Food packaging and contact material compounds can migrate from the polymeric materials used in food and beverage packaging into the foods and beverages themselves. A packaging component should not release chemicals that can accumulate in the food or beverage product in quantities sufficient to present a risk for the consumers. Discover our solutions for the testing of these packaging chemicals in food and beverage samples.
Food and beverages arrive on the supermarket shelf in a number of packing forms. This can be in cardboard, paper, various forms of plastics and metal, to name a few. The food contact material itself is the inner-most coating that is in direct contact with the food stuff or beverage. It can interact strongly with any surface that it comes into contact with and negatively impact the quality of the product.
Food stimulants are simplified food models intended to mimic the migration of compounds from food contact materials into real foods. The advantage of using stimulants is that broad categories of foods and beverages are able to be tested. Many regulations have employed food stimulants to a set specific migration limit (SML). However, as methodology and instrumentation have advanced, the ability to measure migration into foods has evolved rapidly.
There are a number of regulations within the USA through the Food and Drug Administration, packaging and food contact substances (FCS) code of Federal Legislation (CFR) - 21 CFR 174 - 21 CFR 190), within the European Union and within individual countries such as the German BfR and Canada, Australia and Japan, that govern the permitted levels of migration of chemicals into products. As such levels of chemicals and composition of the compounds must be determined analytically using gas chromatography – mass spectrometry (GC-MS).
Migration is the process of compounds leaching from the food contact material into the food or beverage. These can be monomers or polymer additives. The EU 10/2011 listing for plastics specifies over 1000 compounds that are permitted to be used in food contact material, the overall migration limit (OML) is used for substances that migrate from the food contact material directly to the food. Products are also subject to specific migration limits (SML), these substances are identified using analytical techniques.
Unfortunately, no packaging material is entirely inert; glass, paper, plastics and ceramics can all leach chemicals into food and drinks at significant concentrations for example, a lid on a glass jars or bottles may contain plastic and result in phthlates leaching into the product.
There are also number of significant factors that can affect the rate and type of compounds that migrate into food and beverages, these include temperature, time, the food type (fats, oils, dry foods), and the size of the packaging itself.
Due to the size of the pores in various packaging materials the analytes of interest are either volatile or semi-volatile (<1000 Da) in nature, and are therefore well-suited to analysis by GC-MS having the advantages of chromatographic resolution, reproducibility, peak capacity and, importantly, extensive spectral libraries to aid in identification.
Non-intentionally added substances (NIAS) are compounds such as impurities, reaction intermediates, breakdown products of polymer/additives and contaminants from recycling. They are found in food and beverages through inadvertent migration from food packaging such as plastics. Intentionally added substances (IAS) are known and permitted added substances found within food and beverage products, (EC) Regulation No. 1935/2004, and are rigorously controlled.
|IAS: Intentionally added substances
|NIAS: Non-intentionally added substances
As a condition of EU Regulation 10/2011 for plastics, NIAS compounds must be measured. However, when investigating NIAS in food and beverages, the analysis can be challenging as there is very little information of the potential chemicals involved.
Therefore, for NIAS, the approach taken needs to be as non-selective as possible to determine the maximum information both quantitative and qualitative, as possible to also identify known and unapproved substances, those that can be detected and not identified, and those that are simply not detected and enter the food chain.
There are a wide range of powerful analytical techniques available for the detection of targeted and known NIAS.
For the detection of both known and unknown NIAS compounds, more robust techniques must be employed to test stimulants, packaging, or foodstuffs in targeted and non-targeted analysis.
In such incidences, detectors such as mass spectrometry triple quadrupole (QQQ) combined with full-scan high resolution accurate mass (HRAM) are required, complimented by automatic data processing and ever growing compound databases. These techniques can be used for volatiles analysis through to non-volatile analysis.
Visit our food analytical testing page on food contact materials to find out more about the instruments we offer for your analyses.
Looking at the migration of compounds from packaging materials to food products can involve multiple types of applications depending upon the compounds being studied. First, samples need to be extracted from the packaging materials, then they need to be analyzed based on their volatility—volatile, semi-volatile or non-volatile. An additional analysis that may be run is for elemental impurities in the packaging that could be transferred to food products. Learn more by opening the sections below.
Accelerated solvent extraction is often used when testing food packaging materials, food contact materials, and food samples, and analysing for semi-volatile and non-volatile compounds. It is a particularly efficient technique to reliably extract compounds from polymeric materials. Conditions can be carefully controlled to ensure that the material is not deformed or damaged during the extraction process.
The technique, ideal for high-throughput labs, uses organic acids and aqueous solvents or acids and bases at high temperatures to increase the extraction efficiency of analytes, and high pressures to keep the solvents in a liquid state to extract compounds from solid and semi-solid samples quickly, using small solvent volume. This ultimately saves time, solvent, and money, and can generate results in a fraction of the time compared to traditional techniques such as Soxhlet or sonication.
The ASE technique takes 15–30 minutes and on average uses only 10–30ml of solvent, infiltrating the matrix more effectively so that certain types of incurred residues are extracted more effectively, and thus more accurate results may be obtained.
Low molecular weight, non-polar organic compounds in food contact materials are typically volatile and have the highest probability to migrate from or through polymeric contact material. Testing of the contact material is typically conducted by headspace sampling followed by gas chromatography and mass spectrometry (GC-MS).
Headspace GC-MS is a popular analytical technique and has been widely used in food packaging studies as it provides analytical advantages of chromatographic resolution, reproducibility, peak capacity and, importantly, extensive spectral libraries to aid in identification. Gas chromatography high resolution mass spectrometry (GC-HRMS) is becoming increasingly popular, enabling the identification and quantification of unknown compounds.
Volatiles are released from materials using headspace sampling. USP methods suggest the use of valve-and-loop headspace sampling systems. Ultraclean Thermo Scientific Chromacol headspace vials help ensure low background and leak free seals.
Modular GC allows your choice of injectors, together with helium saver options and the widest range of advanced column technologies, including Thermo Scientific TraceGOLD GC column phases for volatiles.
Sensitive mass spectrometry delivers both quantitation and qualification of volatiles. Thermo Scientific ISQ Series Quadrupole GC-MS features a new source design ideal for continuous high-throughput operation.
Simple to operate and fully compliant Thermo Scientific Dionex Chromeleon Chromatography Data System (CDS) software provides mass spectrometry data acquisition and processing for GxP environments.
Semi-volatile compounds in food contact material are among the most frequently detected migration impurities. Phthalates, or phthalate esters, are used in PVC production as softening agents and are typically and legally used within food packaging, though their usage is strictly monitored and restricted in the EU. Read the blog on BPA, Phenols and Phthalates.
Testing is performed through liquid injection of an extract of the material or product. The extract is often acquired through automated sample extraction techniques, such as accelerated solvent extraction, which only takes up to 30 minutes. Following simple liquid extraction and concentration, extracts are derivatized to increase analyte volatility.
Testing demands absolute confidence in unknown identification and quantification. Solvent extraction followed by gas chromatography mass spectrometry (GC-MS) for semi-volatiles is the typical workflow for these types of compounds. Unknown semi-volatile compounds can also be detected using gas chromatography high resolution mass spectrometry (GC-HRMS)—an increasingly common technique.
Ultra clean Thermo Scientific MS Certified vials help ensure the lowest backgrounds to reduce false positives.
Simplify preparation with accurate, automated sample handling. Prepare standards, spike samples and automate derivatization with the Thermo Scientific TriPlus RSH Automsampler. With built-in robotics that deliver exceptional precision, flexibility, and reliable operation.
Absolute confidence in your analyte identification is required. Demand HRAM GC-MS with <1ppm mass accuracy, femtogram sensitivity and 6 orders linear dynamic range.
Perform targeted screening, routine quantitation, and qualitative review of data with Thermo Scientific TraceFinder software. Use advanced high resolution filtering (HRF) algorithms to provide a new dynamic in confident identification of unknowns.
Non-volatile impurities are among the most difficult to identify in food contact materials and food packaging. Ever-changing polymer additives and monomers represent an ongoing analytical challenge. Confident identification using a range of targeted libraries or advance high resolution accurate mass (HRAM) cloud based spectral libraries simplify the workflow.
Thermally instable or non-volatile constituents like isocyanates or primary aromatic amines are preferably analyzed via liquid chromatography (LC). Solvent extraction followed by liquid chromatography mass spectrometry (LC-MS), for polar and non-volatile substances is a typical analysis workflow.
Monomers, such as styrene used to make polystyrene are typically analyzed using LC-MS technologies. There could be residual levels of unreacted styrene monomer in the polystyrene, such residue is incidental and the residual monomer does not serve any useful function in the polymer.
High resolution mass spectrometry (LC-HRMS), is now typically being applied in order to identify targeted and non-targeted non-volatile compounds in packaging materials, food simulants and the final end products themselves.
Robust chromatographic separations are delivered by Thermo Scientific Vanquish UHPLC system with orthogonal detection techniques such as charged aerosol detection, providing universal coverage for unknowns, complementing MS identification.
Quick exchange ionization modes including APCI & ESI are complemented by fast polarity MS switching. Record both +/- scans within a single acquisition for complete ionization coverage. MSn capabilities and exceptional mass accuracy, make the Thermo Scientific Q Exactive Series of mass spectrometers the perfect tool for structural elucidation of unknowns.
Thermo Scientific Compound Discoverer software helps ensure confident compound identification and structural elucidation with advanced algorithms that quickly process and identify changes between different sample groups, and identify compounds based on multiple search approaches. This includes HRAM libraries, cloud based libraries like mzCloud, and compound databases. The software conducts parallel searches and delivers a single unified report.
Elemental impurities are common in printed materials, pigments, and foil-based packaging used for food contact material. There are also cases for testing lead and cadmium in ceramics. Another impurity of concern are nanoparticles. They range between 1 and 100 nanometers (10−9 and 10−7 meters) in size, and have become part of food packaging technology due to their unique properties. Packaging containing nanoparticles can extend food’s shelf life, reduce the need for preservatives, and provide non-stick, easy-clean surfaces.
Read the blog post Nanoparticles in Food Contact Material: Essential Facts.
Robust, compliant analysis at the lowest levels is provided by ICP-MS or ICP-OES. Acid digestion is followed by ICP-MS for trace elements.
Automation of the lab workflow has taken a step forward with integration of intelligent auto-dilution, which eliminates manual intervention and helps increase productivity.
The Thermo Scientific iCAP RQ ICP-MS delivers simplicity, productivity and robustness, combined with the flexibility for unattended 24/7 operation in routine, compliant environments.
Designed to comply with the most rigorous data audit and security measures, Qtegra ISDS software is FDA 21 CFR Part 11 ready and comes with full IQ/OQ procedures for simple implementation in GMP/GLP regulated environments.
Food Contact Materials Industry Resource Guide. Learn about worldwide regulations for food packaging and contact materials.
This white paper describes the issue of chemicals migrating into food from packaging materials, the need to assess the safety of those chemicals that migrate, and the role that high resolution mass spectrometry has to play in the related analysis.
See the diverse materials that come into contact with food during processing, transport, storage, packaging, and handling—in the home and during cooking.
|Food contact Material Industry Resource Guide
|Analysis of Benzophenone and 4-
|Rapid Qualitative and Quantitative Analysis of Residual Solvents in Food Packaging by Static Headspace Coupled to GC-FID/MS
|Extractables and Leachables Workflow – Identify all Suspects
|Analysis of Benzophenone and 4-
|Determination of Phthalate Esters in Soft Drinks By GC-MS
|John Gilbert Q&A on Food Contact Material: Analytical Challenges in Measuring Migration from Food Contact Materials
|Food Packaging Safety - Challenges in Food Packaging Analysis Migration
|Food contact materials - Applications summary compendium
|Sample Preparation, Mass Spectrometry
|SPME-GC-MS/MS for Identification and Quantification of Migration Contaminants in Paperboard Food Packaging
Access a targeted collection of scientific application notes, case studies, videos, webinars and white papers for food microbiology, manufacturing and processing, beverage testing, analytical testing, and authenticity information.