Gunderloch's Nackenheimer Rothenbergs, Rheinhessen

I've chosen a Riesling this week as a shameless reminder that you should return to this site on Saturday to read much, much more about great Rieslings from Germany, Australia, Austria and elsewhere.

With their expanding Balbach and Gunderloch estates, Fritz and Agnes Hasselbach are on the most delicious roll at the moment, almost single-handedly doing enough to counteract the horribly bland reputation that all those flabby wines labelled Neirsteiner Gutes Domtal have earned for the Rheinhessen region on the left bank of the mighty Rhine well south of the more famous Rheingau.

They are the most significant owners of the magnificent Rothenberg site, a bank of red slate that is a continuation of the finest vineyards of what is truly Nierstein (as opposed to that ocean of Grosslage sugarwater trading on its name). Every wine sold by Gunderloch as a Nackenheimer Rothenberg has the imprint of this vineyard's earthy white peach flavour, the sort of phenomenon to warm the heart of us terroiristes. The American magazine Wine Spectator adores the Hasselbachs' rich and rare TBAs and BAs, but much better value are the wines made lower down the scale but with no less care.

The least expensive ways to savour the Hasselbach magic are via their two QbA wines. Riverside Riesling 2001 Balbach(UK retail price around £5.99) is made from fruit grown in the Niersteiner Pettenthal vineyard next door to Rothenberg vinified just off-dry with lovely open crispness (just the thing for an outdoor lunch). Nackenheimer Rothenberg Trocken QbA 2001 (£9.49) is a much more substantial dry wine with strong mineral undercurrents as well as lime flavours and real vivacity.

Nackenheimer Rothenberg Spätlese 2001 (£15.50) is in fact technically as ripe as an Auslese but from grapes without botrytis influence. It has lovely refreshing richness and honeyed character, all underpinned by a strong mineral component. It is still showing beautifully and could happily be drunk now and throughout the forthcoming summer by northern hemisphere dwellers, even though it will doubtless age for many a year yet.

The Nackenheimer Rothenberg Auslese 2001 (£21.75) will last three times as long and is also a marvel – like the most revivifying essence of Bellini (the cocktail, not the composer) you could imagine. There's an Auslese *** version (£15.50) which is much drier, very lively, taut and dense with the mineral component slightly less obvious. This would make a great food wine. And then the Auslese Goldkapsel (£42.50) from much riper, fully botrytised fruit is still extremely youthful and unfurled but a way to enjoy some of the majesty of the Beerenauslese/TBA experience without having to pay full price. Keep this one for a decade at least.

All these wines represent modest genius at work and, happily, it is not difficult to find these wines in the US according to WineSearcher. In the UK stockists include Berry Bros & Rudd, Bottletops of Putney (tel 0208 788 4752), www.gunderloch.de or nag your local wine merchant or importer.