If you haven't had wines from the Ahr be sure to check out the great insights from Dustin Chabert, Jeremy Eubanks, Blake Leja, Alex Ring, Mark Guillaudeu and inderpal singh last week.
This week: TDN in Riesling
What does the acronym stand for? How does it manifest in the glass? What causes it? Are there particular regions that display more than others?
AWRI droppin some serious science on dat gosolene smell here https://www.awri.com.au/wp-content/uploads/Sept-Oct-2012-AWRI-Report.pdf #smellslikevictory or alternatively.....#smellslikeLimeMarmalade
Interesting article, but it doesn't really deal with the fact that TDN builds up in the skins. How does pressing and skin contact affect TDN development? I don't have any hard evidence here, but there's a good contingent of winemakers out there who don't want to be too aggressive in pressing to ensure that they don't have too much TDN in their wine.
TDN isn't in the skins of the grapes - eat a riesling grape at maturity and it doesn't taste like petrol - but the *precursors* of TDN do reside in the skins, hence the gentle pressing to avoid a TDN-y wine by avoiding too many of the compounds that yeasts assemble into TDN during fermentation.
That said, what I associate as the more bitter and extracted styles of riesling (like Austrian grosse lagen) while having more phenolic content that I would associate with more rigorous pressing regimes also somehow seem to have less finished TDN character. The mystery deepens!
Correct, but I typically associate that type of extraction with ripeness as well, which you would think would lead to precursors, but not if they're able to get ripeness without overexposure to the sun. It would be interesting to see a study where they test different press regimes over a single parcel of grapes and measure TDN development.