Winophilia

“Natural winemaking” is an issue of great interest these days to many consumers, not least because many wine journalists, retailers and sommeliers are touting its benefits. But they also may be tolerating  wine flaws that might have been prevented by judicious use of sulfur dioxide. What do YOU view as the most important role of sulfur products in the winemaking and aging process—IF there is one?

Larry McKenna, Escarpment Vineyards (Martinborough, New Zealand). Sulfur is imperative for the control of oxidation and the long-term  viability of any wine. Juices can be handled successfully without it but wines which are to be bottled require low levels of free sulfur dioxide. Wines without sulfur which do not need to age or travel can be enjoyable but have very short life spans (days). I’m very much in favor of local wines in local cafes which are renewed on a daily basis, but with anything beyond this time frame, the wines will be suffering from oxidation and premature aging.

Chris Figgins, Leonetti Cellars (Walla Walla, Washington). My view on the subject is one of judicious restraint. Is it possible to make good wines without the use of sulfur? Certainly. Is it possible to make great wines without the use of sulfur? Probably. Is it possible to make great wines consistently that will age and support an economically viable winery? In my opinion, that’s doubtful in this age. More and more, the consumer expects—as he or she ought to—that wines at all price points will be free of chemical (i.e., TCA), bacteriological (brettanomyces or aldehydes), and technical (oxidized) defects.

I view the single greatest role of sulfur in our wines as protecting against bacteriological defect. Our red wines here in Walla Walla are typically very high in total phenols and tannins. This allows us great freedom in not worrying about using sulfur purely as an antioxidant, as the wines have inherently high antioxidant capacity on their own. We further limit our use of sulfur through meticulous sanitation throughout the winemaking process and aging. However, even despite these measures, I prefer to use limited sulfur to protect against any bacterial infection (and their dreaded aromatic effects) in an effort to best preserve the aromatics and terroir of our vineyards. We have also proven that the industry “norms” are indeed many fold higher than necessary for stability. Overall, I guess you can call me a moderate on the subject! I suppose that opinions will vary widely by region as each has its own varietal peculiarities.

Chester Osborn, d’Arenberg (McLaren Vale, Australia). It is possible to make wine without SO2, but the risks go up enormously. Spoilage yeasts and bacteria are the biggest problems. Oxidation also will be advanced. No biggy if it’s going to be drunk really young. Some yeasts can produce lots of SO2 but not much of it will be free, which is the important part. Still does help, though. If you aren’t allergic to SO2, you’re better off drinking wine with it.

Great wine is (1) of a high quality and (2) ages well. With low or no SO2 the latter is very difficult to achieve and often the first is as well. (And of course there’s a third factor: clever marketing).

Marc Hugel, Hugel et Fils (Alsace, France). All the enology books say the same things. Sulfur products have a double action: antioxydant and antiseptic. That being said, the reality is a little bit more subtle. As long as you want to produce a classic wine that represents the style that has always been made in your wine area, the choice is not so broad. My experiences have shown me that each type of wine—depending on the variety, the vintage, the maturity, the level of noble rot, etc.—needs a very particular and precise level of sulfur, which is not always so easy to guess, especially at the fermentation stage. Any error in the choice—especially at the lower end—has an immediate and definitive consequence on the behavior of the wine: on its finesse, precision, structure, and expression of origin and terroir, and of course on the very important process of evolution in the bottle.

Being essentially a white wine producer, I believe that these considerations are especially accurate for this type of wine, but a red wine producer might have a different opinion.

Roberto de la Mota, Mendel Wines (Argentina). The use of SO2 in winemaking and viticulture is really old. In viticulture this activity is considered “organic.” In viticulture sulfur is used to control fungus infections like oidium or powder mildew. The sulfur applied in micronized powder is transformed into SO2 gas on leaves and controls this fungus. The application must take into consideration the temperature, because if it is too high then it could burn the grapes or the leaves.

In winemaking, SO2 has been used since ancient times as a bactericide, against bacteria like acetic, which produces vinegar, or as an antioxidant (applied by gas or powder as a potassium metabisulfite). When the quantity of SO2 is too high in wines, some people can suffer headaches or even digestive problems.

In general, white wines have more SO2 than reds and sweet wines much more than dry ones. (Low pH, acidity, alcohol and tannins help to protect wines against bacteria and oxidation). In very dry and healthy climates we can reduce the SO2 to practically nothing in vinification and to very small quantities in aging. This is not the case in humid and rainy conditions, where botrytis appears.

Another important use of sulfur was, and continues to be, in barrel maintenance. When we use new barrels we clean them only with cold water, but after we rack the wine, we often burn a pill of two grams of sulfur, producing SO2 gas that disinfects the barrel. The quantity of SO2 passing to the wine afterwards would be practically nothing.

It is important to know that before the use of SO2—in the 18th and early 19th century—in many places people protected their wine by heating or boiling it, to concentrate it for conservation, and later diluted it with water when they were ready to drink it.

Actually, with new techniques, materials, healthy grapes and very clean wineries, we can reduce the SO2 usage to the minimum or sometimes eliminate it entirely. Legal limits vary according to the country, but in general are around 100 ppm or milligrams per liter expressed in terms of total SO2 (i.e., free sulfur + combined). We can offer wines with less than half of this quantity. It’s important to say that all wines have SO2 after fermentation (20 to 30 milligrams per liter), because the vines absorb sulfates from the soils and then pass them to the grapes, and during fermentation the yeasts transform them into sulfites and after that into SO2 in the wines. (Some yeasts produce more than others).

Finally, we can say that the practice of using SO2 is far from being abandoned. We want to reduce it to a minimum under good and healthy conditions but not under other circumstances. We must research and find better ways. In the end, is SO2 used in very limited quantities as bad as some people think or say it is? Do those same people know how much sulfites some dried fruits like plums, apricots or raisins contain?

Bernard Hervet, Domaine Faiveley (Burgundy, France). Wine is a human creation, which doesn’t exist naturally. If you take some grapes and press them, you will get, at most, vinegar. Preservatives have been used for centuries to produce wines, spices, resins, alcohols. Sulfur happens to have many effects on wine and enables makers to fight against most of the possible risks (oxidation, plant and grape diseases, etc.) It’s easy to use and its effect on the wine’s acidity when added in small doses (20 milligrams per liter—i.e., 0.02%) makes sulfur an absolute most. Of course, the use of preservatives in the food industry is widespread (such as E202, or potassium sorbate).

Nowadays, wines cross continents and oceans to be drunk. Sulfur dioxide enables wines to maintain their organoleptic qualities from the winery to the customer. It also enables wine producers to highlight the quality of their soil composition by being able to offer, from one year to the next, wines whose organoleptic features consistently reflect their plot of land. Without the use of sulfur dioxide, the reality of the soil can be totally erased, as changes from one vintage to the next cannot be controlled.