# FaceReader Insights into the Emotional Response of Douro Wines
## 3 Results and Discussion  
### Emotional Response  
The results obtained from FaceReader for each wine sample analyzed in this section are displayed in Figure 2a-f, which illustrates the emotional profiles elicited by different types of wines, categorized as white (WW1, WW2), red (RW1, RW2), and Port (PW1, PW2). The authors analyzed the results according to the program instructions and took into account that one of the authors is a wine expert. Each emotional profile spans 12 s, covering the interval from when the sample is ingested until the microexpressions reach maximum neutrality. It is crucial to highlight that, apart from the emotions illustrated in the figure, 'neutral' was the emotion most consistently detected. The 'neutral' response was excluded from the figures to enhance our understanding of the remaining measured emotions. This exclusion was made to provide a more comprehensive analysis of the other emotional responses captured during the tasting experience. The emotions recorded are grouped into six categories: happiness, sadness, anger, surprise, fear, and disgust. The values in the figure indicate the intensity or likelihood of each emotion being exhibited at different time points during the tasting experience. White wines WW1 and WW2 show a notable sadness, especially at the initial tasting moments (1 st second, 0.244 and 0.224). This could be correlated with the acidity and freshness characteristic of white wines, which may evoke a more melancholic response than other wine types. The acidity (5.6 and 6.0 g/L tartaric acid; pH 3.4 and 3.2, respectively--Table 1) might have stimulated a sensory experience perceived as less comforting, hence the association with sadness. The sadness is typically characterized by raised inner eyebrows and lowered corners of the mouth [28] and is linked to a lowered mood, discouragement, and melancholy. Additionally, this emotion is associated with a lack of energy and a sense of fatigue [28; 29]. Furthermore, when a wine elicits an unpleasant response, such as excessive volatile acidity, which produces a vinegar-like aroma and taste, the taster will likely reject the sample and verbally request an alternative wine. This underscores how certain sensory flaws, particularly those related to acidity, can lead to negative emotional experiences and ultimately result in the rejection of the wine [13]. Figure 1: FaceReader screenshot recording the emotion “surprised”. Image retrieved from [[https://www.noldus.com/facereader/set-up](https://www.noldus.com/facereader/set-up)]([https://www.noldus.com/facereader/set-up](https://www.noldus.com/facereader/set-up)), accessed on 11 September 2024. More favorable emotions might emerge if the evaluations were extended as the taster became more accustomed to the wine and its characteristics. White wines are also the only wines in the study that manifest some gripping intensity of happiness around seconds 6 and seconds 10 and 11. This indicates that as the perception of acidity diminished due to saliva lubrication, the tasters began to appreciate more prominent flavor notes. This suggests that happiness might be connected to the satisfaction and contentment experienced when tasting these enjoyable flavors. In this study, happiness is the only positive emotion linked to feelings of contentment and satisfaction that are usually expressed through smiling [30; 31; 32]. In contrast to the white wines, red wines RW1 and RW2 exhibit a reduction in the expression of sadness. Red wines are typically fuller-bodied and richer in flavor, with less acidity (in our wines--RW1 and RW2-5.3 and 5.11 g/L tartaric acid for total acidity and pH of 3.7 and 3.96, respectively, Table 1), which may evoke a more pleasant and comforting emotional response, thereby diminishing feelings of sadness. Port wines PW1 and PW2 show a heightened response to the emotion of surprise. This could be linked to the fortified nature of these wines (19.7 and 19.4% vol., respectively,  
Figure 2: Emotional profile elicited by the wine.