AN IMMUNOLOGICAL APPROACH TO MONITOR PROTEIN LACTOSYLATION OF HEATED FOOD MODEL SYSTEMS

Poly-L-lysine, a high molecular weight synthetic compound with a large number of free amino groups, was glycated with lactose through the Ma illard reaction (MR). Polyclonal mouse and rabbit antibodies (Abs) wer e obtained and characterised by competitive ELISA (enzyme-linked immun e assay), immunoblotting and cytofluorimetric assays. Results demonstr ated that the Abs react specifically with lactosylated food proteins, i.e. bovine serum albumin (BSA) and casein and do not cross react with the underivatised proteins. The immunoreactivity between Abs and lact ose-BSA adducts was strongly inhibited by N-epsilon-deoxy-lactulosyl-L -lysine, indicating that this typical MR product is recognised specifi cally by our Abs. These reagents can be a useful tool to monitor the M R reaction between carbohydrates and lysine, which occurs during the t hermal treatment of food. Copyright (C) 1996 Published by Elsevier Sci ence Ltd.