Acrylamide, 5-hydroxymethylfurfural and N^ε-carboxymethyl-lysine in coffee substitutes and instant coffees

Abstract

Sensitive analytical methods were developed and validated for the quantification of acrylamide, N^ε-carboxymethyl-lysine (CML) and 5-hydroxymethylfurfural (HMF) in 24 commercial coffee substitutes (CSs) and 12 instant coffees (ICs). Acrylamide levels varied widely from 200 to 4940 µg kg^–1 with higher levels in CSs. Only two out of 24 CSs had a level of acrylamide above the indicative value set for this food category by the European Commission (4000 µg kg^–1). None of the ICs tested in this study exceeded the indicative value set for this foodstuff (900 µg kg^–1). CML ranged from 0.17 to 47 mg kg^–1 and it increased in proportion to the protein content of the samples. The highest concentrations were found in IC partly due to the relatively high protein content of this food group. HMF was the most abundant neoformed compound (NFC) found in the tested commercial samples. It was found between 0.59 and 13 g kg^–1. Among other food categories IC and CS could appear to be major contributors to the exposure to NFCs if consumed on a daily basis. Further investigations are needed to elucidate the acrylamide formation during processing and to determine the daily intake level of frequent consumers of these products.

Graphical Abstract

Keywords:

• acrylamide
• 5-hydroxymethylfurfural
• N^ε-carboxymethyl-lysine
• coffee substitute
• chicory
• instant coffee
• HPLC-MS/MS
• Maillard reaction products

Acknowledgements

This study was financially supported by the Regional Council of Picardie and the European Regional Development Fund (France).