We here seem to run into the problem of tryng to tie a sensual perception (“concentration”) to some analytics (“dry extract”). And I’d like to argue that too many people use terms too loosely and without connection to (chemical) reality for this approach to work.
The availability of water makes for high potassium intake by the vine. Potassium is responsible for the perception of “body” in a wine. “Dry extract” strongly correlates with the acid content of must / wine, hence no one can be surprised that a high-acid year such as 2021 displays a lot of dry extract - someone upthread tried to explain this already, but the myth persists that “dry extract” is something good per se. It’s not.
What did save 2021 in Germany was the long hang time that was possible due to favorable conditions up to late fall (November). This extended physiological maturation increased the concentration (ha!) of aromatic precursor compounds in the grapes, making for very aromatic wines (potentially - you did need to harvest late!). So the best wines show quite a lot of body, very high yet “ripe” acidity, and virtually perfectly ripened phenolics, which explains the “ripe” perception of the acidity. The full body, in combination with high acidity and intense aromatics makes for the impression of “highly concentrated wines”. In 2021, some Rieslings “go to 11”.
Grape maturity could be achieved at low or high yields, depending on the condition of the canopy (health, size) w.r.t. to the fruit in need of being matured. William’s question is driven by the fact that peronospora (which is always bad) damages the canopy, thereby reducing the vine’s ability to mature even a largely reduced yield. Does it though? That depends on the “surviving” leaf-fruit ratio plus (local) weather patterns in late fall (which were highly favorable). Then, what exactly are “low yields”? Bottling a wine with 25 hl/ha after having harvested 40 hl/ha and discarded 15 hl/ha on the sorting table (or at harvest time by dropping the fruit to the ground), tells us exactly nothing about the actual conditions in the vineyard. And most vinyeard in the M-S-R region are pruned to yield much more than 40 hl/ha, more like 60 or 70 hl/ha. Mosel Riesling with residual sugar is quite robust against yields that are high (on paper), and consumers are very forgiving when it comes to perceiving too thin dry wines as “fine”, really.
Tying the impression the final wine makes in the glas (e.g., concentration) to yields, is too simple at best, and not even wrong in most cases. Evidently, at least from tastings of the finished (if very young) wines, it would appear that the vines were able to mature the grapes into something that made for a compelling wine even if a vinyard was plagued by peronospora. And there’s amplce evidence where vines have not managed that, or grapes were harvested a tad too early, or where the right balance for the finished wine wasn’t just in it because vintage.
Again, 2021 is not at all an excellent year. It’s a disastrous year where the best producers managed agains the odds (if just) to produce very good to excellent wines, the latter especially in cases where the full potential of hang time could be realized (ceterum censeo: not the Kabinetts). Whether these 2021s will turn out to be the best wines ever made, time will tell. I somehow doubt the delta to vintages like, say, 2015, 2016, 2017 or 2019 is large enough to warrant the excitement.
Cheers,
HPE