Analysis of the non-volatile Maillard reaction products formed in an extrusion-cooked model food system

An enzymic method was developed to extract the total non-volatile Maillard reaction products from a model starch–glucose–lysine extrudate. This method, coupled with HPLC using a diode array detector, was used to compare the profiles of Maillard reaction products in extrudates prepared from feedstocks with added citric acid (CA) or sodium hydrogen carbonate (SHC). The chromatograms revealed the presence in both samples of material that was unretained by the HPLC column as well as resolved peaks, but the chromatograms of the SHC sample were more complex. Diode array spectra were obtained for three and seven resolved peaks, respectively, from the CA and SHC extrudates. All three peaks from the CA sample were also present in the SHC sample and one was 5-hydroxymethylfurfural (HMF).