Replacing wine's oldest guardian. Inside the search for sulfite-free wine.

Why winemakers reach for sulfites

Jamie begins with the basics. Burning sulfur produces sulfur dioxide, an extremely effective preservative that winemakers add for two main reasons: it stops unwanted microbes and it protects wine from oxidation, keeping it clean and fresh. Natural winemakers would rather add nothing, and some health-conscious drinkers want less, so the question is whether wine can be made without it.

Jamie notes that sulfites are the only ingredient most wine labels list, which helps explain why they attract so much attention. His plan is to hear from both sides: a winemaker who is already cutting back in a very traditional setting, and scientists developing new ways to protect wine. The result is a balanced look at a topic that often generates more heat than light.

Kloster Eberbach: 900 years of wine

The first stop is Kloster Eberbach, a former monastery in the Rheingau, now state-owned, with around 200 hectares of vines. Its winemaker shows Jamie the old hospital cellar, where wine was once part of the medicine, and explains that the monks probably worked with little or no sulfur. Sulfur use developed over the centuries because it keeps wine fresher and younger.

In the walled Steinberg vineyard, where winemaking began in the 12th century, she explains how the estate already avoids adding sulfites to the grapes. Because the press house is close by, healthy fruit reaches the winery fast, and tannins or non-fermenting yeasts can help hold back unwanted microbes. Sulfur is added only after fermentation and before bottling. She also shares early impressions of a trial with the 2022 vintage comparing sulfur with a tannin-based approach.

The science at Geisenheim

At Geisenheim University, a researcher studying alternatives to sulfur dioxide walks Jamie through how it is used: as liquid, tablets or powder, added to the must, after fermentation and before bottling. He explains its role against spoilage microbes and against laccase, an enzyme that oxidizes must from rotten grapes. He also points out that foods such as dried fruit, cheese and some meats often contain far more sulfites than wine, and that only a small share of people are sensitive.

Jamie and the researcher also discuss why regulators have not simply cut permitted levels across the food supply: shorter shelf lives could create bigger food-safety problems than the ones they solve. Still, there is real consumer demand for wine with no added sulfites, and that is driving a lot of research.

Two ways to go without

The first alternative is technical. Jamie sees a system designed to make wine with no oxygen at all, from grape reception through fermentation, sealed barrels and bottling, with sensors measuring tiny amounts of oxygen. In theory, keeping oxygen out removes the need for sulfites, and Jamie tastes a sparkling Riesling made this way.

The second is a plant-based preservative, a blend of phenolic compounds from 11 plants, designed to protect against oxidation and microbes and to replace sulfur completely. Only a small dose is needed. Jamie compares a young wine treated with it against one made with sulfur, and the conversation turns to an intriguing idea: perhaps what we think of as a wine's true taste is partly shaped by sulfites. The researcher admits that how such wines age is still an open question.

The test of time

To finish, Jamie returns to Kloster Eberbach, home to a collection of more than 10,000 old bottles, the oldest from 1773. There he tastes a 30-year-old wine preserved with sulfites and considers what might be lost without them.

Can we really eliminate sulfites from winemaking? Watch the episode to weigh the evidence with Jamie and hear his final verdict.

Go furtherTo explore the estates, vineyards and wines of the Rheingau and Germany further, the wein.plus wine guide is a great resource.