RAFA: Chromatography is not ‘sexy’ and food contact migration

A call not to forget chromatography when it comes to analysis and work to analyse possible migration of substances in and out of food contact materials were the highlights of the final day of an international event.

Hans-Gerd Janssen from Unilever Research and Development Vlaardingen, said he often hears chromatography is ‘fully developed, mature, well established with nothing new to invent and not needed due to other methods’ but added this is not true and gave a variety of examples.

Janssen said large volume injection in gas chromatography has become more sensitive, separation of polar species by hydrophilic interaction chromatography (HILIC), UHPLC becoming faster and more sensitive, comprehensive GC x GC with more peaks and the Quick Easy Cheap Effective Rugged Safe (QuEChERS) method are examples of developments in the field.

Other methods are important and have their place but chromatography should not be forgotten, he added.

Janssen said the technique was not ‘sexy’ and the grants often went to newer techniques but when accurate and quantitative data was required it was the chosen method.

First results take a long time and a ‘quick and dirty analysis’ is not possible if results are to be good but this was an area to work on, he added.

Packaging substance migration testing

Erich Leitner, from the Graz University of Technology in Austria, gave examples of substances that need to be considered in the area of food contact materials.

Regulation (EC) No. 1935/2004 “on materials and articles intended to come into contact with food” defines requirements for food contact materials in general.

Analytes include heavy metals, PCP, PCB, PAH, UV stabilizers, photosensitizers for printing inks and varnishes, dyes (e.g. primary aromatic amines), and endocrine disruptors (bisphenol A, phthalates).

Leitner said data could be generated by worst case scenario methods, computer simulation or experimental data on food simulants.

However, worst case scenario methods often overestimate and food simulant data can take 10 days until a result.

The combination of gas chromatographic separation with mass spectrometric detection is still the gold standard for Non-Intentionally Added Substances (NIAS).

Only compounds <1000 Dalton are considered NIAS, because substances with a higher molecular weight are regarded as inert towards migration due to the large size.

Christiane Laine, VTT Technical Research Centre in Finland, told the audience about mineral oil contamination and barrier properties. 

She cited a recent analysis by Foodwatch, a non-profit organisation, which found mineral oil aromatic hydrocarbons (MOAH) in certain products.

Mineral oil contamination can come from printing inks, not being fully removed in the recycling process or from additives, lubricants and other processing aids.

Laine said they had developed a test method which will be available next year and results will be published soon.

EU policy developments

The final talk was from Frans Verstraete from the European Commission, DG for health and food safety about recent and future developments in EU policy.

One such move was around mycotoxins and the amendment of Regulation (EC) No 1881/2006 regarding setting maximum levels of ergot sclerotia in certain unprocessed cereals.

The European Food Safety Authority (EFSA) will publish scientific opinions on deoxynivalenol, moniliformin and diacetoxyscirpenol next year.

Verstraete also talked about methods of choice such as LC-MS/MS for pyrrolizidine alkaloids found in honey, herbal tea and supplements and HPLC-MS/MS for tropane alkaloids.

He said maximum levels for polycyclic aromatic hydrocarbons (PAHs) in cocoa fibre, banana chips, food supplements, dried herbs and dried spices were adopted recently and will come into force from April next year.

For heavy metals, the maximum levels of lead in food and arsenic in rice and rice products has been amended but work will be expanded to look at maximum levels for other foods. 

Discussions are also ongoing for maximum levels of mercury in fish and fish products and perfluoroalkylated substances.  

The next Recent Advances in Food Analysis (RAFA) conference will be held in 2017.