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But the appropriate answer is "They're delicious, aren't they?"
Gemischter Satz are special wines from Austria's capital city of Vienna. Made from a blend of white grapes that are grown together in the field, then picked and fermented at the same time, there was a point not too long ago when the mania for "single varietal" bottlings threatened this age-old tradition of Austrian field blends. Happily, the tradition was maintained, the grapes remained planted in gloriously mixed vineyards of Gruner Veltliner, Weissburgunder, Riesling, Muscat Ottonel, and other grapes. Few Gemischter Satz bottlings specify the grapes within, and none that I've seen can give you varietal percentages. Don't worry--go for it.
I'm a relative newbie to the wines of Austria, but I can't recommend Gemischter Satz highly enough. If you enjoy crisp, food-friendly whites--and are a bit tired of the same-old same-old that you've been drinking lately seek out one of these wines and perk up your tired tastebuds.
2008 Weingut Rotes Haus Gemischter Satz Classic Nußberg ($20) This tasted very much of a Gruner Veltliner to me, with its white pepper, salt, and grapefruit aromas. The flavors of apple, grapefruit, and pepper confirmed my initial impression and the aftertaste was interesting--like sour apples. Very good QPR.
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2007 Weingut Hajszan Gemischter Satz Weissleiten ($18) This stunning organic and biodynamic wine had unmistakable aromas of freshly ground black pepper, with floral notes. The flavors turned melony, with a zing of quince, and remained dry and refreshing. The juicy, lively aftertaste kept you reaching for the bottle. This is the kind of wine that invites you to spend the evening with it, discovering the flavors that are magically contained within it. Excellent QPR.
2008 Weingut Christ Wiener Gemischter Satz ($16) This wine had piercing aromas of apple, salt, and lemon. The flavors are equally intense, with loads of minerality and stone to accompany the slightly bitter lemon at its core. A fresh and citrusy wine. Excellent QPR.
2008 Zahel Gemischter Satz Schloss Schönbrunn (NA as of yet in the US) This restrained, elegant wine had faint aromas of lemon and peach. Dry flavors reminiscent of Meyer lemon dominate the palate, and there is a touch of bitter orange follows in the aftertaste. Well worth seeking out--and I hope an American retailer snaps this up.
Note: I've been sent some corrections and have made them in the body of the text above. The wines themselves all come from within the city limits of Vienna, and Weingut Hajszan's wine is certified organic and biodynamic.
Also, if you are looking for these wines, retailers are popping up in the comments to say they have these sometimes-hard-to-find bottlings. So check below if you are interested in purchasing, as the usual online wine search engines are not always exhaustive.
Full Disclosure: I received these wines as samples.