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

Development of a greener and sustainable method to determine acrylamide in corn products by LC-MS/MS: Evaluation of levels in corn-based products

Acrylamide (AA) is produced through the reaction between sugars and amino acids present in starchy foods cooked at high temperature. It is classified as probably carcinogenic to humans. In 2019, the European Commission reported a list of foods for monitoring the presence of AA, which includes cereal snacks. This study presents the development and validation of an analytical approach for detecting AA in popcorn and corn-based snacks. It includes solid-liquid extraction and clean-up with dispersive solid phase extraction followed by analysis through liquid chromatography coupled with tandem mass spectrometry. The proposed method was characterized in terms of recoveries (84-105%), and precision (< 16.1%). Limits of quantification were 17 and 60 μg kg-1 for corn and popcorn, respectively. Sustainability of the methodology was evaluated using AGREEprep and BAGI, providing values of 0.43 and 65.0, respectively. Twenty-four corn-based products were analyzed, with AA levels from 219 to 418 μg kg-1.

Development and validation of LC-MS/MS method for trace analysis of acrylamide, acrylic acid and N, N-methylene bis acrylamide in sandy loam soil

Acrylamide and N, N-methylene bis acrylamide are most commonly used monomer and crosslinker compounds employed in synthesis of super absorbent hydrogels. When applied as soil conditioners, there are apprehensions that these hydrogels degrade over time and thus may release the toxic monomers in the soil. A method was thus developed using Liquid Chromatography tandem mass spectrometry (LC-MS/MS) for the trace level quantification of acrylamide (AD), acrylic acid (AA) and N,N-methylene-bis-acrylamide (MBA) in sandy loam soil amended by two test hydrogels the Pusa Hydrogel and SPG 1118 hydrogel prepared using AD and MBA. The MRM (multiple reaction monitoring) transitions were optimized for both the compounds. Soil samples were extracted using dispersive solid-phase extraction (dSPE) with a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) technique, employing acetonitrile. All analytes were quantified at trace levels within a five-minute run using UHPLC equipped with a C-18 column. Single laboratory validation of the developed method in soil matrix was conducted based on specificity, linearity, sensitivity, accuracy, precision, matrix effect and measurement of uncertainty. LC-MS/MS exhibited a linear response in the concentration range of 0.001 to 1 µg mL-1, with correlation coefficient >+0.99. Acceptable recovery (within 70-120 %) with repeatability (%RSD ≤20 %) was obtained at 0.01 to 1 µg g-1 fortification levels. LOQ (Limit of quantification) of the method for AD, AA and MBA in soil matrix were 0.05, 1 and 0.01 µg g-1, respectively. Both intra-laboratory repeatability and intermediate precision at LOQ suggested well acceptable precise (HorRat≈ 0.3) method for quantification. Matrix enhancement effect was observed in the order: AA>AD>MBA. The Expanded Uncertainty (EU) in soil matrix at LOQ was 21.64 %, 28 % and 19 % for AD, AA and MBA respectively. Groundnut and wheat grown with application of the hydrogels showed no detectable residues of monomers in soil samples (total n = 60) near the root zone at the time of crop harvesting.

Acrylamide in bread: a review on formation, health risk assessment, and determination by analytical techniques

Acrylamide is a water-soluble toxicant found in high-protein and carbohydrate-containing foods exposed to high temperature like bread as the staple foodstuff. This toxicant is mainly formed via Maillard reaction. The potential adverse effects of acrylamide especially possible carcinogenicity in human through dietary exposure necessitate its monitoring. Regarding the existence of its precursors in wheat bread formulation as well as extreme consumption of bread by most population and diversity of bread types, its acrylamide level needs to be investigated. The indicative value for acrylamide in wheat bread is set at 80 μg/kg. Consequently, its determination using liquid chromatography-tandem mass spectrometry (LC-MS/MS), gas chromatography-mass spectrometry (GC-MS), or capillary electrophoresis can be helpful considering both the risk assessment and quality control aspects. In this respect, methods based on LC-MS/MS show good recovery and within laboratory repeatability with a limit of detection of 3-20 μg/kg and limit of quantification of 10-50 μg/kg which is suitable for the immediate requirements for food product monitoring and calculation of consumer exposure.

Acrylamide in daily food in the metropolitan area of Hanoi, Vietnam

Acrylamide, a colourless and odourless crystalline solid, formed via the Maillard reaction in food, has been reported with harmful properties for humans, such as toxicity and carcinogenicity. Three hundred and four processed food samples from 17 product types, collected in Hanoi, Vietnam, were analyzed by LC-MS/MS to measure the acrylamide concentration. The limit of detection (LOD) and the limit of quantification (LOQ) of acrylamide were 1 µg Kg^-1 and 3 µg Kg^-1, respectively. Effectively, the highest acrylamide content is usually found in processed food, which is one of the primary reasons of increased acrylamide content in food. All French fried samples contained acrylamide above 500 µg kg^-1. Acrylamide concentration in non-fried noodle, vermicelli, rice noodle, phở, dried vegetable, and rice cracker is lower than in potato chips, fried potatoes, fried cake, and fried noodles. The results could be helpful to estimate exposure and risk assessment of acrylamide in Vietnam.

Monitoring of acrylamide carcinogen in selected heat-treated foods from Saudi Arabia

The present study reports the outcomes of assessment on acrylamide levels in selected heat-treated foods of diverse brands and origins from Saudi Arabia. In chips, acrylamide level was detected from 28 to 954 µg/kg, sample 7 (salted) contained higher amount (954 μg/kg) whereas, sample 8 (labneh and mint) comparatively produced lower amount (28 μg/kg). Nuts and dried fruits have generated acrylamide from 2 to 93 µg/kg, salted peanut of Indian origin produced higher amount (93 μg/kg) while apricot (plain) relatively generated lower amount (2 μg/kg). The levels of acrylamide in biscuits, pastry, cacao, chocolate, olive, cheese, corn, oat and wheat flakes, and bread were found from 26 to 234 µg/kg. Biscuits generated high concentration (234 μg/kg) while corn flakes fairly generated lower amount (26 μg/kg). The obtained results have shown a great variation of acrylamide content and reason might be due to foods type, cooking ingredients and, cooking methods, time and temperature.

Optimizing Mass Spectrometry Analyses: A Tailored Review on the Utility of Design of Experiments

Mass spectrometry (MS) has emerged as a tool that can analyze nearly all classes of molecules, with its scope rapidly expanding in the areas of post-translational modifications, MS instrumentation, and many others. Yet integration of novel analyte preparatory and purification methods with existing or novel mass spectrometers can introduce new challenges for MS sensitivity. The mechanisms that govern detection by MS are particularly complex and interdependent, including ionization efficiency, ion suppression, and transmission. Performance of both off-line and MS methods can be optimized separately or, when appropriate, simultaneously through statistical designs, broadly referred to as "design of experiments" (DOE). The following review provides a tutorial-like guide into the selection of DOE for MS experiments, the practices for modeling and optimization of response variables, and the available software tools that support DOE implementation in any laboratory. This review comes 3 years after the latest DOE review (Hibbert DB, 2012), which provided a comprehensive overview on the types of designs available and their statistical construction. Since that time, new classes of DOE, such as the definitive screening design, have emerged and new calls have been made for mass spectrometrists to adopt the practice. Rather than exhaustively cover all possible designs, we have highlighted the three most practical DOE classes available to mass spectrometrists. This review further differentiates itself by providing expert recommendations for experimental setup and defining DOE entirely in the context of three case-studies that highlight the utility of different designs to achieve different goals. A step-by-step tutorial is also provided.

Acrylamide analysis in food by liquid chromatographic and gas chromatographic methods

Acrylamide (AA) is a compound classified as carcinogenic to humans by the International Agency for Research on Cancer. It was first discovered to be present in certain heated processed food by the Swedish National Food Administration (SNFA) and University of Stockholm in early 2002. The major pathway for AA formation in food is the Maillard reaction between reducing sugar and the amino acid asparagine at high temperature. Since the discovery of AA's presence in food, many analytical methods have been developed for determination of AA contents in different food matrices. Also, several studies have been conducted to develop extraction procedures for AA from difficult food matrices. AA is a small, highly polar molecule, which makes its extraction and analysis challenging. Many articles and reviews have been published dealing with AA in food. The aim of the review is to discuss AA formation in food, the factors affecting AA formation and removal, AA exposure assessment, AA extraction and cleanup from food samples, and analytical methods used in AA determination, such as high-performance liquid chromatography (HPLC) and gas chromatography (GC). Special attention is given to sample extraction and cleanup procedures and analytical techniques used for AA determination.

Acrylamide levels in selected Colombian foods

Acrylamide (AA) levels in conventional (n = 112) and traditional (n = 43) Colombian foods were analysed by gas chromatography with mass spectrometry (GC/MS) detection. Samples included: infant powdered formula, coffee and chocolate powders, corn snacks, bakery products and tuber-, meat- and vegetable-based foods. There was a wide variability in AA levels among different foods and within different brands of the same food, especially for coffee powder, breakfast cereals biscuits and French fries samples. Among the conventional foods tested, the highest mean AA value was found in bakery products, such as biscuit (1104 µg kg(-1)) and wafer (1449 µg kg(-1)), followed by potato chips (916 µg kg(-1)). On the other hand, among the traditional foods, higher AA amounts were detected in fried platano (2813 µg kg(-1)) and yuca (3755 µg kg(-1)) compared to other products. Interestingly, the arepa, a traditional Colombian bakery product made with corn flour, showed a lower AA content (< 75 µg kg(-1)) when compared with similar bakery products tested, such as soft bread (102-594 µg kg(-1)), which is a made with wheat flour.

Determination of acrylamide in Sudanese food by high performance liquid chromatography coupled with LTQ Orbitrap mass spectrometry

A sample preparation method based on modified Quick, Easy, Cheap Effective, Rugged and Safe (QuEChERS) with aluminum oxide (Al2O3) as dispersive solid phase extraction (dSPE) material and high performance liquid chromatography-linear trap quadruple-Orbitrap-mass spectrometry (HPLC LTQ-Orbitrap MS) was established. The performance of two analytical columns namely Kinetex C18 and Rezex ROA-organic acid was compared for acrylamide separation. The method was validated in term of matrix effect, linear range (standard addition method), limit of detection (LOD), limit of quantification (LOQ), precision (RSD%) and recovery. Good linearity (r(2)>0.9979) was achieved using standard addition method in the concentration range 0-200μgkg(-1). The LOD is in the range from 2.91 to 4.04μgkg(-1) and 1.50 to 3.94μgkg(-1) for C18 and ROA columns, respectively. The precision of the method was ⩽7.3% and 5.6% for C18 and ROA columns, respectively. Recoveries of acrylamide ranging from 90% to 97%, (n=3) were obtained. The proposed Al2O3 dSPE method was successfully applied to the analysis of acrylamide in real food samples.

Sol-gel hybrid methyltrimethoxysilane-tetraethoxysilane as a new dispersive solid-phase extraction material for acrylamide determination in food with direct gas chromatography-mass spectrometry analysis

A sol-gel hybrid sorbent, methyltrimethoxysilane-tetraethoxysilane (MTMOS-TEOS) was successfully used as new dispersive solid phase extraction (dSPE) sorbent material in the determination of acrylamide in several Sudanese foods and analysis using GC-MS. Several important dSPE parameters were optimised. Under the optimised conditions, excellent linearity (r(2)>0.9998) was achieved using matrix matched standard calibration in the concentration range 50-1000 μg kg(-1). The limits of detection (LOD) and limit of quantification ranged from 9.1 to 12.8 μg/kg and 27.8-38.9 μg/kg, respectively. The precision (RSD%) of the method was ⩽6.6% and recoveries of acrylamide obtained were in the range of 88-103%, (n=3). The LOD obtained is comparable with the LODs of primary secondary amine dSPE. The proposed MTMOS-TEOS dSPE method is direct and safe for acrylamide analysis, showed reliable method validation performances and good cleanup effects. It was successfully applied to the analysis of acrylamide in real food samples.

Ultra trace level determinations of acrylamide in surface and drinking water by GC-MS after derivatization with xanthydrol

A sensitive GC-MS method has been established for the determination of acrylamide in surface and drinking water based on derivatization with xanthydrol. Deuterated acrylamide (acrylamide-d3 ) was chosen as the internal standard for analyzing the water sample. The derivatization of acrylamide was performed directly in water, and the best reaction conditions (xanthydrol of 1.6 mM, HCl concentration of 0.05 M, reaction for 30 min at ambient temperature) were established by variation of parameters. Under the established conditions, the detection and quantification limits were 3.0 and 9.7 ng/L, respectively, and the interday RSD was less than 8% at concentrations of 20 and 100 ng/L.

Analysis of currently used pesticides in fine airborne particulate matter (PM 2.5) by pressurized liquid extraction and liquid chromatography-tandem mass spectrometry

During and after the application of currently used pesticides (CUPs) a significant fraction of applied pesticides can be lost to the air. A confirmatory and rapid procedure has been developed for the determination of four fungicides (carbendazim, thiabendazol, imazalil and bitertanol), three insecticides (imidacloprid, methidathion and pyriproxyfen), one helicide (methiocarb) and one acaricide (hexythiazox) in fine airborne particulate matter (PM 2.5) at trace level. The proposed method includes extraction of PM 2.5-bound pesticides by pressurized liquid extraction (PLE) followed by a direct injection into LC-MS/MS. The main parameters affecting the performance of the electrospray ionization source and PLE parameters were optimised using statistical design of experiments (DoE). The matrix effect was also evaluated. Recoveries ranged from 86 to 106% and the limit of quantification (LoQ) was 6.5 pg m(-3) for eight out of nine pesticides, when air volumes of 760 m(3) were collected. The method was applied to 60 samples collected from four stations of the monitoring network of the Regional Valencia Government (Spain) during August-October 2007. The measured concentrations ranged from not detected to 1,371 pg m(-3).

Determination of acrylamide in coffee and chocolate by pressurised fluid extraction and liquid chromatography-tandem mass spectrometry

A selective and sensitive procedure has been developed and validated for the determination of acrylamide in difficult matrices, such as coffee and chocolate. The proposed method includes pressurised fluid extraction (PFE) with acetonitrile, florisil clean-up purification inside the PFE extraction cell and detection by liquid chromatography (LC) coupled to atmospheric pressure ionisation in positive mode tandem mass spectrometry (APCI-MS-MS). Comparison of ionisation sources (atmospheric pressure chemical ionisation (APCI), atmospheric pressure photoionization (APPI) and the combined APCI/APPI) and clean-up procedures were carried out to improve the analytical signal. The main parameters affecting the performance of the different ionisation sources were previously optimised using statistical design of experiments (DOE). PFE parameters were also optimised by DOE. For quantitation, an isotope dilution approach was used. The limit of quantification (LOQ) of the method was 1 microg kg(-1) for coffee and 0.6 microg kg(-1) for chocolate. Recoveries ranged between 81-105% in coffee and 87-102% in chocolate. The accuracy was evaluated using a coffee reference test material FAPAS T3008. Using the optimised method, 20 coffee and 15 chocolate samples collected from Valencian (Spain) supermarkets, were investigated for acrylamide, yielding median levels of 146 microg kg(-1) in coffee and 102 microg kg(-1) in chocolate.

Determination of acrylamide in coffee and coffee products by GC-MS using an improved SPE clean-up

An improved gas chromatography-mass spectrometry (GC-MS) method to determine acrylamide (AA) in coffee and coffee products was developed. The method was based on two main purification steps: the first with ethanol and Carrez solutions in order to precipitate polysaccharides and proteins, respectively; and the second with a layered solid-phase extraction (SPE) column which proved to be efficient in the elimination of the main chromatographic interferences. The method is applicable to a wide range of coffee products. Twenty-six samples of different coffee products were analysed. The levels of AA were in the range 11.4-36.2 microg l-1 for 'espresso coffee' and 200.8-229.4 microg l-1 for coffee blends with cereals. The results indicate that the presence of cereals significantly increased the levels of AA.

Analysis of heat-induced contaminants (acrylamide, chloropropanols and furan) in carbohydrate-rich food

Heat-induced food contaminants have attracted attention of both the scientific community and the public in recent years. The presence of substances considered possibly or probably carcinogenic to humans has triggered an extensive debate on the healthiness of even staple foods. In that respect, acrylamide, furan and chloropropanols are the main substances of concern. Their widespread occurrence in processed food, which concomitantly causes considerable exposure to humans, led either to the setting of maximum limits (for some chloropropanols) or at least the initiation of monitoring programmes in order to put risk assessment on a solid data basis. Acrylamide, furan and chloropropanols are small molecules with physicochemical properties that make their analysis challenging. Their amount in food ranges typically from below the limit of detection to hundreds of micrograms per kilo or even milligrams per kilo. However, a number of recently published scientific reports deal with the analysis of these substances in different kinds of food. The aim of this publication is to give an overview of analytical approaches for the determination of acrylamide, furan and chloropropanols in foodstuffs.

Acrilamida en patatas fritas y productos de aperitivo elaborados en la Comunidad Valenciana

OBJECTIVES

To evaluate acrylamide content in potato crisps and snack foods produced in the Valencian Community and to compare the results with those published by the main food safety organizations.

METHODS

Twenty-four samples of potato crisps and 15 samples of snack foods were analyzed. The results were compared with those from the Food and Drug Administration and the European Food Safety Authority.

RESULTS

The mean (SD) acrylamide level in the Valencian Community was 916 (656) microg/kg in potato crisps and 262 (346) microg/kg in snack foods. Significant differences were found in the 3 populations compared. Acrylamide levels in potato crisps in the Valencian Community were the highest.

CONCLUSIONS

There was wide variation in acrylamide content for the same type of product. Further investigation into methods of sampling and analysis and steps to reduce acrylamide levels are required.

Development of a pressurised liquid extraction and liquid chromatography with electrospray ionization-tandem mass spectrometry method for the determination of domoic acid in shellfish

Amnesic shellfish poisoning (ASP) is a potentially lethal human toxic syndrome which is caused by domoic acid (DA) that originates in marine phytoplankton belonging to the Pseudonitzschia genus. A confirmatory and sensitive procedure has been developed and validated for the determination of DA in shellfish. The proposed method includes pressurised liquid extraction (PLE) with methanol/acetone (9:1), florisil clean-up purification inside the PLE extraction cell and detection by liquid chromatography (LC) coupled to electrospray ionization in positive mode tandem mass spectrometry (ESI-MS-MS). Comparison of ionization sources (ESI, atmospheric pressure ionization (APCI) atmospheric pressure photoionization (APPI) and combined APCI/APPI) were carried out in order to improve the analytical signal. The main parameters affecting the performance of the different ionization sources and PLE parameters were previously optimised using statistical design of experiments (DOE). Linear calibrations were obtained using mussel tissue extracts 0.05-5 microg DA/ml (R2>0.999). The limits of detection (LOD) and quantitation (LOQ) of the method were 0.2 and 0.5 microg/g respectively and recoveries ranged from 81 to 95%. This method was successfully applied to determine DA levels in 46 shellfish samples collected from Valencian (Spain) supermarkets, showing high sample throughput.

Acrylamide content of selected Spanish foods: Survey of biscuits and bread derivatives

An overview of the acrylamide content in commercial biscuits and bread derivatives (bread sticks, bread crust, crackers) marketed in Spain is presented. Acrylamide was determined by stable isotope dilution LC-MS with an LOQ of 30 microg kg(-1). Acrylamide content ranged from <LOQ-2085, <LOQ-151, <LOQ-296 and <LOQ-323 microg kg(-1) for biscuits, crisp bread, crackers and bread sticks, respectively. Acrylamide was significantly higher in samples when ammonium hydrogen carbonate had been used as a rising agent and high fibre content (>5%) used in the formulation, but lower when functional ingredients, such as polyols, were used. An estimation of the acrylamide dietary exposure related to biscuits and bread derivatives was calculated as 0.082 microg kg(-1) day(-1). Estimated dietary intake were 0.002 and 0.058 microg kg(-1) day(-1) for crackers and biscuits, respectively.

Relationship between acrylamide and thermal-processing indexes in commercial breakfast cereals: A survey of Spanish breakfast cereals

Breakfast cereals are significant contributors to the daily intake of food-derived acrylamide in Western countries. Acrylamide was determined by LC-MS in 60 commercial breakfast cereals marketed in Spain. Several SPE cartridges were evaluated for clarification of the aqueous extract. LOQ was 62 microg/kg . Acrylamide content ranged from < 62-803 microg/kg (average 292 microg/kg , and median 258 microg/kg , with an estimated acrylamide intake from breakfast cereals of 2.68 microg acrylamide/person/day. According to the German concept of minimization, a signal value 450 microg/kg was calculated. Relationships among acrylamide and some parameters of the studied samples such as type of cereal, its physical form (puffed and flaked) or certain ingredients in the formulation (proteins and dietary fibre content) were also investigated. Wheat-based cereals contained significantly higher levels of acrylamide, as did samples with higher fibre or protein content. In addition, puffed breakfast cereals also contained significantly higher levels of acrylamide. There was no significant correlation between acrylamide levels and contents of 5-hydroxymethylfurfural, furosine or cereal browning.