The effects of mono- and divalent cations on the formation of acrylamide were studied in a fructose-asparagine model system at 150 and 180 degrees C. At amounts equivalent to those of asparagine and fructose, added divalent cations, such as Ca2+, were found to prevent acrylamide formation completely, whereas monovalent cations, such as Na+, almost halved the acrylamide formed in the model system. It was confirmed by mass spectrometric analyses of pyrolyzates that the formation of the Schiff base of asparagines, which is the key intermediate leading to acrylamide, was prevented by the cations. Meanwhile, the reaction proceeded to form brown coloured products. Dipping potatoes into calcium chloride solution inhibited the formation of acrylamide by up to 95% during frying. The sensory quality of fried potato strips, in terms of golden yellow colour and crispy texture, was not adversely affected by this treatment. (c) 2006 Elsevier Ltd. All rights reserved.