Analysis of facial expressions in response to basic taste stimuli using artificial intelligence to predict perceived hedonic ratings

PLoS One. 2021 May 4;16(5):e0250928. doi: 10.1371/journal.pone.0250928. eCollection 2021.

Abstract

Taste stimuli can induce a variety of physiological reactions depending on the quality and/or hedonics (overall pleasure) of tastants, for which objective methods have long been desired. In this study, we used artificial intelligence (AI) technology to analyze facial expressions with the aim of assessing its utility as an objective method for the evaluation of food and beverage hedonics compared with conventional subjective (perceived) evaluation methods. The face of each participant (10 females; age range, 21-22 years) was photographed using a smartphone camera a few seconds after drinking 10 different solutions containing five basic tastes with different hedonic tones. Each image was then uploaded to an AI application to achieve outcomes for eight emotions (surprise, happiness, fear, neutral, disgust, sadness, anger, and embarrassment), with scores ranging from 0 to 100. For perceived evaluations, each participant also rated the hedonics of each solution from -10 (extremely unpleasant) to +10 (extremely pleasant). Based on these, we then conducted a multiple linear regression analysis to obtain a formula to predict perceived hedonic ratings. The applicability of the formula was examined by combining the emotion scores with another 11 taste solutions obtained from another 12 participants of both genders (age range, 22-59 years). The predicted hedonic ratings showed good correlation and concordance with the perceived ratings. To our knowledge, this is the first study to demonstrate a model that enables the prediction of hedonic ratings based on emotional facial expressions to food and beverage stimuli.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anger / physiology
  • Artificial Intelligence
  • Disgust
  • Emotions / physiology*
  • Facial Expression
  • Fear / physiology
  • Female
  • Happiness
  • Humans
  • Male
  • Middle Aged
  • Pleasure / physiology
  • Sadness / physiology
  • Taste / physiology*
  • Young Adult

Grants and funding

This research was supported by JSPS KAKENHI (No. 17K00835 to T.Y.) and a Project Research grant from Kio University (No. 2018-1 to T.Y.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.