Terroir as Unique as a Fingerprint

A study out of Argentina and published in Nature's Scientific Reports has found that each terroir imparts on a wine a specific set of chemical components. In other words, if you had a database of chemical components from each vineyard and through such fancy techniques as gas chromatography and or mass spectrometry, you were able to obtain the chemical composition of a wine you were drinking, you could identify the vineyard of origin, at least to the extent that it was a single vineyard wine. In other words, it's how the vineyard imparts its DNA.

This raises a lot of questions. First off, what is terroir? It's a French term, not surprisingly, that has been incorporated into the English langage, at least as fas as wine is concerned. In a nutshell, it's everything about where the grapes were grown -- the soil, the topography, the exposure to sunlight, and the underlying climate. Of course, some people might have a slightly different definitiion, but that's pretty good for our purposes. 

No two vineyards have identical terroir. And, in fact, in the case of a large vineyard, the terroir will change or evolve throughout the vineyard, but there is still usually a tremendous consistency within a vineyard. And, when Domaine XYZ bottles wine from ABC Vineyard, it mixes those grapes anyway. So, truly, with respect to that vineyard, the terroir is consistent, even if blended. Where it differs some is in the case of a large vineyard in which blocks are used for particular wines or even more to the point, where blocks are leased to different wineries. But, that is way too detailed for our purposes anyway.

Let's move out of the ultra-technical for a second and into establishing that some folklore really is true. Some wine experts are known as super-tasters and can identify the vineyard from which the grapes for a particular wine come with remarkable accuracy. Lots of people never believed that can be done. But, now we know that if their senses are acute enough and they have the memory to go with it, they have a basis, in fact, to be that discerning. Essentially, they are identifying the fingerprint of the wine primarily with their senses of taste and smell, running that fingerprint through the database in their mind, and making an identification. That's pretty cool, at least to me.

The particularly study used even a more expansive definition of terroir. It included the himan influence on the wine as part of terroir. While this is strange in the American wine industry, in Europe where winemaking duties have often been passed from father to son and in more recent years often from mother to daughter, so is the knowledge of the vineyard and the specific techniques of that estate. SO, when the winemaking duties are passed down at your favorite estate or your bucket list estate, the wines will not change.

The model that was used in the research uses three main components -- volatile compounds, phenolic compounds, and sensory profiles. The combination gives each wine a unique fingerprint. Initially, the study was done on a single vintage (2011), but was later expanded to another vintage to see if the fingerprint had changed or not. The answer was that it had not.

What they don't know yet is whether the fingerprint changes with age. We know that wines evolve over time. Even with the best cork, some small levels of oxygen enter a wine causing the wine to mature. Fruit flavors decrease and earth tones come to the fore. So, the question then is what part of the fingerprint remains? Could we use technology to find a random container of wine from hundreds or thousands of years ago and identify where the grapes came from? Will you be the first wine drinker to send your wine to wineancestry.com or 23andwine.com?