Expert Roger C. Bohmrich, MW recently replied to another question stating that "Sulfites at low concentration also occur as a by product of fermentation of grape juice into wine." However, he also mentioned that some wines are sulfite-free. How can both of these statements be true? If this is correct, how are sulfites removed from these sulfrite-free wines? Lastly, how well do sulfite-free wines, or even those with no sulfites added, age as compared to "normal" wines that do contain sulfites added as antioxidizing or antimicrobial agents? Thank you!
Answer From Expert Roger Bohmrich MW
This is indeed a conundrum! The explanation lies with the tolerance that government regulations allow for the presence of sulfites in wine. This is not an unusual practice since, with many regulated products, producers are allowed varying degrees of leeway. Sulfites are a by product of fermentation, but the statement on the label that the wine "contains sulfites" is mandatory only if the level is 10 ppm or more. Wines which claim to be "100% Organic" are not permitted to use sulfites in the production process but may still contain trace and/or undetectable amounts, which on a practical level means they are sulfite-free. If the maker wishes to market such wines without the sulfite declaration, they must submit the wine to laboratory analysis to prove that the level is less than 10 ppm. The absence of added sulfites, or an extremely low level, implies that the wine must be handled with care as it may well be more sensitive to changes in temperature and light during shipping and storage. The winemakers who follow this approach tend to be artisanal and prefer a so-called "natural" approach, producing wine in very small volumes by hand, and some do not fine (clarify) or filter the wine before bottling. Since bacteria and yeasts may remain, there is a greater risk of spoilage once the wine leaves the protected environment of the winery. It is very difficult to gauge exactly how wines with no added sulfites age over many years in bottle, because there are so few of such wines and they are often types intended to be consumed young.
