*3.4. Correlation and Multivariate Analysis of Hedonic and Facial Expression Responses*

The Pearson correlation coefficient matrix (Table 6) shows the correlations between various variables (sensory attributes, overall liking, familiarity and AFER) for energy drinks A and B. Familiarity was positively correlated with overall liking (*r* = 0.44) and various sensory attributes such as the liking of taste/flavour (*r* = 0.40), sweetness (*r* = 0.38), bitterness (*r* = 0.44), mouthfeel (*r* = 0.40) and aftertaste (*r* = 0.46). The appearance of the product was negatively correlated to the facial expression of "sadness" (*r* = −0.33). The facial expression "anger" was negatively correlated with the liking of sensory attributes such as sweetness (*r* = −0.38) and aftertaste (*r* = −0.29). The results of the principal components analysis (PCA), which explains the relationship between emotions and hedonic attributes are shown in Figure 2. The principal component one (PC1) explained 31.59% of total inertia, while principal component two (PC2) explained 12.68%, respectively. The overall liking vector was positively related to familiarity, sensory attributes (taste/flavour, mouthfeel, aroma, sweetness, bitterness and aftertaste) and emotions ("disgust" and "sadness"), and negatively correlated to emotions ("joy" and "anger").




**Figure 2.** Principal components analysis (PCA) of the sensory attributes, familiarity, liking and emotions of energy drinks.
