Wine Wizard replies: It is impossible to make a sulfite-free wine, because wine yeast produce sulfur dioxide (SO2) during the fermentation process. Wines with no added sulfite contain from 6 to 40 ppm of sulfite, according to most experts. Furthermore, it’s likely that the concentrate in your Pinot kit already got a healthy dose of sulfur dioxide at the processing plant.
Before you toss out your kit, check with your physician to make sure that you really are allergic to sulfites. Only a small percentage of the population (approximately 0.01%) is truly allergic to sulfites. These people lack the digestive enzyme sulfite oxidase and therefore can’t metabolize sulfites. This small percentage of the population is also asthmatic, so many doctors test their patients for sulfite allergies when a diagnosis of asthma is made. These individuals typically know they’re allergic from childhood and so know to avoid all foods and beverages that contain sulfites including, but not limited to, lunchmeats, processed salami, processed fruit juices, packaged seafood and dried fruits, as well as wine.
Sulfur dioxide gets a bad rap because of the government warning label plastered on wine bottles that is only targeted to this select group of consumers. Furthermore, many people blame sulfites for the group of symptoms commonly called the “wine headache.” These symptoms are often simply caused by the alcohol in the product. There has been some speculation in the medical community that histamines — a naturally occurring substance found in foods like canned tuna and wine — are a possible culprit of this “red wine malaise,” but there has been no conclusive evidence so far. Ironically, many consumers drink white wine, thinking red wines have more sulfites, when actually white wines typically do.
If you want to lessen the amount of sulfites you use in your wine, keep the following things in mind. Sulfur dioxide is used for two reasons: its anti-microbial ability and its antioxidant capacity. Therefore, if you want to use less of it, minimize the amount of microbes and oxygen that contact your wine in every stage of its life. Cleaning and sanitizing effectively is one of the easiest ways to knock down populations of spoilage bugs. Make sure your incoming fruit, juice or concentrate is clean and free of visible mold or bacterial colonies before inoculation. Use a strongly-fermenting commercial yeast for your primary fermentation in order to out-compete spoilage organisms in the first few weeks of a wine’s life. Make sure your wines are fermented to dryness so there is no residual sugar left as a carbon source for spoilage bacteria. Gas your empty containers with carbon dioxide during transfers and rackings so that there is minimal contact with oxygen.
Natural wine components that inhibit organisms are alcohol and acid. High pH (low acid) wines are more prone to microbial attack, so keeping the pH lower than 3.5 will help retard infection. The lower the pH, the more unhappy most sorts of spoilage bacteria will be. Similarly, the higher the alcohol, the more unhappy the organisms. Alcohol levels over 14% can help to keep bugs at bay.
At the end of the day, using sulfites in winemaking is usually not a health issue. Judicious of sulfite use can significantly increase the quality of your wine. International regulatory boards usually set legal levels at around 350 ppm total sulfur dioxide and most commercial wines are bottled with totals between 50-100 ppm. A little bit of SO2, used wisely, goes a long way and won’t hurt 9,999 out of 10,000 of us.