# Wine Experiences: A Review from a Multisensory Perspective
## 2 Wine and Smell  
The integration of the senses of smell and taste is a fact, being such integration the baseline of what is known as flavor [7]. For instance, gustatory and olfactory stimuli converge in the same region of the orbitofrontal cortex [18; 19]. In this sense, [PERSON] and [PERSON] [20] suggest that flavor sensations originate principally from the integration of these two senses, where smell becomes essential for the brain while developing food preferences, and while understanding flavor [21; 22]. Indeed, olfactory stimuli, being processed via ortho, or retronasal, olfaction, are particularly important for the brain while processing a wine's flavor [23] (see [24], for an overview on the physiological role of olfactory cues on wine tasting). For example, [PERSON] et al. [25] experimentally discussed the importance of smell in the perceived bitterness and sweetness of wine. Specifically, they analyzed 30 trained wine tasters while sorting 14 samples of wine (4 commercial and 10 altered ones) across three different conditions of odorants (A--no aroma perception through nasal occlusion; B--retro-nasal perception through orthonasal deactivation; C--retronasal including involuntary orthonasal perception). The obtained results revealed that aroma perception can indeed modify sweetness/bitterness perception of red wines. The role of olfaction in wine tasting certainly becomes more intriguing when the other senses get involved in the process. For example, [PERSON] et al. [26] suggested that wine olfactory identification may be conditioned by sight, where a white wine's odor, when colored in red, tend to be identified as having the odor of a red wine (cf. [27; 28]). [PERSON] et al. [29] also conducted a similar experiment that involved wine experts, and social drinkers (again, with white wine fake-colored as red wine). Here, wine experts were able to detect the \"fake\" red wines, although their assessments related to the wine's odor were more precise when the wines were served in opaque glasses (vs. clear glasses). Social drinkers, on the other hand, where significantly deceived by the fake color of the wines during their evaluations. [PERSON] et al. [30] further analyzed the relationship between wine color and odors, using Chardonnay. This study was based on wine label matching, and conducted using projective mapping which included 3D shapes and colors. Here, they found that yellow labeling for Chardonnay tends to be a best match to buttery, citrus, floral, smoky odors when compared to more vegetable-forward type of odors. [PERSON] et al. [31] further assessed the potential interactions between shapes and odors in the context of wine tasting. In particular, 25 young participants had to rate, on Likert-scales, how well they thought 20 different odors would match with specific shapes. The findings in this study revealed an association between lemon and pepper odor with angular shapes, and between raspberry and vanilla smell with more rounded shapes. [PERSON] et al. [32] also demonstrated that the shape of the glass of wine can have a significant impact on the way tasters experience the smell of wine. In the latter study, the smell of wine was perceived as better, and more intense, when tasted in bulbous-shaped glasses [33; 34; 35]. [PERSON] [33] carried-out an experiment involving 18 blindfolded participants who had to evaluate aroma and color intensities of red and white wines when served in three different types of wine glasses as well (ISO standard, Riedel ChardonnayTM and Riedel BurgundyTM types of glasses). This study suggested that glass shape, and in particular the cuppa-diameter and cuppa-opening ratio, can affect how intense a wine's flavor is perceived (with highest intensity ratings being reported via the BurgundyTM glasses, and the lowest via the Riedel ChardonnayTM). The relationship between the taste and smell of wine was also recently investigated at different altitudes [36]. Here, two different wine tasting experiences were organized involving 22 participants.