Automated High Throughput Objective Assessment of Human Taste Palatability Predictive of Consumption
Authors: Stewart Mariah M , Palmer R Kyle 
Published: June 2021

Psychoactive drugs are characterized by stimulus properties that generate qualitative interoceptive stimuli, and by reinforcing properties that promote or suppress drug consumption. Similarly, tastant agonists, chemicals that stimulate T1R and T2R receptors expressed in taste buds, also can be thought of as carrying stimulus properties which generate taste qualities, and reinforcing properties that impact tastant consumption. Objective measure of taste quality in both humans and animals is obtained from taste discrimination assays, but objective quantification of “palatability”—the property that determines tastant consumption—only is evident in animal models. We previously reported a high throughput automated system for human taste discrimination, the TaStation®. We have further developed the TaStation® for objective measurements of palatability that predict tastant consumption. The basis of the method is a game in which subjects spend money from a limited virtual “bank account” to create an “ideal plate”—a 96‐well plate that, from the subject's perspective, contains the best‐tasting set of samples. The samples (200 μl each) to be evaluated are randomly presented to subjects in replicates, drawn by an electronic pipette from another 96‐well plate, the “source plate.” Subjects self‐administer each sample from the pipette to the tongue, then select one of two buttons, labelled “Include” or “Exclude,” appearing on a touch‐sensitive display. A button‐touch indicates a subject's intention to include the sample in, or exclude it from, their ideal plate. A subsequent touch on a monetary scale (range = $0.00 to a pre‐set maximum) also appearing on the display indicates the price the subject will pay (withdrawn from their bank account) to actuate the inclusion‐exclusion operation. The amount spent is equated with a probability that the inclusion‐exclusion choice will be carried forward—maximum allowed expenditure buys a probability of 1.0 guaranteeing execution of the subject's choice, whereas a zero expenditure results in a probability of 0.5 that the sample will be either included or excluded. Samples for which a subject spends the highest amounts either predominate (“Include”) or are absent (“Exclude”) in the final ideal plate. Approximately half of the samples for which a subject spends nothing appear in the final ideal plate. After 96 such trials, the completed ideal plate is submitted to a computer‐generated virtual market that rewards the subject for their ideal plate creation efforts by returning a monetary value on the plate content. At the game's conclusion, the subject is remunerated in actual money for the amount remaining in their bank account and for the amount returned by the virtual market. The rewards are balanced to ensure incentive for spending the limited bank account resources toward ideal plate design. A subject's taste “preferences” can readily be discerned from the final ideal plate configuration, and the amounts spent for each tastant operationally quantifies palatability. In a series of tests, the amounts spent per sample closely mirrored actual volumes consumed by each subject measured from 30 ml samples of the same tastant solutions, thereby providing a validation of the TaStation® method for objective quantification of palatability.Support or Funding InformationFunded entirely by Opertech BioThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.