Determination of Acrylamide in Processed Foods
A requirement for many food processors is to understand the levels of acrylamide in their products and to reduce those levels if possible. Acrylamide is a process contaminant that forms in starchy foods when they are baked, roasted, or fried. A reaction between an amino acid and reducing sugars, known as a Maillard reaction, is the main chemical process that leads to the formation of acrylamide. Acrylamide may be found in a number of different foods, including French fries, roast potatoes, potato crisps/chips, biscuits, and coffee.
Waters acrylamide analysis consumable kits include consumables for the extraction, clean-up, and separation of acrylamide from processed foods by LC-MS/MS. The kits support food testing laboratories by providing a simple workflow that can reduce the need for extensive method development.
In 2015 the European Food Safety Authority (EFSA) published a risk assessment on acrylamide in food. The conclusion of this assessment was that acrylamide levels in food could lead to an increased risk of cancer for all age groups. However, no estimate on how much the risk is increased could be determined.
European Union (EU) regulation 2017/2158, which came into force in April 2018, establishes mitigation measures and benchmark levels for reducing the presence of acrylamide in food. To support actions to reduce acrylamide levels, large food manufacturers are expected to conduct representative sampling and analysis to assess mitigation measures.
The U.S. Food and Drug Administration (FDA) has issued guidance that outlines the current recommendations for reducing acrylamide levels in certain foods. The guidance from the FDA recommends that food companies are aware of the levels of acrylamide in their products and, if feasible, adopt approaches to reduce those levels.
Testing for acrylamide in processed foods
The analysis of acrylamide in processed foods has several analytical challenges to consider, which include:
- Retention: Acrylamide is a polar, low molecular weight compound.
- Matrix complexity: Extraction and clean-up are required for a range of complex processed food samples, which can greatly vary in composition.
- Concentration range: The EU benchmark levels differ depending on the food type and can range from 40 µg/kg in baby food to 4000 µg/kg for coffee substitutes, exclusively from chicory.
Acrylamide levels in food are often determined either by liquid chromatography (LC) or gas chromatography (GC) as the separation technique, coupled with mass spectrometry (MS) for detection. Due to the complexity of processed food samples, sample extraction and clean-up can often involve labour-intensive methods. Prior to analysis by gas chromatography, samples also require derivatization, which is often achieved using bromination. LC-MS methods do not require this derivatization step, saving analyst time.
Sample preparation (extraction and clean-up) for acrylamide testing in food by LC-MS/MS
Liquid chromatography coupled with tandem quadrupole mass spectrometry (LC-MS/MS) is an established technique for the analysis of acrylamide in processed foods. Legacy LC-MS/MS methods often involve sample preparation with a lengthy, multi-step solid phase extraction (SPE) clean-up. An example of a multi-step SPE clean-up procedure using Oasis SPE cartridges is outlined in the application note acrylamide in potato chips.
Alternative sample preparation methods using QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction with dispersive solid-phase extraction (dSPE) or pass-through SPE clean-up can result in faster sample preparation methods. The application note Determination of Acrylamide in Processed Foods using ACQUITY UPLC I-Class and Xevo TQ-S micro outlines an example sample preparation workflow that uses a modified QuEChERS extraction with different options of SPE clean-up prior to analysis by LC-MS/MS.
When selecting which clean-up method best meets your analytical method goals, in terms of cost per sample, recovery, repeatability, time, and resources, it is also important to consider the impact reduced sample clean-up could have on your analytical column and LC-MS/MS system. If less clean-up is achieved from the sample preparation step, this might impact column lifetime and system uptime. In the application note Investigation of the Xevo TQ-S cronos System’s Robustness for the Determination of Acrylamide in Processed Potato Chips, system performance was assessed over 500 consecutive injections of potato chip matrix. For this study, the potato chip samples were extracted and cleaned up using the Waters Acrylamide LCMS Enhanced Clean Up Kit.
Isobaric Interferences impacting quantification of acrylamide
A 2019 paper in the Journal of Chromatography A by Desmarchelier A, Hamel J, Delatour T, identified the presence of other compounds that can interfere with the quantification of acrylamide in certain samples, such as coffee. In this paper the authors identified that in-source fragments of n-acetyl-β-alanine, 3-aminopropanamide and lactamide could cause an over estimation of the acrylamide levels, if the compounds co-elute with acrylamide.
As a result of this publication, Waters application chemist Janitha De-Alwis carried out further work to assess whether these compounds co-elute with acrylamide using the method developed on the ACQUITY UPLC HSS C18 SB column, which is part of the Waters acrylamide analysis kits. The findings of this work can be found in the application note Determination of Acrylamide: Are You Avoiding Isobaric Interferences?
Protecting brands with accurate and reliable food and beverage testing workflows
Waters’ instrument, chemistry, and service solutions enable food testing laboratories to develop efficient testing methods, supporting food manufacturers in ensuring:
- The accurate monitoring of acrylamide levels in processed foods
- Acrylamide mitigation measures can be assessed for effectiveness
- (2021) Acrylamide. https://www.efsa.europa.eu/en/topics/topic/acrylamide
- EUR-Lex. (2017) Commission Regulation (EU) 2017/2158 of 20 November 2017 establishing mitigation measures and benchmark levels for the reduction of the presence of acrylamide in food. https://eur-lex.europa.eu/eli/reg/2017/2158/oj
- S. FDA. (2021) Acrylamide. https://www.fda.gov/food/chemical-contaminants-food/acrylamide
- European Committee for Standardization (CEN). (2015) Food analysis – Determination of acrylamide in food by liquid chromatography tandem mass spectrometry (LC-ESI-MS/MS). EN 16618:2015
- Desmarchelier, A, Hamel, J, Delatour, T. (2020) Sources of Overestimation in the Analysis of Acrylamide in Coffee by Liquid Chromatography Mass Spectrometry. Journal of Chromatography A. 1610(460566).