subscribe: Posts | Comments      Facebook      Email Steve

Who let the cat out?


Pyrazine is an aromatic organic compound that can be synthesized by infusing phenacyl chloride — otherwise known as riot gas, which was used by American forces during the Vietnam War — with ammonia, another nasty smell. The molecule is widely found in vegetables; in various forms, it exists in bell peppers, asparagus and green peas. The smell of pyrazine is strong, and while humans have different thresholds, the amount required for sensory detection is relatively low. According to this analysis, “Imagine one single grape in 500,000 metric tonnes of grapes changing the smell of the entire batch. This is the strength of pyrazine.”

Few would tolerate the presence of pyrazine in red wines. Indeed, the main reason why Monterey County red wines were almost destroyed on the market a generation ago was because they reeked of pyrazine; the notorious “Monterey veggies” was a category killer for Monterey Cabernet Sauvignon, a problem that still plagues it. Question: if pyrazine is such an aggressively annoying smell in reds — and it is — why do we tolerate it in Sauvignon Blanc?

I ask the question because I have once again shocked some vintners who asked me to taste their pyrazine-heavy Sauv Blancs. They themselves love their wines, and can’t understand why I would give scores in the low 80s, sometimes even worse. Well, here’s the reason: I detest the smell of pyrazine in Sauvignon Blanc. To me the wines reek of unripeness. “Sauvignon Blanc grown under cool conditions tends to have higher levels of methoxypyrazines in their grapes than Sauvignon Blanc grown under hot conditions” (methoxypyrazines are one form of the compound), says this scholarly paper, published last year in Wine Business Monthly. And who likes unripe wine, red or white?

I don’t remember pyrazines being an issue for California Sauvignon Blanc before the advent of Marlborough Sauvignon Blanc in the 1990s. Those wines took the country by storm; people, including me, loved the racy acidity, and also the telltale taste of gooseberry. Maybe some Californians started picking earlier in hommage, I don’t know. Gooseberries are similar to currants, but they can be unripe also. A ripe gooseberry has a pleasant, Muscat-like penetrative scent (similar to the Musqué clone of Sauvignon Blanc), while an unripe gooseberry is like any other unripe fruit, i.e. disagreeable and sour, like a juniper berry. You can make good pies, puddings and cobblers with unripe gooseberries, but that’s because they’re sweetened with sugar.

We’re talking about an aroma/flavor spectrum here. Gooseberries are fine, if they’re ripe and fragrant. So is hay, new-mown grass and other “lifted” scents that characterize Sauvignon Blanc. And then, of course, there are good, old, familiar citrus fruits that also are pleasant and proper in the variety.

But the extreme end of that spectrum is pyrazine. Call it cat pee, tom cat, feline spray, litter box, what you will, it’s a most unattractive smell. Nor do I believe that pyrazine is a typical smell in Sauvignon Blanc, one that a critic should respect even though he might not personally like it. That’s not true — unless you insist that unripeness is typical of the variety.

A few days ago, I tasted a high-end Sauvignon Blanc from a well-known producer and I could not give it a good score because of the pyrazine. When I later saw the producer, he asked me what I thought, and I had to be honest, in a polite way. He seemed puzzled that I didn’t “get” his wine. I was puzzled also. Did he not smell and taste the same pyrazine as I did? And then, just this morning, I got a request from a Napa winery to retaste their Sauvignon Blanc, which I’d given an “81” because it was so pyrazine-y.

Maybe sensitivity to pyrazine runs in my family’s DNA. When I once gave my sister a pyrazine-heavy Sauvignon Blanc, she said the smell made her gag. Or maybe pyrazine is an acquired taste. If so, I have a long way to go before I can accept it.

This just in: My blog has been named one of the top 10 Beverage Blogs in the country!

  1. I’m sure that different people have different levels of sensitivity to compounds like pyrazine. I’ve tasted some expensive, high-end Napa Cabs recently that had too much for my tastes – and it drives me NUTS about many of the Chilean red wines on the market.

    I’ve got a similar issue with TCA – even small amounts drive me crazy, and it’s worse that those small amounts flood my sensory receptors, which means that I can’t smell TCA again for about another 15-20 mins.

    Bottom line is that this is one of drawbacks of a single-taster reviewing a wine. Of course, there are many advantages to that scenario as well (consistency being one).

  2. At least with a single taster, the consumer knows exactly where that person is coming from.

  3. Jamie Goode associates the cat pee smell with mercaptans as opposed to pyrazines (see the table at, though definitely pyrazines are a major factor in the herbaceous cat pee ‘style’ of Sauvignon Blanc. Interestingly, these same mercaptans are also associated with fruit aromas (currant, tropical fruit and probably gooseberry) according to Goode. I’m definitely curious as to how these compounds are connected as ripeness seems to determine where on the cat pee & herbaceous spectrum a SB is.

    I’m actually a big fan of pyrazines in reds. I don’t care for overwhelmingly vegetal flavors, but if a wine is treated gently, for me it can be a complexing aroma. In fact, if there is no bell pepper or jalapeno in a Cab, I find it boring and borderline flawed due to over-ripeness. That’s not to say I approve of weedy, herbal reds. I don’t. But it seems winemakers who don’t over-extract and have good fruit can often make pleasingly herbaceous smelling wines without turning it into a herbal tincture or cherry cough syrup on the palate.

    Then again, this is an acquired taste. Chilean reds, central coast Bdx blends and Loire reds were my first favorites . . . .

  4. Greg, interesting to compare your liking for some greenness in Cab with 1WineDude’s statement [below] that he’s tasted some Napa Cabs with too much green for his taste. Just shows how personal preference plays a part.

  5. Worked a couple vintages in NZ and spent a fair amount of time sorting hand picked Sauvignon. Visually there was almost no difference between the beautiful, ripe clusters and the green grass, kitty kat, Granny Smith clusters that usually were second set. A quick bite into a questionable cluster would knock you down with a screaming pyrazine laden punch. Pick early here , then it’s just green and weedy with out the ripe component. Love the racy, acid driven NZ Sauvignons, I can live without the cat.

  6. I don’t mind a hint of ‘green’ to keep things interesting in reds, but it depends on the red of course, and the amount of green…

  7. Steve, interesting to me that so far no mention of Sancerre has been made. To me those are the quintessential sauv blancs, and yes they have plenty of the “pipi du chat” (technical term) that you so detest. But there is a flavor spectrum there also. Some CA sauv blancs go too far into the cat pee universe, but that’s a sliding scale, and obviously you are at the high end of intolerance. I am the same way with brett and VA – two flaws that are often praised by other critics. It’s good to know your palate so well, and to make it clear to your readers where you stand. But I try to be a little more forgiving when rating wines that may not fit my personal taste, but have wide appeal to consumers.

  8. Steve, you’re right. Pyrazine is a symptom of under-ripened grapes; due to high yields, or to a climate where “some varietals cannot achieve enological ripeness”.
    Carménère has huge amounts of pyrazine too. Chilean scientists are desperately searching for a more economically viable clone, with lower levels of the compound.
    According to this paper by Kay Bogart and Linda Bisson from UC Davis, the best way to avoid the undesirable vegetal or herbaceous characters is to reach physiological ripeness via: a very delicate balance between canopy size/leaf area and quantity of fruit per vine; early season deficit irrigation; and lots of sunlight and dry weather between fruit set and veraison.

  9. Paul, interesting point you make about being forgiving, etc. I try to hedge my reviews with phrases like “May not be to everyone’s taste” or “some will like the strong, aggressive aromas,” and so on. Then I give my rating. People can tell by the score whether I personally liked the wine, but they can infer from the text that, while I might have given it a low score, I recognize that it does define a certain style that some people enjoy.

  10. Morton Leslie says:

    Veggie aromas and mercaptan aroma are close and sometimes hard to differentiate. I remember once three decades ago driving back from Monterey with a UCD professor after attending an ASE event. We fell into discussing the Monterey “problem” in Cabernet. It was our thoughts at the time that the worst emanations of the smell were more like mercaptan, than pyrazine. It was like the mercaptan smell of pee after eating asparagus. (His descriptor, not mine) Some of those early wines were pretty hard to stomach, but the ones that were more purely “pyrazine” could be tolerated if they were not intensely scented and the mouth aroma and taste were pleasiing. It is a similar thing for me and the “pyrazine” SB’s. If they aren’t intense, and don’t come back up to the olfactory when the wine is in the mouth, and the taste is refreshing and lingering, then I can toss them down. No problem.

    SB does have some interesting descriptors, most tasters know tomcat, but I wonder how many winetasters who describe a SB as gooseberry have ever smelled a fresh gooseberry? Most likely if American they’ve seen the green little North American gooseberries in pictures. In the southern hemisphere a Cape Gooseberry is a fruit that looks exactly like a tomatillo, is covered in a similar looking husk, but is orange in color and has an exotic tropical fruit aroma. I don’t know about others but that exotic aroma is the gooseberry behind my descriptor.

    One other thought. After a trip decades ago where I tasted a lot of fresh Bordeaux out of the barrel I was struck by the number that showed veg, yet later in the bottle, it had disappeared. That is when I discovered the benefits of air and quarterly barrel to barrel racking done in the classic fashion out of a bung in the barrel head with a nice splash. (Something no longer requred with wine made from raisins, and, in fact, not adviseable.) Air eventually worked its way into Monterey winemaking as winemakers found the oak barrel in lieu of big cooperage, and I think it helped.

  11. Steve, Paul. Morton–all interesting extensions of Steve’s central theme.

    –Steve. I don’t know if forgiving is the right word because it suggests benign neglect or something like that. And, I think what you probably practice is a recognition of the wider preferences of your audience. Perhaps I am projecting from my own experience, but I often praise, and score highly, wines that I think are very successful even when they do not suit my personal preferences for a place in my cellar. And I, and CGCW, have no problem saying so and recommending wines to a wider audience.

    Highly ripe Zinfandel, for sure, requires this wider cut and so do Petite Sirah tannins, and rich, ripe, oaky Chardonnays. I have no problem liking praising the Hobbs and Pahlmeyer styles while also praising the Freestone, Miramar, Bjornstad, Pfendler style.

    The question then pertains–where are the limits and all I can say about that is there are times when wines simply are too full of pyrazines or too high in acidity or too tannic without balancing fruit or too oaky or, or, or … that they simply do not get praised. Interestingly, I do get letters, and I would be you get them also, in which a subscriber will say, I do not often agree with your palate, but I can find the wines that suit me because of the words you write. It is this latter occurence which is ignored by folks who only see our writings as scores and refuse to recognize that a great deal of effort goes into our descriptions.

    Paul– I am with you on the need to write for the readers, not for some limited vision of perfection. Someone is no doubt going to challenge us on this point, but I think the ability to understand and describe wines for what they are and to understand that high quality is not limited to one model is what professional writing needs to be about. That does not make us apologists or cheerleaders, but it does reflect a broader understanding of the world.

    Morton–It helps that much of those early Monterey plantings were pulled out. No matter how you slice it, green is green is green and too many of the early Monterey reds were simply unpalatable regarding of anyone’s desire to be forgiving.

  12. Peter, I also like carménère–it’s the grape that thinks it’s a pepper! But it definitely seems to have problems finding that balance. I’ve read it often requires acid addition to bring it into balance when ripened to the point where veggie aromas and flavors aren’t monolithic. The combo of stewed fruit and veggies is an odd one to say the least! I’ve had a Lapostolle Carménère that seems to get it right, though: fresh fruit and all varieties of peppers.

    Morton, I’ve read that micro-ox (be it by barrel or by specialized tool) can be used to oxidize pyrazines, especially when a wine is young and can buffer against oxidation. Is there perhaps a connection between reductive, fruit-forward winemaking and the perceived need for ever riper fruit? It seems you’re suggesting less ripe fruit could be harvested if people used the right techniques in the cellar. I like this idea . . . .

  13. Charlie, all good points, and common sense. The only place I differ from you is that I don’t really have “personal preferences” when it comes to wine. I know that sounds bizarre. But I like any well-made wine. So it’s unlikely that I would pan a wine that was a good example of its type, just because I didn’t like it. If it’s a good example of its type, I will like it! And when I don’t like a wine, it’s not because I don’t understand its typicity, it’s because there’s something wrong with it. Readers who have followed me know that some things I consider flaws in dry table wines are residual sugar (I don’t mean a wine that’s supposed to have RS, I mean wines that aren’t), strong pyrazines, lopsided acidity (that tastes like it was poured out of a bag), bitter tannins (that don’t seem likely to help the wine to age), brett, and ugly ass oak.

  14. I think that I’m a bit similar to you, Steve, in that I don’t have strong personal preferences with regards to wine but do consider some things fairly serious flaws. That said, I’m a bit more tolerant of brett and pyrazines than some other things. I do think that a little bit of either can be interesting.

    I also realize that some people think that the smallest amount of either is horrible. For wines that have some brett but are still good in my opinion, I characterize the aromas in the review (barnyard, band aid). For pyrazines, I tend to give flat out warnings (ex. I recommend this wine because… but if you don’t like cat pee in SB, do not buy it.).

    I’m able to do this because the only person condensing my reviews is me and I don’t provide numerical scores. Were I to do so, I would probably treat pyrazines the way you do. In the end, there are plenty of beautiful Sauvignon Blancs out there that don’t have any at all.

  15. Greg, Carménère is, indeed, one of the toughest varieties to achieve balance. It needs a very long growing season with mild high-temperatures to preserve acidity; it also favors cold, heavy clay soils (Merlot -like), exactly like the ones found in the Apalta (Lapostolle, Montes…) region, to develop complexity.
    The drawback is that heavy soils promote plant growth and high yields, and delay physiological maturity; an issue for a late ripener, and pyrazine-loaded, variety like Carménère.

  16. Steve,

    Hard to believe that you don’t have a “personal preference” when you write “I detest the smell of pyrazine in Sauvignon Blanc.” Sounds pretty much like a personal preference to me–one that in the end you essentially state influences your scores.

  17. Michael, I meant that there are no wines I’ve ever had that I couldn’t appreciate, so long as they’re properly made, i.e. without flaws. I consider excessive cat pee in wine a flaw, not a characteristic of a varietal. That doesn’t mean if I were stranded on a desert island, there aren’t particular wines I would ask for. Champagne tops that list (provided I had a refrigerator). I probably would not want a 15.7% Zinfandel, but I can give very high scores to high alcohol Zins when they exemplify their style.

  18. Steve,
    I think you are confusing pyrazines, which have green pepper/asparagus kinds of flavors with volatile thiols, which include the dreaded cat urine aroma. Specifically, the compond 4-mercapto-4-methylpentan-2-one (4MMP) exhibits gooseberry, broom, and cat pee aromas in wine. Sauvignon blanc that is made using reductive techniques can show these aromas even when fully ripe.

  19. Tom, others have suggested mercaptans as the culprit. Whether its pyrazine, mercaptan, thiols or something else, cat pee is a turnoff for me!

  20. Steve,

    The typically accepted practice of reducing the “cat pee” smell in SB is leaf thinning in the vineyard. Traditionally it is thought that shaded clusters lead to those aromas. In well tended vineyards throughout July, you’ll see hands carefully pulling leaves for a dappled afternoon light. I agree, I’ve always hated the smell. Maybe more so now, because I know it comes from poor vineyard management.

  21. Scott, I wonder if some winemakers deliberately include this smell, either because they like it (?!?) or because they think some critics and consumers do. To me, it’s a complete turnoff.

Leave a Reply


Recent Comments

Recent Posts