Immunofluorescence detection of advanced glycation end products (AGEs) in cookies and its correlation with acrylamide content and antioxidant activity

Food processing induces protein modifications by Maillard reactions. This generates advanced glycation end products (AGEs) that are known to affect human health. Therefore, it is of interest to monitor AGEs in food products. Currently Maillard products are detected by measuring fluorescence. However, several AGEs are non-fluorescent, while non-AGE components can exhibit autofluorescence. Therefore, specific AGE immunodetection was investigated. Immunofluorescence of AGEs as well as autofluorescence were determined in cookie extracts. Autofluorescence increases with baking time and sugar level, where AGE immunofluorescence increases with baking time until 20 minutes. Replacing sucrose by fructose confirmed the higher reactivity of fructose in AGE formation. The pattern of autofluorescence correlates well with the acrylamide and antioxidant activity. However, the immunodection of AGEs did not show such a correlation. At higher baking times the autofluorescence probably results from the generation of non-proteineious compounds. The immunofluorescence reduction likely results from the transient character of AGE epitopes.