It wasn't until this spring that I realised there was something aloof with the 2014 vintage in Germany, but since then I've experienced this same off-putting note in a few too many German Rieslings, though astonishingly it seems to be limited to just this vintage. Today after having the similarly afflicted but still thankfully quite scrumptious Günther Steinmetz Dhroner Hofberg 'GD' I finally had a brain wave and linked it to a previously experienced aroma which is that dull and slightly rancid note of an empty and corkless wine bottle forgotten in the cupboard for a couple weeks or more.
The best theory I had was that it might be because of the heavy botrytis (the less than noble kind) of the vintage, and after today it still makes sense as the botrytis-damaged berries in the vineyards would obviously be extremely susceptible to oxidation. However, the similarly wet 2013 vintage seems to be completely unafflicted by this flaw, so I'm not completely sure what to make of it.
Since my realisation I have naturally been rather wary of buying much more of the vintage, and I have kept close track of wines opened. Here are the wines I've noticed this flaw in so far, all limited to the 2014 vintage:
Günther Steinmetz Dhroner Hofberg Riesling 'GD'
Dönnhoff Kreuznacher Kahlenberg Riesling Trocken
Fritz Haag Brauneberger Juffer Riesling Feinherb
Fritz Haag Brauneberger Riesling Trocken 'J'
Lubentiushof Gondorfer Gäns Riesling Trocken
And wines without:
BattenfeldSpanier Hohen-Sülzen Riesling Trocken
Weiser-Künstler Trabener Gaispfad Riesling Kabinett Trocken
Schwedhelm Schwarzer Herrgott Riesling Trocken
Schwedhelm Wotanfels Riesling Trocken
Kruger-Rumpf Münsterer Kapellenberg Riesling Trocken
Dreissigacker Bechtheimer Riesling Trocken
Anyone with similar experiences or maybe thoughts about possible causes?