(Academicwino) - How a wine tastes is dependent upon many factors, including (but not limited to) the variety, the vintage, where the grapes are grown (soil, climate, etc), as well as the viticultural and winemaking techniques employed during processing.  The compounds responsible for how wine tastes are known as free volatile compounds, as well as aromatic precursors, the latter of which are present at much higher concentrations.  Non-volatile sugar-bound conjugates (a.k.a. “glycosidic compounds) have been well studied and have been shown to be released over time during wine aging or by using specific winemaking techniques. Specific glycosidic compounds known to be released over time, thus affecting how a wine develops and tastes, include terpenes, C13 norisoprenoids, benzenic derivatives, volatile phenols, and C6 compounds.  All of these glycosidic compounds have low

odor thresholds, thus requiring very little to elicit a sensory response.

While wine aromatics have been extensively studied, it is not well known exactly how compounds responsible for aromatic character in wines interact with the physiological make-up of the human mouth. In addition to environmental and chemical sources, it is possible that the perception of different wine aromas can be altered by physiological factors like mouth temperature, saliva composition, or the oral microbial community present in each individuals’ mouths. Studies focusing on onions, bell peppers, and grapes found that the microbial community in the human mouth hydrolyzed odorless compounds into their corresponding volatile aromatic compounds, giving reason to believe something similar could potentially happen with wine.  Perhaps the microbiota living in the human mouth can hydrolyze these odorless precursors and convert them into their corresponding aromatic compounds, just like it’s been shown with other foods.

A 2015 study in the journal Food Chemistry aimed to evaluate whether or not human oral microbiota can convert odorless aromatic precursor compounds in wine into their corresponding aromatic glycosidic compounds. The results could potentially have a profound impact on our understanding of how we taste and evaluate wines.