“Petrol” is a flaw in young Riesling: Olivier Humbrecht
The petrol note sometimes found in young Riesling is a flaw according to Olivier Humbrecht. And we lack a better vocabulary for the petrol note that many Riesling aficionados cherish in older bottles.
The winemaker at Zind-Humbrecht in Alsace who makes 40 different wines a year commented in New York last week that the petrol note can be symptomatic of three things. The first is harvesting under-ripe grapes. Riesling needs 110 to 120 days to ripen, he says, and harvesting the grapes too early can lead to an undesirable aroma. Similarly, he says that machine harvesting can lead to off-aromas in the wine, generally called “petrol.”
Second, Riesling is prone to reduction, a condition devoid of fruit aromas, and this can be mistaken as “petrol.” Instead, it is simply not desirable. Winemaking decisions such as making the wine in airtight environments such as stainless steel or even old oak can, poor use of sulfur, or leaving the wine on the lees can make it prone to reduction. A good winemaker should be able to see these problems arising and take steps to mitigate them.
Third, there is a desirable form of “petrol” in mature Riesling but Olivier says the term is “ill-chosen.” Given the choice, he would describe an earthy character as truffle instead of mold, as it’s a more desirable to choose term. Similarly, he prefers to think of mature Riesling as having a character of wet stones, minerals, sea air, or iodine, all of which are more pleasurable than the bottom of a diesel tank.
“I hope to God that nobody would think that young Rieslings smell like petrol!” Wine drinkers should trust their gut instinct and if the wine’s aromas are off-putting, then it is bad. Another way to tell if it is reduction: drop a copper penny into the wine (or swirl a copper wire) and see if the off-aromas disappear and fruit reemerges. Or try decanting it.
On June 14th, 2011 at 9:20 am ,Michael wrote:
What would he consider the dividing line between young Riesling and old Riesling?
On June 14th, 2011 at 9:31 am ,bill marsano wrote:
Mr. Z. wants a euphemism? Let him try ‘crushed pineapple.’
On June 14th, 2011 at 9:50 am ,Lego wrote:
Interesting! I’ve been a part of several blind Riesling tastings that included Australian Rieslings. These wines almost always had a petrol note and I’ve been told by sommeliers that this note in a young wine is a commong give away for an Australian Riesling. I wonder what he would say about this?
On June 14th, 2011 at 11:28 am ,Robin C wrote:
This is very interesting. It changes the way I think of rieslings.
On June 14th, 2011 at 12:17 pm ,Mike wrote:
Interestingly, the International Riesling Foundation says petrol notes come not from underripe grapes, but from ripe grapes harvested at low yields, and that “warmer climates, such as Alsace, will tend to exhibit the petrol character earlier in their post-bottling development.” Specifically, they say it’s “caused by the compound 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN), which during the aging process is created from carotenoid precursors (terpenes) by acid hydrolysis.”
Others say petrol is most apt to be apparent in middle age, and it eventually fades.
And then there’s Chapoutier, who says it’s caused by the “decomposition of the veins within the grape” and that it’s always a flaw. “Riesling should never smell of petrol. That is a result of a mistake during winemaking.”
It seems we have not reached consensus on this subject…
On June 14th, 2011 at 1:43 pm ,Steve Edmunds wrote:
I think we need more teapots if we’re going to contain this tempest!
On June 14th, 2011 at 2:16 pm ,Anatoli Levine wrote:
I’ve had German Rieslings with petrol smell (St.Urbans-hof QbA, for instance), but it tasted perfect, of course. I never thought of it as a flaw, but rather as a characteristic of German Rieslings.
On June 15th, 2011 at 12:15 am ,Thomas L wrote:
I’ve been told by the people who introduced and educated me to wine that prestigious Rieslings often presented these notes. My experience growing, I could make my own opinion that indeed it is most often found in rieslings from grands crus (alsace), or renowned producers, therefore in wines that have a strong terroir – or soil – expression. I thereby link this petrol arome to minerality, but I usually qualify it in function of its quality and intensity: minerality in rieslings can, for me, be either very pleasant or very heavy/invasive.
On June 15th, 2011 at 11:08 am ,Peter in Niagara wrote:
Petrol in a young riesling is a mistake, minerality (petrol) in an old riesling is sublime.
On June 15th, 2011 at 11:23 am ,Christine wrote:
I’m not qualified to have an opinion about whether a whiff of petrol is a defect, but I have always been amused by it as a descriptor and wonder if it sounds as unflattering in Europe as referring to a “gasoline” note here would be.
On June 15th, 2011 at 11:39 am ,In his cups... wrote:
I like the term: “Fusel” the aroma of oil soaked foundry sand used in casting metal, along with the Petrol-Hydrocarbons you get in lab work or syphoning gas for your motorcycle. Though sensory linked, to me petro and mineral expression are separate ,they just hang out together in rieslings allot. I have little problem with it, and find it in the new and old world. I pick it up in some Whiskies occasionally.
On June 15th, 2011 at 3:26 pm ,Peter Birmingham wrote:
A copper penny? Do you know how difficult it is to find any copper in a penny minted after 1963? Better off go to the hardware store and get 2 cm copper piping.
On June 15th, 2011 at 3:48 pm ,Josh Stein wrote:
I haven’t made as many Rieslings as M. Hembrecht, but I have made or helped with almost a decade of North Coast releases–from Napa, Mendocino, Lake, and Carneros–and can say only this: we need more discrimination of the terms “petrol” and “minerality” if we are to make headway as producers and marketers of Alsatian varietals. I think you will find other producers elsewhere have said as such before. It’s chicken-and-egg: we need more people to purchase and enjoy these wines so as to spur more development of techniques and critical vocabulary, and those techniques are what will help spread the message of the wonderful transmutability for both winemaker and wine drinker.
On June 15th, 2011 at 9:08 pm ,John wrote:
Great post. Thanks for sharing.
For years I’ve held on to (and used) pre ’63 copper pennies for this very reason.
On June 17th, 2011 at 11:21 am ,Kimberly wrote:
OK, so it’s not good then. Just last week we got an Australian Riesling into the wine store where I work, and it did definitely have that petrol smell. Which I’d often read about but never experienced. I was actually kind of thrilled to detect it though, because I was finally able to experience this thing I’d only been reading about up to that point.
Interesting.
On June 17th, 2011 at 12:45 pm ,Wine Cellar Roundup – Episode #39 wrote:
[…] had to include this write-up about petrol aroma’s in Rieslings. I really adore Rieslings, probably because they are so sweet. If you, like my husband, has the […]
On June 20th, 2011 at 2:54 am ,Dan Berger wrote:
What’s wrong with TDN? I use it all the time.
On July 2nd, 2011 at 4:49 pm ,Christian Jessen wrote:
Most of what has been writen here is correct. Actually in the Viticultural School I visited we had a term for Riesling ripening to early. This is called UTA – for “Untypischer Alterungston” – or “Untypical Ripening Aroma”. It appears in White Wines less than 2 years old … Sometimes it smells a bit of wet rag or mothballs (Naphtaline.) Originally, it used to be found in white wines from the Mediterannean Region. Whether it is do to 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) or any other chemical, most scientist today agree that it is a result of too much stress in the plant.
This has nothing to do with the petrol-tone a white wine – especially Riesling – will acquire do to the ripening effect of alcohol esterifying back to athenal/acetaldehyde, after 4 to 8 years depending upon other factors like sulphur-content or extract …
So … it would be too simple to try to explain it as just “Petrol Tone” …. There are a number of criteria to determine, whether or not the white wine should have such a tone and with what age …
On July 6th, 2011 at 4:38 am ,Riesling and petrol: right or wrong? wrote:
[…] Chapoutier was Oliver Humbrecht, winemaker at leading Alsatian producer Zind-Humbrecht. Humbrecht was reported as saying in New York last month that the petroleum aromas found in young Rieslings are unattractive and […]