Older US Adults Like Sweetened Colas, but Not Other Chemesthetic Beverages

Many older adults suffer from difficulty swallowing thin beverages like water or coffee. To improve swallowing safety, beverages are typically thickened. This creates a new problem: the thickened beverages can be disgusting. New research suggests chemesthesis, particularly spiciness, carbonation, or intense sourness, could improve swallowing without the need for thickeners. Yet, whether such beverages would be liked by older adults is unknown. We thus conducted this experiment to establish older adults' sensory perception and liking/disliking of commercially available chemesthetic beverages. We recruited participants to rate sweetness, sourness, fizziness, stinging, and liking/disliking of unsweetened carbonated waters (1 plain, 5 flavored), sour orange juice, spicy ginger beer, and colas (sugar or aspartame-sweetened). Initial tests (N = 30 older adults) indicated sour orange juice, spicy ginger beer, and two of the flavored waters were not well-liked, so other beverages were selected for a second test (N = 94, 30 younger adults, 64 older adults). Sweetened, carbonated colas were the best-liked of the beverages. The unsweetened, flavored carbonated waters were in general not liked. Regarding comparisons of sensory ratings between older and younger adults, only sweetness differed between age groups. In particular, intensity ratings for the chemesthetic aspects of the beverages (stinging/burning/spiciness, fizziness) and the sour taste did not differ by age. As the chemesthetic properties are the most likely reason the beverages could aid in swallowing safety, observing no suppression of these sensations in older adults is encouraging for the potential of these products as a treatment option.