PLoS Biology a peer-reviewed, open-access journal published by the Public Library of Science has had two pieces on taste in recent months. Taste Perception: Cracking the Code by Jane Bradbury looks at how researchers are beginning to unravel the mechanisms and connections that begins with taste buds and ends in the brain. The second article The Human Sense of Smell: Are We Better Than We Think? is by Gordon M. Shepherd. Two paragraphs are especially interesting for us wine lovers.
Being carried in with inhaled air (the orthonasal route) is not the only way for odor molecules to reach the olfactory receptor cells. Odor molecules also reach the olfactory receptor cells via the retronasal route, from the back of the oral cavity through the nasopharynx into the back of the nasal cavity. Although the orthonasal route is the one usually used to test for smell perception, the retronasal route is the main source of the smells we perceive from foods and liquids within our mouths. These are the smells that primarily determine the hedonic (i.e., pleasurable or aversive) qualities of foods, and that, combined with taste and somatosensation, form the complex sensation of fl avor. It is likely, for several reasons, that this is an important route for smell in humans.
So, all you hedonists, remember to breathe out through the nose when tasting wine, or anything for that matter.
Describing a smell or a taste in words is very demanding. A professional wine tasting, for example, requires many steps: analysing both orthonasal and retronasal perception, comparing the two in memory with each other and with all other wines to be compared, identifying the constituent properties separate from the hedonic qualities, and finding the words to describe the process as it unfolds, leading to the final formulation to characterize the quality of the wine and identify it as distinct from all others. It may be characterized as hard cognitive work that only a human, among all the animals with olfactory organs, can do. It may be argued that this is what humans are adapted to do.
We evolved to describe what we taste in wine. Well that's what this eBlog and most especially this one are for.