Swiss Grapes: Räuschling — The Acid Queen

Despite an encouraging trend toward greater grapevine diversity, two varieties continue to dominate the Swiss wine landscape: Pinot Noir is here to stay, because the Swiss, like their German counterparts, fancy themselves the new masters of this sensitive, climate-threatened variety; and the much-maligned Chasselas because it’s so emblematic of Swiss culture as the workhorse wine in so many bars and cafés.

Splashing your fondue with anything else ought to be a crime.

Other varieties like Cornalin (Rouge du Pays), Humagne Rouge, Petite Arvine, Rèze and Humagne Blanche are native to Valais, and are rising stars at home and abroad, but there are three native varieties in Deutschschweiz that are sometimes lost in the Valais hustle: Räuschling, Completer and Hitzkircher.

Räuschling, in particular, is a rather puzzling variety for a few reasons. It’s often confused with its sound-alike relative, Riesling — the two share Gouais Blanc as a parent. And it has a doppelgänger in Completer; because the two were often co-planted, along with Elbling, in the 18th and 19th century vineyards of Zürich. In fact, the two are so intertwined they share a local synonym, Zürirebe. And to make things even more tangled, one of Completer’s other synonyms is Räuschling Edelweiss — doppelgänger, indeed.

Apocryphal creation stories are another point of confusion. Like the one alleging an itinerant Räuschling came to Germany from Central Europe via South Tyrol and Eastern Switzerland during the European Migration Period (circa 375-800 AD). A story roundly debunked by recent DNA analysis proving that Räuschling’s other parent is none other than Savagnin. The same Savagnin proven to be present in Central France as early as 1100 AD. That’s enough genetic and historical evidence to suggest Savagnin and Gouais Blanc co-existed in Eastern France and Southern Germany since the Middle Ages, and that Räuschling was just one of their offspring — Petit Meslier and Aubin are the others.

In any case, Räuschling was first noted in an early botanical text, Bock’s Kreüterbuch, in 1546.

The Kreüterbuch

Räuschling shares some superficial characteristics with its parents. It’s vigorous, like Savagnin, with loose bunches of thick-skinned berries. And like Gouais Blanc, it’s searingly high in acid and prone to sun burn. It prefers sunny slopes with deep soils, which perfectly describes its preferred home, the north shore of the Zürichsee, with its mix of glacial rubble and molasse rock. It’s a precocious variety, but frost hardy, and it ripens early, usually in September. It’s most at risk during floraison — it tends to drop flowers in the wind — but resists rot because of its thick skin.

The name Räuschling is either derived from the German word “rauschen“, which refers to the rustling sound of its dense canopy, or, in turn, comes from another German word “ruß“, which may be a reference to the dark, sooty-looking color of its branches.

At its best, Räuschling provides crisp drinking with delicate, muscat-like aromas of orange, lemon and lime peels, spice, and sometimes, as a novelty, the wood influence of acacia or oak. I’ve enjoyed versions from warm vintages which are textured and rounded and from cooler vintages which are lean and structured. Malolactic conversion is an either-or proposition depending on the philosophy of the winemaker. I prefer to see it completed, because the texture it imparts softens what can be an acidic mean streak in less ripe examples.

Signs of Hope

There is no doubt Räuschling thrived in the Middle Ages, but today it’s barely hanging on as a fringe variety. It last appeared in the Bundessortenliste, the German government’s roster of approved varieties, in 1929. From then on, it all but disappeared, displaced in both Germany and Switzerland by the undemanding Müller-Thurgau.

Thanks to old-vine hunters, aided by various state agricultural schools, numerous old vines and abandoned vineyard sites began to pop up in Baden, Würtemmberg and Franken. Several of them included Räuschling as part of the mix. One parcel near Karlsruhe is nearly all century-old Räuschling vines. Another in the Ortenau region of Baden consists of a mixed plantation of vines that includes Räuschling, Chasselas, Chasselas Musqué, Muscat, Riesling, Auxerrois, Pinot Gris, Pinot Blanc and Pinot Noir. And in 2003, two scientists from Geilweilerhof discovered a series of mixed plantings and abandoned sites in four locations near Heidelberg — one of which is reputed to be more than 400 years old.

Today Räuschling is considered a Swiss variety — partly because no one else claims it — even though not much remains. There are just 26 hectares in Switzerland and 20 of those are in canton Zürich. For a sense of scale, consider the following statistics: 36,000 hectoliters of Räuschling were produced in 1895, while only 600 hectoliters were produced 100 years later, in 1995. And in the decade from 2010-2020 the average production for all white varieties combined was just 15,000 hectoliters. And that includes the grape that displaced it — the aforementioned Müller-Thurgau — the most planted white grape in Deutschschweiz today.

Clones, clones, clones

Unlike Savagnin, there’s not a lot of clonal diversity to Räuschling, and that’s a bit concerning. For reasons of vine health, sustainability, and adaptability to climate change, it’s important to enhance the genetic diversity of threatened varieties. As of yet there is no conservatory to safeguard Räuschling’s most desirable clones or epigenetic bio-types — the ones best adapted to particular locales. Currently, most propagation is done via massal selection by individual growers.

Foundation Plant Services at UC Davis in California lists just one Räuschling clone, FPS 01 (group 8857), procured from the Geilweilerhof Institute in 1977. Then there is the JA clone taken from the mixed vineyards of Ortenau in Baden which is a virus free clone, of moderate vigor and excellent quality. Agroscope-Changins (the Swiss agricultural research institute with several campuses) lists a single accession, RAC 49. 

This makes the century-old vineyard near Karlsruhe and the other mixed vineyard sites as the last Räuschling holdovers in Germany, all potentially crucial sources for genetic material. That’s why a project like Jochen Beurer’s “Rettet die Reben” (Save the Vines) in Würtemmberg is so important. It’s an effort to recreate the mixed vineyards of the Medieval period — someone’s got to do it — by reintroducing the old varieties planted at the time, like Räuschling, Elbling and Gouais Blanc.

Even more obscure are the three Swiss champions of the red variant, Roter Räuschling: Diederik Michel of Weingut Diederik in Küsnacht, Noemie Schneider of Weingut Hasenhalde (who makes a rosé out of it) in Meilen, and the Hohl family of Weingut Rebhalde in Stäfa, have all dedicated a portion of their vineyards to the variety. Unfortunately, the only pure bottling is from Rebhalde, and I have yet to try it.

DFF07D6C-95E6-4C31-A5DA-ECE58B085590Räuschling on the vine.
(Photo and header photo courtesy of: Doris Schneider, Ursula Brühl, Julius Kühn-Institut (JKI), Federal Research Centre for Cultivated Plants, Institute for Grapevine Breeding Geilweilerhof – 76833 Siebeldingen, GERMANY)

The Yeast That Sleeps

In 2008, the Schwarzenbach family of Meilen — guardians of Räuschling in Switzerland — organized a tasting that may have forever altered the profile of the variety. The tasting included a cache of several bottles recovered from the rubble of a construction site. One in particular, a Meilener from 1895, caught the taster’s attention for its youthful vigor and freshness. As it happens, Dr. Jürg Gafner from the Agroscope-Wädenswil was in attendance and he took the remains of that bottle to investigate the secret to its longevity — he discovered a dormant but revivable yeast. He postulated that the holdover yeast adapted to life in the bottle and survived on residual fructose. Since saccharomyces cerevisiae prefers sucrose it’s likely the fructose remained from a stuck fermentation. This suggests, among other things, that Räuschlings from the warmer vintages of the era were sweet by default.

The current trend toward dry Räuschlings is made possible, partly, by the commercialization of Dr. Gafner’s yeast. The so-called “Sleeping Beauty Yeast” or 1895C, its commercial name, is one of the most effective fructophilic yeasts on the market. This means that stuck fermentations caused by a fructose-to-sucrose imbalance are a thing of the past and that Räuschling can be routinely fermented to dryness, if desired.

A similar tasting in 1995 focused on the ageability of the variety. Scientists at Geilweilerhof sampled seven wines from each decade between 1895 and 1995. The tasters found the Räuschlings from 1923 and 1944 to be “exceptionally good” and two from 1898 and 1959 still had “a lot of fragrance and strength.”

Whether the residual yeasts had anything to do with the results was not studied, but I suspect they might have had an impact if they chose to look.

An Overview of Some Notable Räuschlings

Schwarzenbach Weinbau, Meilen (Zürich) —  Alain Schwarzenbach has chosen to continue with his family’s study of Räuschling as interpreted by the vineyards of Meilen. It’s been a family obsession since Alain’s grandfather refused to give up on it even when its popularity plummeted in the middle of the last century. It’s a very difficult variety to get right but its potential to transcend the over-planted and overrated Muller-Thurgau as the signature white grape of Deutschschweiz is a warming thought. Schwarzenbach makes two Räuschlings: a simple AOC Zürich and the single-vineyard Seehalden.

2018 Räuschling, “Meilener-Seehalden” (Zürich): (Stainless steel; no malo-lactic) Pale yellow in color. Lovely aroma of orange zest and herbs. Appetizing flavors of spice and bergamot. Very fresh and lively. This variety is usually high in acid but in this hot vintage it displays some flesh and forward fruity qualities. Finishes with a crisp bite.

2017: Pale straw colored. Fresh herbs, white flowers and quince. Palate is restrained and almost constricted by high acids. Requires lots of aeration for the fruit to peek through. When it does it’s mostly green apple with a delicate floral lift. Hard to judge. Very linear without much flesh. ML might have helped.

2014: Straw colored. Haunting lime and lime blossom aroma. Fragrant palate is all white flowers and more lime but with slightly rounded acids. Finishes crisp and refreshing if a bit a short. This has a bit more saturation and is beginning to soften but it’s still a work in progress.

2011: Medium-straw in color. Slightly feral, in the mold of Sauvignon Blanc. More white flowers with Golden Delicious apple. Good depth with structure and length. Just beginning to show some charm. After eight years this is beginning to soften and fill out. This is a variety that requires patience.

2008: Straw colored. There is some evolution here. Floral and baking spice notes offer a promising glimpse of future development. The palate is hefty with baked apple and sweet spice flavors. Finishes customarily lean with some lingering perfume.

Weingut Besson-Strasser, Laufen-Uhwiesen (Zürich) (Nadine & Cédric Besson-Strasser) — This is an important biodynamic domaine that takes its pioneering role in Switzerland very seriously. I spoke with Cédric Besson-Strasser at Raw Wine in London and I was impressed with his candor when I asked about the slow uptake of organic and biodynamic viticulture in Switzerland. In his opinion, as I have heard from others, the Swiss are very resistant to change without financial incentive. This is not earthshaking news, as it applies to a lot of people around the world, but the frustration in his voice was palpable. He’s found it easier to form alliances with like-minded growers in France and beyond, where knowledge is shared with enthusiasm. He and his wife Nadine are in the advance guard of Swiss biodynamics and Räuschling is one of the key varieties in their journey.

2014 Räuschling, vom Rheinfall (Zürich): Pale silver color. Floral, sylvaner-like nose with verdant green notes. Palate is light-weight with significant acids. Very fresh and simple at the moment with some lingering floral perfume and a slightly reductive minerality. This variety is hard to evaluate when young. Older examples can be quite exciting.

Weingut Pircher, Stadtberg Eglisau (Zürich) — The Eglisau master, Urs Pircher, is set to retire at the end of the year. Already groomed to replace him is his godson, Gianmarco Ofner. Gianmarco is expected to guide Weingut Pircher into biodynamic farming with a renewed commitment to Räuschling and a new one to Riesling. For an overview of the Eglisau vineyards with a discussion of Pircher and Matthias Bechtel (below) see: TRINK Magazine.

2015 Räuschling, Eglisau (Zürich): Pale straw/green in color. Very simple, green apple nose. Bright and clean to boot. Surprisingly soft palate with a bit of cream and crisp apple fruit. I was told there was no malolactic fermentation, which belies the softness of the palate. I liked this quite a bit and thought it to be one of the best young Räuschlings I’ve tasted. Warm vintage accounts for the softness and texture.

Bechtel-Weine, Eglisau (Zürich) — This is the new kid on the block, or should I say the Stadtberg. He is already making waves with bought in fruit but he is hard at work reorganizing his part of the hill, with municipal support, so that in future his grapes will be entirely estate grown. His treatment of Räuschling is unique and already turning some heads, if not attracting some sideways glances.

2019 Räuschling, Eglisau (Zürich): Straw gold in color. Surprisingly complex nose of tropical fruit, apple and sawdust from raw acacia wood barrels. This is one of the most textured Räuschlings of my experience. It’s almost opulent. The fruit flavors, mostly mango and passion fruit, are focused and powerful. The acids seem well in check but are welcome in the finish, which is bright, fresh and lengthy. A new direction for Räuschling?


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