The effects of heating on colour generation measured as CIE colour space parameters of L*a*b* and acrylamide formation were studied in various food matrices including green coffee, wheat flour and potato chips at different temperatures. Changes in both the acrylamide concentration and the redness parameter a* during heating at relatively higher temperatures followed a typical kinetic pattern in which an initial increase to an apparent maximum followed by a subsequent decrease was observed. The similarities between the changes in acrylamide and redness parameter a* during heating revealed that colour may be a reliable indicator of acrylamide levels in thermally processed foods. The overall results suggest that both acrylamide and redness parameter a* form as intermediate products during Maillard reaction. Since an apparent decrease was observed in its level during prolonged heating at certain temperatures, prediction of acrylamide level in foods during processing should be based on realistic reaction mechanism, instead of simple linear regression model. (c) 2005 Elsevier Ltd. All rights reserved.