Temporal drivers of liking for oral nutritional supplements for older adults throughout the day with monitoring of hunger and thirst status

Thomas, van der Stelt, Prokop, Lawlor, and Schlich (2016) recently introduced the Alternated Temporal Drivers of Liking (A-TDL) method in which consumers did both Temporal Dominance of Sensations (TDS) and dynamic liking evaluations on a full portion of two oral nutritional supplements (ONS) in the same session. This new study reports further development of this research in which TDS and dynamic liking were still paired at the lab, but were conducted twice a day (morning and afternoon sessions) for each product. In addition, hunger and thirst status were monitored at the lab along the successive sips and also before and after lunch and dinner at home. The objective was to reproduce the full daily experience of an ONS. A total of 62 French older adults tested the two products over two days, a week apart (a single product per day). Ten small glasses of the product were given to each participant in both morning and afternoon sessions; each one was consumed in a single sip. The protocol consisted of a TDS evaluation during each sip, followed by liking-thirst-hunger scales appearing successively. This protocol was repeated over the ten glasses. Before and after lunch and dinner, thirst and hunger status were recorded online at home. Participants seemed to be able to perform these rather sophisticated tasks quite well. Their use of the hunger scale was quite narrow and ONS consumed at the lab reduced hunger very moderately, at least compared to a regular meal being taken at home. Both products increased thirst by an average of 2 scale points along the ten sips, confirming that drinking an ONS increased thirst during tasting. Interestingly, no difference in liking was observed in the first sip, but one of the two products was slightly more appreciated on average over multiple sips. Temporal drivers of liking of this preferred product may be due to longer lasting praline and coffee-milk flavours and shorter metallic flavor and dry sensations.