National audience; Role of lipids in the olfactive perception of dairy products Lipids hydrolysis leads to a large diversity of volatile compounds in dairy products. They contribute to the flavour characteristics of these products. On the one hand, the fat phase is a good solvent of the volatile compounds. It contributes to the flavour compound's retention. On the other hand, fatty acids, which result from lipolysis, are important in the aroma of dairy products. Not only are fatty acids aromatic compounds by themselves, but fatty acids also are precursors of methyl ketones, alcohols, lactones and esters. This paper is a review of current knowledge about the compounds that contribute to the flavour in dairy products. Discussed is the pathway of formation, the sensory properties, and quantities of the main volatile compounds encountered and also the important role of fat in flavour release.