Sour taste and cold temperature in the oral phase of swallowing in patients after stroke.

PURPOSE To determine the effect of sour flavor and cold temperature on oral transit time during swallowing. METHODS Participants were 52 subjects (28 male and 24 female) with ages between 50 and 80 years (median=66 years), after ischemic stroke involving right or left side damage and mild to moderate oropharyngeal dysphagia. Videofluoroscopy was performed to analyze the swallowing times. Each subject was assessed during swallowing of a paste consistency bolus offered in 5 ml spoons, with a total of four different stimuli (natural, cold, sour and sour-cold). After the exam, the oral transit time was measured using specific software. The oral transit time (starting at the beginning of the bolus movement in the mouth) and the total oral transit time (starting at the moment that the bolus is placed in the mouth) were measured. RESULTS The association between sour and cold stimuli caused a significant decrease of oral transit time and total oral transit time. CONCLUSION Sour flavor and cold temperature reduced oral transit time in stroke patients.