Type "is sourdough gluten free" into Google and you'll get a confusing mix of answers — because the honest truth depends entirely on what the sourdough is made from. Ordinary sourdough made with wheat flour is not gluten free, and the long fermentation does not make it safe for coeliacs. Genuine gluten-free sourdough exists, but it has to be made with gluten-free flours and a gluten-free starter from the outset — there's no halfway version. Here's the honest, unambiguous answer, and how we make ours.
Is sourdough gluten free? The short answer
No — not if it's made the traditional way, with wheat flour. Sourdough is a method of raising bread using a wild-yeast starter and a long, slow fermentation, rather than commercial baker's yeast. The method changes how the bread rises and tastes. It does not change what the flour is made of. If the starter and the flour are wheat, the loaf contains gluten, full stop.
This matters more than it might seem, because "sourdough is easier to digest" and "sourdough is basically gluten free" are two of the most persistent myths in the gluten-free world — and they can genuinely catch people out.
Why fermentation doesn't make wheat sourdough safe for coeliacs
The idea that long fermentation "breaks down" gluten enough for coeliacs to eat wheat sourdough safely is a myth, and it's an important one to be clear about, because getting it wrong isn't a minor inconvenience — for someone with coeliac disease, it means real physical harm.
Coeliac disease is an autoimmune condition triggered by gluten — the protein found in wheat, barley and rye. Even a small amount can cause damage to the gut lining. Some traditional sourdough fermentation does modestly reduce certain gluten fractions over time, which is where the myth gets its foothold — but nowhere near enough to bring a wheat loaf down to a level that's safe for someone who needs to avoid gluten completely. A wheat sourdough loaf, however slowly fermented, however "traditional", is still a wheat loaf.
If you're coeliac, or baking for someone who is, the only safe rule is the boring one: check the flour, not the method.
What genuine gluten-free sourdough actually is
Real gluten-free sourdough is a different thing built the same way, just without the wheat. It starts with gluten-free flours from the very first stage, and — crucially — a gluten-free starter, cultivated and fed on gluten-free flour rather than a wheat one. From there, it follows the same sourdough principle as any other: wild yeasts do the raising, and a long, slow fermentation does the flavour and texture work that a quick commercial rise can't.
That's the bit worth remembering when you're checking a label or asking a bakery a question: gluten-free sourdough isn't "sourdough with the gluten taken out" — there's no taking it out once it's in. It's sourdough built from gluten-free ingredients from day one, starter included.
How we make ours at The Bakery by Knife & Fork
We're a 100% dedicated gluten-free bakery — a completely wheat-free site, so there's no cross-contamination to worry about. We bake for coeliacs first and foremost, and our sourdough is made from our own gluten-free starter, using wild yeasts and a proper long fermentation, exactly as described above. No shortcuts, no wheat starter "just for the culture", no additives or gums to fake the texture a slow ferment gives you naturally.
We use wholegrain gluten-free flours, and we bake fresh to order each week rather than holding stock — you can see the whole rhythm of how that works on our how it works page. The slow way pays off: we're currently rated 4.79 stars from over 1,400 reviews (and our Rosemary Focaccia picked up a Great Taste Award along the way) — the fermentation does real work on flavour, not just marketing copy.
If you want to see (and taste) the difference a proper gluten-free starter makes, our sourdough loaves are all in the gluten-free sourdough collection. But if you're new to us, the easiest way in is the Taster Bundle — a low-commitment way to try a proper loaf before you settle on favourites. And if gluten-free sourdough turns out to be a regular fixture in your kitchen (it tends to be, once people find bread that actually tastes like something), Build A Box lets you put together your own mix on a rhythm that suits you — weekly, every two weeks, or monthly — with 5% off every box and guaranteed loaves even in weeks we sell out.
Frequently asked questions
Can coeliacs eat sourdough bread?
Only if it's made entirely with gluten-free flour and a gluten-free starter. Sourdough made with wheat — however long it's fermented — still contains gluten and is not safe for coeliacs. Always check what the flour and starter are made from, not just how the bread was raised.
Does the fermentation process remove gluten from wheat sourdough?
No. Fermentation changes flavour, texture and how the bread rises — it doesn't remove the gluten protein down to a safe level for coeliacs. Genuine gluten-free sourdough has to start gluten free, starter included.
Is all sourdough gluten free?
No — this is one of the most common myths around gluten-free eating. Whether a sourdough loaf is gluten free depends entirely on the flour and starter it's made from, not on the fact that it's "sourdough".
How is The Bakery by Knife & Fork's sourdough made?
From our own gluten-free starter, with wild yeasts and a long fermentation, using wholegrain gluten-free flours and no additives or gums. We're a 100% dedicated gluten-free bakery, so there's never any wheat flour on site to worry about. You can read more on our FAQ page.