On every tour a guest eventually turns a bottle round, reads the back label and asks about the two words there: contains sulphites. It happens most often at a lunch table in Villié-Morgon, in Beaujolais, France, where one cellar bottles the same wine with and without added sulfur, and both bottles can carry the same warning. That pair is the whole subject in miniature.
I pour natural and classic wines at the same tables, from Georgia to Austria, and belong to neither camp. Sulfur is where the two camps argue hardest, and where most of what guests have heard is half right. This is the other half.
What sulfur dioxide does in a bottle#
Sulfites is the label word; the substance is sulfur dioxide, SO2, added as a gas, a solution, or most often as potassium metabisulfite, a powder that releases it. Winemakers have used it for several hundred years, first by burning sulfur wicks in empty casks to clean them, later by measuring it into the wine itself.
It does two jobs. As an antioxidant it binds the oxygen and the acetaldehyde that would otherwise turn a fresh white flat, dull and brown. As an antimicrobial it holds back the bacteria and stray yeasts that bring vinegar notes, refermentation in the bottle, or the barnyard smell of Brettanomyces. For a sweet wine, that second job is the difference between a stable bottle and a fizzing one.
How well it works depends on the wine’s own chemistry. Only a fraction of the sulfur in a wine is free and active, and how much of that is in the useful molecular form depends on pH: a high-acid wine needs less sulfur to be protected than a soft, ripe one. That single fact explains much of what follows.
Every wine contains sulfites#
Yeast make sulfur dioxide during fermentation, typically around 10 mg/l and sometimes several times that, with nobody adding anything. This is why sulfite-free wine does not exist and why the honest phrase is “no added sulfites”. In the European Union any wine above 10 mg/l total must carry the words “contains sulphites”; the United States uses the same threshold. Most wines cross it on their own, including many made with nothing added. The warning says the wine is not sulfite-free, nothing more.
Which brings us back to Morgon. At Domaine Marcel Lapierre the Morgon is bottled two ways: one lot with no sulfur added, marked with a small N on the label, and one given a small dose at bottling. Same vines, same vats, one decision made differently. It is the cleanest lesson in the subject I know; the house itself is in the Lapierre family in Morgon.
The numbers, honestly#
Legal ceilings first. In the EU a dry red may carry up to 150 mg/l total sulfur dioxide and a dry white or rosé up to 200 mg/l; sweet wines are allowed more, because sugar needs guarding. EU organic wine, regulated since 2012, is capped at 100 mg/l for dry reds and 150 mg/l for dry whites. The natural wine charters sit far below all of that: the French Vin Méthode Nature label, recognised in 2020, allows either no added sulfites or under 30 mg/l total, and other associations and fairs typically cap totals between 30 and 70 mg/l.
What is actually in the bottle is usually well under the ceiling. Many conventional dry wines finish between 50 and 120 mg/l total; a careful low-intervention producer who adds a little at bottling often lands at 20 to 40 mg/l; a wine with nothing added typically sits below 20 mg/l. For scale, the EU permits up to 2,000 mg/kg of sulfites in dried apricots, ten times the ceiling for a dry white wine. A handful of apricots from the health-food shop outdoes a bottle of Riesling.
One more distinction, because guests mix the two up. The yellow dust sprayed on vines against powdery mildew is elemental sulfur, a fungicide permitted in organic and biodynamic farming, and has nothing to do with the sulfur dioxide measured in the cellar. A grower can dust the vines in July and add nothing in October.
Headaches, asthma and who really reacts#
Sulfites get blamed for the red wine headache, and the evidence is thin. Dry reds carry less sulfur than most whites and far less than a sweet wine or a bag of dried fruit, neither of which has a reputation for headaches. The people who genuinely react to sulfites are a small minority, mostly with asthma, and the reaction is in the airways, wheezing and tightness, sometimes hives, not a throbbing head the next morning. For that group the label matters and a no-added wine is a real relief.
The more plausible causes of a rough morning are alcohol itself, dehydration, the amount drunk, and compounds that reds carry in higher concentrations than whites: histamine, tyramine, pigments and tannins that some people tolerate badly. Which of these matters most is still being researched. I am a sommelier, not a doctor; if wine reliably makes you ill, talk to one, and meanwhile drink water alongside.
Making wine with little or none#
Leaving sulfur out means doing everything else well enough that the wine protects itself. The list is the same in every cellar I know that manages it.
Clean, healthy fruit, sorted by hand, because rot and split berries bring the bacteria sulfur would otherwise kill. Acidity, from cool sites or early picking. A cold cellar: at Lapierre the grapes go into the vat whole and ferment slowly under their own carbon dioxide, the method Marcel Lapierre worked out with the chemist and négociant Jules Chauvet from 1981 onwards. Wine left on its lees, which consume oxygen. Few rackings, no filtration to strip out what protects it. And time.
Time was Stanko Radikon’s answer in Oslavia, in the Collio hills of Friuli. The estate’s whites ferment on their skins in open Slavonian oak vats and then spend years in large old botti, on the argument that a wine given long enough stabilises itself and needs little or no chemistry at the end. He and Edi Kante went further: from the 2002 vintage they used 500 ml and one-litre bottles with a slim custom cork, so the ratio of neck to wine ages the way a magnum does. That story is in Radikon in Oslavia; the hills are in my guide to Friuli and the Collio.
Skin contact helps too. The tannins and phenolics a white picks up from months on its skins are antioxidants in their own right, which is part of why a long-macerated amber wine tolerates very low sulfur better than a delicate white from a steel tank. It is how Ramaz Nikoladze, a few kilometres east of Kutaisi in Imereti, can bottle his Tsitska unfined, unfiltered and with no sulfur added, as I describe in Ramaz Nikoladze and the qvevri under the tree. The word qvevri on a label does not by itself mean no sulfur, though: Schuchmann’s Vinoterra wines in Kakheti ferment on their skins in qvevri, age in oak and are finished with a conventional sulfur regime, and I pour them gladly. Vessel and sulfur are two separate decisions.
How to taste the difference#
Too much sulfur has a smell: a struck match, a pricking at the nose, a wine that seems closed and faintly rubbery for its first minutes in the glass. Air clears it. Too little shows the opposite family of faults: bruised apple and sherry notes from acetaldehyde, the nail-varnish lift of volatile acidity, a prickle of gas from refermentation, or the one I watch for most, mousiness, a flavour like stale cracker that you cannot smell but taste at the back of the mouth a few seconds after swallowing. Not everyone perceives it. If you do, you will not forget it.
Between those extremes sits most of what I pour. My favourite exercise on tour is the Morgon pair from Lapierre, side by side. The unsulfured lot is usually the more perfumed and the more fragile; the sulfured lot a touch firmer and quieter on the first day. Neither is the better wine. That is exactly the point.
What I pour, and how to carry it home#
On the Jura and Beaujolais route we spend an afternoon in Morgon and Brouilly; my Beaujolais guide explains how the region became the movement’s home. On the Friuli and Collio orange wine tour the whites of Oslavia make the case for skins and time. On the Imereti and Racha tour you taste no-added-sulfur qvevri wine at a garden table and, later in the week, the same grapes made in steel under a conventional regime. I want you to have both in one trip.
Two practical notes. Wines with no added sulfur travel badly when warm, so buy them from a cool cellar, keep them below 15 °C on the way home, and open them within a few years unless the producer says otherwise. And read the label for what it is. Contains sulphites tells you almost nothing. The winemaker does. Ask.
For the wider argument, start with natural wine explained; for the vessel side of the story, qvevri, karas and amphora.
