ANALYSIS OF THE NONVOLATILE MAILLARD REACTION-PRODUCTS FORMED IN AN EXTRUSION-COOKED MODEL FOOD SYSTEM

An enzymic method was developed to extract the total non-volatile Mail lard reaction products from a model starch-glucose-lysine extrudate. T his method, coupled with HPLC using a diode array detector, was used t o compare the profiles of Maillard reaction products in extrudates pre pared from feedstocks with added citric acid (CA) or sodium hydrogen c arbonate (SHC). The chromatograms revealed the presence in both sample s of material that was unretained by the HPLC column as well as resolv ed peaks, but the chromatograms of the SHC sample were more complex. D iode array spectra were obtained for three and seven resolved peaks, r espectively, from the CA and SHC extrudates. All three peaks from the CA sample were also present in the SHC sample and one was 5-hydroxymet hylfurfural (HMF). (C) 1998 Elsevier Science Ltd. All rights reserved.