Acrylamide, 5-hydroxymethylfurfural and Nε-carboxymethyl-lysine in coffee substitutes and instant coffees

Sensitive analytical methods were developed and validated for the quantification of acrylamide, N-epsilon-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 mu gkg(-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 mu gkg(-1)). None of the ICs tested in this study exceeded the indicative value set for this foodstuff (900 mu gkg(-1)). CML ranged from 0.17 to 47mgkg(-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 13gkg(-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.