of DSP toxins present in some seafood products has been observed. Samples of Danish surf clams (Spisola spp.) and blue mussels (Mytilus edulis) from 1999-2004 were analysed by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) for the presence of DSP toxin esters. The samples contained only okadaic acid and esters of okadaic acid. The level of total okadaic acid equivalents ranged from 224 to 2516 µg kg^-1 in surf clams. The percentage of okadaic acid esters of the total okadaic acid equivalents ranged from 83 to 98%, mean 95%. The level of total okadaic acid equivalents ranged from 43 to 1631 µg kg^-1 in blue mussels. The percentage of okadaic acid esters of the total okadaic acid equivalents ranged from 21 to 86%, mean 59%. The probability of a high percentage of okadaic acid esters seems to increase with higher amounts of total okadaic acid equivalents in the bivalves. The large prevalence of DSP toxin esters are of particular importance because of the increased use of chemical methods instead of mouse bioassay for the detection of DSP toxicity.     

Methods for the analysis of melamine and related compounds in foods: a review

In recent years, two adulteration incidents concerning the addition of melamine (MEL) and related compounds to dairy products and vegetable proteins have occurred in China. These episodes prompted numerous governmental and private laboratories to develop or implement methods for the analysis of a wide variety of food products for MEL and related compounds, including cyanuric acid, ammeline, and ammelide. Methods have been developed for both screening and quantitation purposes; procedures used in the methods range from sensitive hyphenated chromatographic-mass spectrometric techniques to immunoselective assays. Various issues are encountered during the analysis of MEL and related compounds in food products. These issues include contamination, matrix effects, and analyte instability, and their severity varies according to the method used, and matrices and analytes examined.     

Overview on mitigation of acrylamide in starchy fried and baked foods

Acrylamide in fried and baked foods has the potential to cause toxic effects in animals and humans. A major challenge lies in developing an effective strategy for acrylamide mitigation in foods without altering its basic properties. Food scientists around the world have developed various methods to mitigate the presence of acrylamide in fried food products. Mitigation techniques using additives such as salts, amino acids, cations and organic acids along with blanching of foods have reduced the concentration of acrylamide. The use of secondary metabolites such as polyphenols also reduces acrylamide concentration in fried food products. Other mitigation techniques such as asparaginase pre‐treatment and low‐temperature air frying with chitosan have been effective in mitigating the concentration of acrylamide. The combined pre‐treatment process along with the use of additives is the latest trend in acrylamide mitigation. © 2018 Society of Chemical Industry     

HPLC-MS/MS测定玉米中异恶唑草酮及代谢物残留量

建立玉米中异恶唑草酮及代谢物残留量同时测定的高效液相色谱-串联质谱(high performance liquid chromatorgerphy-mass spectrometry/mass spectrometry,HPLC-MS/MS)分析法。试样用乙酸-乙腈(1:99, V/V)高速匀浆提取、醋酸钠和无水硫酸镁盐析后,提取液经N-丙基乙二胺(PSA)、十八烷基硅烷(ODS)和石墨化炭黑(GCB)净化,除去样品中脂肪和色素等大多数的干扰基质,用高效液相色谱-串联质谱仪检测,外标法定量。异恶唑草酮及代谢物的添加量在0.005～0.100mg/kg范围内,样品平均加标回收率在74.8%～107.2%之间,相对标准偏差为6.45%～11.15%;方法的检测限异恶唑草酮为0.01mg/kg、异恶唑草酮代谢物0.005mg/kg。本方法灵敏、准确、省时和操作简便,适用于玉米中异恶唑草酮及代谢物残留量同时检测和确证。     

Quantitative determination of mycotoxins in urine by LC-MS/MS

Naturally occurring mycotoxins are responsible for a wide array of adverse health effects. The measurement of urinary mycotoxin levels is a useful means of assessing an individual's exposure, but the development of sensitive and accurate analytical methods for detecting mycotoxins and their metabolites in urine samples is challenging. Urinary mycotoxins are present in low pg ml^–1 concentrations, and the chromatographic identification of their metabolites can be obscured by other endogenous metabolites. We developed an analytical method focused on the selection of two appropriate multiple-reaction monitoring transition for unambiguous identification and quantification of carcinogenic aflatoxin M₁ (AFM₁), ochratoxin A (OTA) and fumonisin B₁, B₂ (FB₁, FB₂) in urine samples from a small volunteer group in a pilot study. AFM₁, OTA, FB₁ and FB₂ were concentrated selectively, interfering substances were removed using an immunoaffinity column (IAC), and mycotoxins were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in combination with a stable-isotope standard-dilution assay (SIDA). The method was sensitive enough to measure mycotoxins and their metabolites at pg ml^–1 levels in urine. The combination of LC-MS/MS and SIDA was critical to distinguishing pseudo-OTα interference from genuine OTα. Twelve urine samples contained OTA ranging from 0.013 to 0.093 ng ml^?1 (mean = 0.031 ng ml^?1). AFM₁ were detected in one sample at a 0.002 ng ml^?1 level, while FB₁ and FB₂ were undetectable in all 12 samples. None of the samples in this pilot study contained a detectable level of OTα, despite the presence of OTA, and this may suggest the need for further epidemiological investigation of OTA exposure in the Korean population.     

液相色谱-串联质谱法快速测定食品中的可乐定

目的 采用超高压液相色谱-电喷雾串连四极杆质谱分析食品基质中的可乐定, 为可乐定中毒事件的 样本分析提供依据。方法 食物样本粉碎后经甲醇水溶液超声提取, 低温离心后, 上清液用 Waters ACQUITY UPLCTM BEH C18 色谱柱分离, 以 0.1%甲酸和甲醇溶液为流动相梯度洗脱, 最后用串联四极杆质谱在正离子 MRM 模式下进行测定。结果 以淀粉和炸鸡为加标基质, 三个加标水平下可乐定的平均回收率为 91.5%~127.8%, 相对标准偏差小于 16%, 定量限为 0.02 mg/kg。结论 该方法操作快速简单、重现性好, 成功 用于 2010 年 4 月怀柔水岸山吧可乐定中毒事件的食品检测。     

沙棘粕醇提物的定性定量分析及其对衰老小鼠肝脏抗氧化指标的影响

利用沙棘粕为研究对象,经乙醇提取、大孔吸附树脂纯化获得沙棘粕醇提物（sea buckthorn seed extract,SBSE）。利用超高效液相色谱-串联四极杆飞行时间质谱（ultra-performance liquid chromatography coupled with quadruple time-of-flight tandem mass spectrometry,UPLC-QTOF-MS/MS）对SBSE进行定性研究,通过超高效液相色谱-串联三重四极杆质谱（ultra performance liquid chromatography coupled with triple quadruple mass spectrometry,UPLC-QQQ-MS）定量分析SBSE活性成分。最后研究分析SBSE对以D-半乳糖诱导的衰老小鼠的抗氧化功效,不同浓度SBSE灌胃衰老小鼠模型42 d后,比较小鼠肝脏组织中总抗氧化能力（total antioxidant capacity,T-AOC）、谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）、超氧化物歧化酶（superoxide dismutase,SOD）和过氧化氢酶（catalase,CAT）活性以及丙二醛（malondialdehyde,MDA）和脂褐素（lipofuscin,LP）水平。结果表明：通过UPLC-QTOF-MS/MS分析方法共鉴定出24?种化合物,其中与标准品比对共确认14?种物质;利用UPLC-QQQ-MS法,采用负离子多反应监测方式,建立SBSE的14?种化合物的定量分析方法,通过检测分析,SBSE中山柰酚及其衍生物所占比例最大,质量浓度为（667.94±5.61）μg/mL;其次为槲皮素及其衍生物（（204.01±0.04）μg/mL）,原花青素类物质为（33.97±0.49）μg/mL。经过42?d的衰老小鼠灌胃实验,与模型组相比,灌胃一定剂量SBSE可以提高小鼠肝脏组织中GSH-Px、SOD和CAT的活力;低剂量组小鼠肝脏组织中的T-AOC水平极显著高于模型组（P＜0.01）;3?种灌胃剂量小鼠的肝脏组织LP和MDA含量均极显著低于模型组（P＜0.01）。     

Rapid multi-class multi-residue method for the confirmation of chloramphenicol and eleven nitroimidazoles in milk and honey by liquid chromatography-tandem mass spectrometry (LC-MS)

A confirmatory method was developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in Annex IV of Council Regulation 2377/90 (European Commission 1990) and therefore prohibited for use in animal husbandry. Milk samples were extracted by acetonitrile with the addition of NaCl; honey samples were first dissolved in water before a similar extraction. Honey extracts underwent a hexane wash to remove impurities. Both milk and honey extracts were evaporated to dryness and reconstituted in initial mobile phase. These were then injected onto a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system and analysed in less than 9 min. The MS/MS was operated in multiple reaction monitoring (MRM) mode with positive and negative electrospray ionization. The method was validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole, dimetridazole, ronidazole, ipronidazole and there hydroxy metabolites hydroxymetronidazole, 2-hydroxymethyl-1-methyl-5-nitroimidazole, and hydroxyipronidazole. The method can also analyse for carnidazole, ornidazole, ternidazole, tinidazole, and chloramphenicol. A recommended level of 3 µg l^?1/µg kg^?1 for methods for metronidazole, dimetridazole, and ronidazole has been recommended by the Community Reference Laboratory (CRL) responsible for this substance group, and this method can easily detect all nitroimidazoles at this level. A minimum required performance level of 0.3 µg l^?1/µg kg^?1 is in place for chloramphenicol which the method can also easily detect. For nitroimidazoles, the decision limits (CCα) and detection capabilities (CCβ) ranged from 0.41 to 1.55 µg l^?1 and from 0.70 to 2.64 µg l^?1, respectively, in milk; and from 0.38 to 1.16 µg kg^?1 and from 0.66 to 1.98 µg kg^?1, respectively, in honey. For chloramphenicol, the values are 0.07 and 0.11 µg l^?1 in milk and 0.08 and 0.13 µg kg^?1 in honey. Validation criteria of accuracy, precision, repeatability, and reproducibility along with measurement uncertainty were calculated for all analytes in both matrices.     

Survey of acrylamide levels in Chinese foods

A survey of levels of acrylamide (AA) in 349 food products obtained from the Chinese market was conducted. AA was determined by an liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The limit of detection (LOD) and the limit of quantification (LOQ) of the method in four different matrices ranged from 0.8 to 10 µg kg^?1 and from 4.0 to 25 µg kg^?1, respectively. The results from this survey indicated that AA was present in all samples except drinking water and tea. AA contents in different samples varied greatly according to the raw materials and processing conditions. The highest level of AA was found in potato products, with an average level of 1467 µg kg^?1. Preliminary estimates of AA exposure and risk assessment of AA from foods in the Chinese population were performed using a combination of data obtained in the present survey and 2002 dietary consumption survey carried out in 2002 for the Chinese population. The average dietary exposure of AA was estimated to be 0.38 µg kg^?1 body weight day^?1, which is relatively low compared with the result reported by the Food and Agricultural Organization/World Health Organization (FAO/WHO). Furthermore, the margin of exposure for neurotoxicity, reproductive toxicity, and carcinogenicity of AA was calculated to be 1318, 5250, and 787, respectively.