What can be done about the fermentation defect causing your wine to smell sulfurous?
Have you ever taken a drink of something—say, let’s a lovely full-bodied Shiraz—and noticed that the aroma veered from earthy to downright revolting? Did the odor kind of smell like steamed cabbage to you? a lunch of broccoli from a coworker? Would it maybe have a faint…farty odor?
You’re not merely taking in smells. No matter what the person who sold you the wine says or what is printed on the back of the bottle, the wine isn’t “earthy” or just has “terroir.” The problem with that foul wine is something called “reduction.” (Read more about many typical wine defects here.
In the 10 years I’ve spent tasting and buying wine for restaurants and retail establishments, I’ve come to realize how few people are even aware that this issue even exists, much less know how to recognize or cure it. I chatted with a few experts in the wine industry to better understand what it is, the causes it, and how to fix it if you don’t have any wine accessories.
What Happens During Reduction?
The excellent and in-depth book Flawless: Identifying Faults in Wine by wine science specialist Jamie Goode states that “Reduction is the popular word for the presence of volatile sulfur compounds (VSCs) in wine.” It was explained more plainly by Eric Jensen, vigneron and winemaker for the Paso Robles, California-based Booker Wines and My Favorite Neighbor labels, both of which he founded. He exclaimed, “I would just call it nasty.” That is straightforward… It requires more oxygen if we consider it to be diminished.
Reduction, according to Faith Comas, a wine expert at Prestige-Ledroit Distribution Company, occurs “when there is a lack of oxygen throughout the fermentation process.”
Hence, if a wine smells like cabbage, farts, canned vegetables, or burnt rubber, it probably has too many volatile sulfur compounds, which are brought on by a lack of oxygen during the wine-making process. If you don’t like it, you’re not a simpleton; you’re spotting a genuine problem in the wine.
A few typical volatile sulfur compounds are to blame for the bad taste in your wine. Goode claims that whereas dimethyl sulfide smells like canned corn or cooked cabbage, hydrogen sulfide smells like rotting eggs or a drain that needs to be cleaned. The mercaptans are a nasty little group of scent chemicals that follow. If you believe that 3-Mercaptohexyl Acetate doesn’t seem too bad, you’re right. It smells strongly like grapefruit, passionfruit, and other citrus fruits. Many individuals enjoy these scents in specific wine varieties. Other mercaptans, such as ethyl mercaptan, which smells like burnt matches, and methyl mercaptan, which smells like burnt rubber and more of those amusing cabbage fragrances, provide less pleasant aromas.
Is there a rise in reduction?
Professionals in the industry disagree on whether reduction occurs more frequently now than it did in the past; some will say yes, and some will hesitatingly answer. In the last five years or so, I’ve personally seen more reductive wines when sampling them for retail purchase.
If you’re familiar with wine, you might wonder if the airtight seal offered by screwcap closures is to blame. Although they have been linked to reduction and may be the root of certain cases, Goode notes that studies haven’t shown a direct connection between the two. According to Comas, “nearly all of the bottles that have been decreased have been sealed with a cork,” in her experience.
A perceived overabundance of reduction in wines may be explained by the popularity of natural wine. In order to reduce the amount they add to or tinker with their product, many natural wine producers utilize little or no sulfur dioxide, a preservative. One of the functions of sulfur dioxide in the production of wine is to reduce undesirable odors and flavors brought on by oxidation, which is another word for “spoilage.” Are are aware of how overly lengthy exposure to air causes apple slices to become brown? In wine, a similar process known as enzymatic oxidation takes place. Oxidation could taint the wine if the wine-making process introduces oxygen either too early or too late.
Yet, one of the few alternatives a winemaker has if they choose not to utilize sulfur dioxide is to reduce the amount of air used in the process, which can result in decrease. Sales manager David Witkowsky of Maryland-based importer and distributor Potomac Selections believes that this is the reason why he has noticed more wine reduction recently than in the past. It’s become a tool, he claims, for winemakers who wish to use less sulfur because sulfur helps prevent unwelcome oxidation.
How to Use Reduced Wine
Now that we have a name for that stinky, cabbage-like wine, we also have a few theories as to where it might have originated. However, what should you do if you come upon one of these foul wines?
Every expert I spoke with agreed that oxygen is necessary for reducing wine, whether it is in a winery or on your kitchen table.
This is Jensen’s counsel: “Spray it all over. If you don’t have a decanter, just take a pitcher and splash it in there. “Let it fly!” Here’s another vintage Turrone trick: “If the issue is a straightforward sulfide, you might be able to put an old copper coin in the glass and watch as the odor mysteriously vanishes. Typically just a little time and air will allow you to see through to what the wine actually is, unless the issue is truly terrible. Some of the substances that create reductive aromas are changed by copper into solid materials that sink to the bottom of the container. I wouldn’t go dumping handfuls of pre-1982 pennies into every bottle you buy, though, as wine is acidic and can cause the metal to leach into your wine (pennies created before this period are 95% copper). Yet, all you could need to get rid of that stench is a pitcher and perhaps a copper penny. Wine accessory manufacturers, you’re fired!
If you order a wine at a restaurant and it smells diminished, let the server or sommelier know and request that it be decanted. At least portion of that reduction will have evaporated after around 20 minutes. Pouring the wine into your glass, giving it a vigorous swirl, and then waiting a few minutes will further hasten this process. If that doesn’t work, most restaurants with good wine lists will bring you something else and not charge you for the bad bottle, though this will depend on the restaurant’s policy as reduction isn’t always an obvious problem.
In the end, reduction is a matter of taste.
Certain faults, such as the 2,4,6-trichloroanisole (TCA) component that produces cork taint, are always detrimental. There is no room for doubt when wine gets corked: it’s always revolting.
Reduction is one of those gray-area defects, though, and for various people, it exits the gray and enters the stinky at different times. As Turrone explained to me, “Everyone’s threshold concentration is different, so there are diverse opinions of a wine that straddles the threshold line. This makes it much harder for the winemaker. Only a reduction that is fairly significant will be recognized by a casual wine drinker, yet they may enjoy or dislike a wine because of sulfides without fully understanding why. Sneaky, yes?
Further complicating issues is the fact that wines can gain aromatic complexity through reduction when used sparingly. Recall 3-Mercaptohexyl Acetate, our pal? Whether you enjoy the sharp, grapefruity flavor of Sauvignon White or the somewhat smokey, matchstick-like scent of some French Chardonnays, you’ve undoubtedly drunk wine that has been slightly lowered as a result of this chemical or one of its relatives. When it’s under control in these genres, it lends them their own personalities.
Yet, an excessive reduction can also result in a homogeneity that hides the distinctive qualities that give many grape varietals and wine styles their individuality. One more quote from David Witkowsky: “In both circumstances, I think it’s terrible since noteworthy reduction tastes and aromas have no sense of place. They are the same everywhere in the world—so if they become a dominant component in the wine, it obscures the wine’s individuality.”
Yet, not everyone like these artistic examples of reduction, so it’s okay if you don’t, either. According to Jensen, “There are many excellent winemakers who make very reduced wines; that’s their style. They have reasons for not wanting a lot of air. I believe their justifications are out of date and flawed chemically. He continues, “I’m not a reduction man… but those guys aren’t incorrect; it’s just different. Liking that style is a matter of taste.”
Hence, a little reduction might be beneficial, but too much reduction can ruin what should be a fantastic bottle of wine. A wine has to be extremely fantastic after the stench has worn off for me to have that type of patience, but drying out these stinky wines often fixes them.