The odour/flavour of beef from animals raised on cereal concentrates differs from that of forage fed animals and this is thought to be caused, at least in part, by differences in fatty acid composition (cereals, high in linoleic acid, C18:2; grass, high in linolenic acid, C18:3). During cooking, the thermal oxidation of fatty acids produces aroma volatiles and intermediates (Mottram, 1991) that modify the Maillard reaction between amino acids and reducing sugars. In this study, we have investigated the reactions that naturally occur in the muscle during cooking by heating together a sugar (ribose), a sulphur amino acid (cysteine) and several unsaturated fatty acids to evaluate the organoleptic contribution of fatty acids to meat aroma development.