Gernot Kollmann, director and cellar master at Immich-Batterieberg, forwarded me his report on the 2010 vintage, my translation below. The photograph is from Gernot of grapes picked in Batterieberg. By the way, Gernot’s first vintage at the estate, 2009, is exceptional.
There are essentially three defining factors for the 2010 vintage:
1. It was an extremely small harvest. That it would be so small, I was already sure of in late August, after the grapes were—as they say—“in wine.” It became clear then that even the young vines at the foot of the slope had achieved only a small thickness of the grape skins. This is often the basis for a very good vintage, but in combination with the botrytis resulted in a “total economic meltdown.” We had only about 20 hl/ha. With other estates, which work similarly with low yields, it looks more or less the same.
2. The botrytis had “found a home,” fostered by some extreme warm and wet September days, particularly the ripest [most precocious] sites. It was in those parcels with an especially good ripeness level due to yields and in those with too much nitrogen supply. The infection [botrytis] came quite suddenly and due to its late arrival could no longer be stopped.
In terms of timing, it was between the so-called noble and sour rot [the latter infects unripe bunches], which has led to the rare situation of very high must-weight levels alongside extremely high acidity—botrytis berries have up to 18 grams per liter [!]. Atypical for such an early botrytis is that it tastes rather clean. There will indeed be many unique sweet wines, that is wines needing a relatively long maturity [in bottle] and with a fairly dry, sweet-sour expression. The top sites with slightly richer soils, more often on the lower third of a slope, or how Markus Molitor says his “crown jewels,” were most affected by botrytis this year. At Immich-Batterieberg, the perfectly south-facing sites with more top soil, such as in Steffensberg, were more affected than the stony, arid plots in the southwest-facing plots in Batterieberg or Ellergrub, where we harvested healthy grapes to the very end. I couldn’t tell real differences between conventional (with or without botryticides) and organic viticulture. [Gernot began in 2010 to work organically.] The character of the sites was more defining (incidentally, also an experience from 2006, when chemicals seriously failed…).
3. The third significant factor is the high acid levels. On the one hand, as described under the second point, the high levels came from the early concentration of the botrytis, but on the other hand, the year was already geared to a late picking, when the main Riesling harvest takes place on the Mosel, not until the last week of October, or (better) the first week of November, so the trade-off between saving quantity and gaining maturation of the remaining healthy grapes often led to panic among wineries. Many vintners also noticed that from the third week of October the botrytis had not spread, so that with healthy grapes one could calmly poker a bit. We harvested several lots with a pH of 3.1, which one can live with, and more acidity will precipitate later on.
Our strategy in this vintage was to pick early with a small group of harvesters the botrytized bunches and to vinify these separately, which was also done because of the specific needs during pressing these grapes and the other [natural] methods of clarifying the musts. But then I added the botrytized bunches from this first passage with the healthy grapes, that way they could co-ferment, leading to a “lighter” style of wine than when one beefs up a wine with BA [Beerenauslese] or subsequently includes all botrytized grapes without special handling into the mix. We were also able to let healthy grapes hang longer and to allow for a few hours of pre-fermentation maceration, which further reduces the acidity. Even in this year, we didn’t de-acidify, and I think we have attractive musts in the cellar. Meanwhile, all the wines have begun to [spontaneously] ferment, and I rely on a rather final and warm fermentation, because I want to achieve a good glycerin output (makes the wines softer, smoother, and longer) and the resulting, larger yeast population helps with clarification and reduction, and thus goes against the more oxidative botrytis vintage characteristics—malolactic fermentation this year is not to be expected of wines without de-acidification. That’s the theory at least, let’s wait and see what happens.