Instability of an aromatic amine in fatty food and fatty food simulant: characterisation of reaction products and prediction of their toxicity

Abstract

It is a well-known fact that amines are not stable in food of a fatty nature. In this study the synthesis and characterisation of the products obtained as a result of the reaction of amines in a fatty medium are reported. Based on the well-known reactions among amines and acid and esters groups, two novel compounds were synthesised using m-xylylenediamine (mXDA), a primary diamine widely used as monomer in the manufacture of food contact materials and two fatty acids, oleic acid and palmitic acid, which occur in most fats. The resulting compounds were two molecules belonging to the family of fatty acid amides, dioleamide and dipalmitamide. A complete characterisation of both products was carried out employing several techniques such as infrared spectroscopy, ¹H- and ¹³C-NMR spectroscopy, electron ionisation mass spectrometry, LC-MS/MS and UV spectrometry. The results obtained by the different techniques were well correlated. In the second part of the work, the formation of these compounds in real samples was evaluated. For this purpose a certain volume of olive oil was spiked with a known amount of mXDA. Olive oil was selected as a fatty medium since it is a widely consumed food and additionally is used as a fatty food simulant in migration studies of food contact materials. A method was developed to extract the fatty acid amides from the fatty matrix, which were then identified by LC-MS/MS. The toxicity of the synthesised compounds was predicted using a toxicity estimation software tool.

Graphical Abstract

Keywords:

• amines
• m-xylylenediamine
• food contact materials
• fatty food
• olive oil
• fatty acid amides characterisation

Acknowledgements

The authors are grateful to C. Casal, P. Blanco and G. Hermelo for their excellent technical assistance.

Additional information

Funding

The study was financially supported by the Ministerio de Ciencia e Innovación [reference number AGL/2008-04146 ‘MIGRAMIN’]. The authors are grateful to the Ministry of Science and Innovation of the Spanish Government for the Predoctoral fellowship FPI [reference number BES-2009-023016] awarded to Rafael Paseiro-Cerrato. R. Sendon is grateful to the ‘Parga Pondal’ Program financed by the Galician Government for her postdoctoral contract.