I am a great fan of wines from the Riesling cultivar, which probably explains why I decided to mostly concentrate on this variety (I also tasted a few Pinot Noirs and the occasional Sylvaner) when I recently visited the bi-annual « Millésime Alsace » wine fair in Colmar. Luckily the day was not at all hot, which was indeed fortunate since there seemed to be no air-conditioning in the huge hall of this town’s exhibition centre. In any event, all the wines were served at the right temperature, which is not always the case at these big fairs.
I must admit to some perplexity when confronted with one particular aroma family to be found in a significant number of Rieslings: that which resembles paraffin, petrol or other aromas close to the hydrocarbon family. I have at various times in my motorcycling past been obliged to siphon petrol from one tank to another, which involves sucking up the stuff into a tube to prime the thing. It is not the greatest tasting experience in the world and I cannot truly say that any Riesling, however bad, tastes like petrol. We are talking about analogous comparisons here, and these are often approximations. Some say that these aromas can be reminiscent of truffles, but I also find them to seem a bit grassy and rough in texture. In any event I personally dislike such aromas and therefore tend to prefer Rieslings which do not show them. Very often, these aromas are also accompanied by considerable bitterness that goes with a roughish, green texture in the wines. Not all, but many. During the day I tried asking several Alsatian wine-producers for their explanations of these flavours. They all related this to a « terroir » factor, meaning, in their parlance, the geological nature of sub-soils. This I find very hard to believe as I have found hydrocarbon aromas and flavours in Rieslings from a very wide range of soil types and from different countries as well. Perhaps someone could explain to me exactly which component is common to the many soil types in Alsace and that nevertheless causes the emergence of this aroma family.
Here I will quote Michel Chapoutier, the famous Rhône producer, speaking about enological defects becoming signs of so-called « typicality » (usually a fairly meaningless concept in wine by the way).
MC: “It is interesting to ask the following question: if some characteristic taste of certain wines are historically typical from this wine, are they part of its tradition and typicality? If these tastes are the result of instability or a bacterial degradation, should they be considered part of cultural heritage of this wine? When I taste a delicious Jura “Vin Jaune”, I actually taste a wine for which oxidation and ethanalisation has been domesticated. But here, the alleged defect was so unanimous that winemakers sought to master it, make it into a rule which is now undeniable. I would not consider hydrocarbon aromas in young Riesling wines in the same category. And it is the same problem for those aromas of leather in red wines, which too often merely illustrate a contamination of brettanomyces. »
I have however noticed that the Rieslings that show these petrol-like aromas tend to come from the warmer climates and regions in which this variety grows: Alsace in warmer years and/or on the warmer slopes, or indeed Australia. So warmth and sun rays could well be a factor. A more scientific and multi-factorial explanation that includes the heat factor has been provided by someone and I will attempt to resume it here.
The carrot factor
There is a molecule called 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN for short), that is produced during the ageing process of some Rieslings (I have no precisions to offer as to the duration of this ageing) by the hydrolysis of carotenoïde aroma precursors. Which precursors tend to develop when several of the following factors occur: very ripe grapes caused by reduced yields, strong exposure to sun rays, some water stress and high acid levels. I am not sure about the ageing factor being essential as I find these aromas in young and older Rieslings, but the rest makes sense to me, especially as someone else has suggested that these aromas are produced by skin contact due to harvested grapes hanging around too long or getting mushed up before pressing.
Fortunately, many of the Rieslings that I tasted on that day were free of this unpleasant (to me) aroma, and I will give you a list of these first. If you do not find your favourite Alsace Riesling producers in this list, then there are several possible reasons: I did not have time to taste at all of the 99 stands in the fair; some stands of famous producers were too full of other tasters; in any case I was looking mainly for younger or lesser-known producers; or, naturally, their Rieslings just tasted of petrol anyway!
Domaine Agapé (Vincent Sipp à Riquewihr, see photo above): This was easily my favourite set of wines tasted at this fair. A delicate yet essentially fruity and floral style with very fine textures, totally free of any grassiness. They seemingly floated over my palate, with just a perfumes caress on the way. Delicious wines from three Grand Cru vineyards: Osterberg, Rosacker, and Schoenenbourg, from vintages between 2015 and 2017.
Pierre Adam, in Ammerschwihr, for their Riesling Grand Cru Kaepferkopf 2010.
Domaine Schoffit, in Colmar, for their Riesling Harth, and the two Grands Crus Sommerberg et Rangen, not forgetting also their remarkable Chasslas.
Domaine Armand Hurst, in Turkheim, for their Riesling Grand Cru Brand 2016 and 2014, and some other interesting wines.
Domaine Martin Schaetzel, in Kientzheim, for their Rieslings « S » 2015 and Schlossberg 2016.
Domaine Bott Geyl, à Beblenheim, for their Rieslings Graffenreben et Grand Cru Sclossberg 2014.
Domaine Stentz Buecher à Wettolsheim, for their Rieslings Tannenbuhl cuvée Flavien and Grand Cru Steingrubler « B » 2017.
Wunsch & Mann à Wettolsheim, for their Riesling Grand Cru Steingrubler (I forgot the vintage)
Domaine Zusslin, à Orschwihr, for their Grand Cru Pfingstberg 2015.
At a more accessible price level, since not of Grand Cru status I also enjoyed the wines of Domaine Ansen à Westhoffen, at cellar-door prices of around 10 euros. This producer also has the great good sense to close his bottles with screw-caps, which surely would make sense for all of these wines. Price-wise, the Grand Cru Rieslings above mostly retail for over 20 euros and sometimes over 30. They are worth these prices, but we are not talking about bargain basement here.
Altogether I tasted on that day around 80 different Rieslings from Alsace. Here are the names of the other estates whose wines I liked less: Henry Fuchs, Francis Beck, Scheidecker, Emile Beyer, Cave de Hunawihr, Baumann Zirgel, Paul Kubler, Sipp-Mack, Cave de Ribeauvillé, Gresser, Zinck, Haag.
So, long life to this potentially great grape variety, with or, preferably, without aromas that remind one of petrol!