Identification and correlation of perceived intensity and agreeability of sensory and chemesthetic taste stimuli and determination of differences between taster categories in a female non-dysphagic population

Background: Treatments dominating oropharyngeal dysphagia therapy lack evidence and are disliked by patients. A promising treatment approach where sensory and chemesthetic taste stimuli have been found to modify the swallow by heightening sensory input is currently being researched. However, the variety of possible tastes that may enhance the swallow and their palatability is understudied. Furthermore, the discovery of super, medium and non-tasters needs consideration as it is hypothesised that differences exist between the group’s perceptions of intensity and agreeability. The establishment of an oropharyngeal dysphagia treatment that can be used with all populations, ensures safe swallowing and is agreeable for patients is vital. The aims of this study are: To identify the most intense and the most agreeable perceived taste stimuli and examine correlations between them. To identify the ratio of super, medium and non-tasters in an Irish population and explore differences between them regarding perceived intensity and agreeability. To identify groups of sensory and chemesthetic taste stimuli for possible use in the treatment of oropharyngeal dysphagia. Methods: Subjects were 108 non-dysphagic female volunteers between the ages of 18 and 50. A blue dye test was administered to determine taster category status by counting fungiform papillae. The participants then completed a questionnaire rating their perceived intensity and agreeability of 54 different sensory and chemesthetic taste stimuli on 9 point scales. Results: Menthol, strong regular food, alcohol, sour and spicy taste stimuli groups were rated highest for perceived intensity. Menthol, sweet, smoky, umami, bitter and bland taste stimuli groups were rated highest for perceived agreeability. 5.56% of the participants were supertasters, 19.44% medium tasters and 75% non-tasters. One significant difference was found between perceived agreeability and taster category where non-tasters perceived fudge to be more agreeable than medium tasters (p=0.004). No difference was found between perceived intensity and taster category (p<0.05). Mild to moderate significant positive and negative correlations were found between the tastes with reliable underlying similarities were identified for intensity by factor analysis and one reliable group for agreeability. Conclusions: A number of highly intense tastes have been identified which may be of benefit in dysphagia therapy and warrant further research. Intensity may not be the only component of a taste stimulus which enhances the swallow. Palatability is subjective in nature and needs consideration in therapy on an individual basis. Taster categories in the Irish population differ from other cultures and this may be due to cultural or genetic differences. Taster status will not need consideration in therapy.