During eating, the first food transformations occur in the mouth and constitute preliminary steps of a series of reactions leading to digestion. Food breakdown occurring in the mouth contributes to the bolus formation and to the release of the stimuli responsible for the global sensory perception. However food breakdown not only depends on food composition and structure but also on human oral physiology, which could explain the high inter-individual differences observed in sensory perception and liking. After a general introduction, the presentation will focus on examples related to dairy products. Dairy products offer a great variability in terms of composition and structure and their liking depends on different sensory descriptors covering texture, taste and aroma perception. A modification of their composition and process will modify their sensory properties. However high inter-individual variability in their overall liking is noticed. They can be related to different physiological parameters (mastication, saliva flow and composition, respiratory flow, oral volume) which lead to different food bolus structure and different dynamic release of flavour compounds. The respective impact of the physiological parameters (mastication, saliva) on flavour release and perception will be discussed as a function of food composition/structure. The global sensory perception is the result of the integration of the different sensory modalities (texture, taste and aroma perception) occurring during the time of consumption and after swallowing. As fat perception is a multimodal perception involving the texture, taste and olfactive modalities, a specific focus will then be done on fat perception and liking in food-speads as a function of food composition/structure, oral physiological parameters and bolus formation.