Observation of the swallowing process by application of videofluoroscopy and real-time magnetic resonance imaging-consequences for retronasal aroma stimulation

The process of eating and drinking was observed in vivo by application of v ideofluoroscopy, a dynamic X-ray technique, as well as real-time magnetic r esonance imaging. The study was aimed at elucidating the timing and perform ance of the physiological organs involved in mastication and swallowing, ma inly the tongue, the pharynx and the soft palate (velum palatinum). It was shown for the first time that effective physiological barriers do exist dur ing food consumption that are capable of retaining volatiles; such as heliu m within the oral cavity. These barriers allow the access of odorants to th e nasal cavity only at certain times during the eating process, Their effec tiveness is related to the texture of the food as well as the amount of foo d material present in the oral cavity and, thereby, directly influences ret ronasal aroma perception.