But first, let us take a step back. As the wines matured in their barrels, the reds were better than many had expected — much rot had to be triaged I was there , but the result seemed worth it. Only conjecture of-course. It might also explain why some found a nasty green aroma early in the elevage, before it was coverd masked by barrel extracts….
The latest description comes mainly from french tasters who describe the aroma of gentian flowers — it sounds lovely, but you have been warned! I no longer find it in the typical Who is affected? Close to everyone and no-one depending on your sensitivity. Later tastings, but smaller samples, had a majority showing the effect. Some people, as ever, are significantly more sensitive to it — I seem to be able to pick it up at very low levels. For those of low sensitivity, this remains a relative bargain of a vintage.
What is it? Pyrazines also brings us back to our cute little beetle friends. The linked report in the third paragraph above shows that coccinella use methoxy-pyrazines as sexual attractants, they are also used as a defence alert — pick one up and the yellow colour that they leach onto your fingers also contains pyrazines. This group of naturally ocurring compounds have long been found in grape-juice and wine; some varieties like Savignon Blanc derive a portion of their characteristic aroma profile e.
This class of compounds can be detected by the humble human nose at incredibly low concentrations, not unlike those other unwelcome guests in your wine-glass, TCA and Geosmin.
Although the human nose can detect these at extremely low levels, there is considerable variation not only from person to person, but also the same person depending on the time of day. Human beings can detect pyrazines in vanishingly small amounts, such as parts per trillion.
