Comparison between discrete and continuous analysis of facial expressions, elicited by bitter‐tasting beverages in overweight and healthy‐weight individuals

Abstract

The aim of the present study was to compare the information provided by a discrete and continuous data analysis of two emotions (disgust and joy), elicited by bitter‐tasting beverages (coffee, yerba mate infusion and grapefruit juice) in two groups with different Body Mass Index (BMI): overweight group (25 < BMI < 30), and healthy‐weight control group (18.5 < BMI ≤ 25). Participants (n = 66; 34 females, 32 males) evaluated a total of three consecutive sips of the same beverage (taking one sip every 20 seconds (s) and registering a continuous video for 60s. The Wilcoxon test (continuous analysis) showed some changes generated as the drinks were being consumed. The biggest difference was the expression of disgust for coffee in the high BMI group, at the first sip (0‐10s). It represented 27% compared to 2% in normal BMI. The continuous analysis allowed to observe the periods where the differences were greater (0‐10 and 40‐50s).