Sourdough

Sourdough is bread raised by a culture of wild yeasts and lactic acid bacteria that you keep alive in a jar, rather than by a sachet of commercial yeast. The culture ferments the dough slowly, which produces the flavour and the keeping quality, and slowly is the operative word: a loaf takes most of a day and much of that day is waiting.

The reason a hobby this well documented defeats so many people is that the recipe is the part that does not vary. Flour, water, salt and starter, in proportions that barely differ between good bakers. What varies is your starter, your flour, your kitchen temperature and your schedule — and those four determine the loaf far more than any ingredient list does. A recipe that says "prove for four hours" is describing somebody else’s kitchen at somebody else’s time of year.

So the craft is reading dough rather than following steps, and the single most useful thing a beginner can learn is what an adequately fermented dough looks and feels like. Everything else on this page is in service of that.

What actually varies

Starter, flour, temperature, time

The hidden variable

Your kitchen temperature

The skill

Reading the dough, not timing it

What it costs

Flour, and a week of feeding a jar

1. 1

   Step 1: Get a starter rather than making one

   Making one from scratch takes a week or two and is a genuinely interesting thing to do once. Being given a mature one takes five minutes and removes the commonest early failure, which is trying to bake with a culture that is not strong yet. Bakeries, baking groups and neighbours give them away constantly.

   You will know it worked when: A culture that can actually raise a loaf.

2. 2

   Step 2: Feed it and watch it, before baking anything

   Feed it, mark the level on the jar, and see how long it takes to peak and start falling. That single observation tells you more than any recipe: it is how you learn what your culture does at your kitchen temperature, and the answer is what every schedule afterwards is built on.

   You will know it worked when: You know your own starter’s timetable.

3. 3

   Step 3: Buy a scale and weigh everything

   Including the water. This craft is worked in percentages of flour weight and cup measurements make it unreproducible, which means a failure teaches you nothing because you cannot repeat the conditions.

   You will know it worked when: Results you can actually compare.

4. 4

   Step 4: Bake one plain white loaf, and repeat it

   The same flour, the same quantities, the same method, several times. Changing one variable at a time is the whole method here, and the commonest beginner mistake is changing four — new flour, higher hydration, longer prove, different shaping — and learning nothing from the result.

   You will know it worked when: A baseline you can reason from.

5. 5

   Step 5: Take the temperature of your dough and your room

   A cheap probe thermometer. Fermentation roughly doubles in speed for every few degrees, which is why the same recipe takes four hours in August and eight in February, and why "prove until doubled" is better advice than any clock time.

   You will know it worked when: The variable behind most failures becomes visible.

6. 6

   Step 6: Put it in the fridge overnight

   Retarding the final prove in the fridge improves flavour, makes the dough far easier to handle and score, and — most usefully for a hobbyist — decouples the bake from the mixing so the schedule fits a working day.

   You will know it worked when: Better bread and a schedule you can live with.

Four things determine a sourdough loaf and all four are observable. Understanding what each is doing turns a recipe from an instruction into a description.

• The starter — A stable community of wild yeast and lactic acid bacteria. The yeast makes gas and lifts the loaf; the bacteria make acid and flavour. A starter used at its peak — risen, domed, smelling of yogurt rather than acetone — leavens strongly; one used after it has collapsed is weaker and more sour, which is a legitimate choice rather than a fault.
• Hydration — Water as a percentage of flour weight. Higher hydration gives a more open crumb and much harder handling; lower is easier and tighter. Beginners are routinely pushed towards high hydration by photographs and it is the wrong place to start — a moderate dough that you can shape teaches more than a slack one you cannot.
• Bulk fermentation — The long rise after mixing, and where the loaf is actually decided. What you are watching for is a dough that has grown noticeably, feels alive and domed rather than slack, and shows some bubbles at the edges. Under-fermenting is the commonest fault by a wide margin and it produces a dense loaf that people usually blame on the starter.
• Strength, built by folding — A set of stretch-and-folds spread across the bulk rather than a knead. Each one aligns the gluten and traps gas, and you can feel the dough change from sloppy to cohesive across three or four of them. This is the part that most rewards touching the dough rather than reading about it.
• Shaping and tension — A shaped loaf holds its form because the outer surface is under tension. A loaf that spreads flat in the oven has usually either been over-fermented or shaped without tension, and telling those two apart is a real diagnostic skill.
• Steam and heat — Bread rises in the first ten minutes of the bake, and it can only do that while the crust stays soft. Trapping steam — a lidded pot, a covered tray — is what allows that, and it is the single largest difference between a home loaf and a disappointing one.

• A digital scale — The one genuinely non-optional purchase. £10–£20, and it is what makes a result repeatable.
• Something that traps steam — A cast-iron Dutch oven at £30–£70 is the item that most improves a home loaf. A deep tray with an inverted roasting tin over it does the same thing for nothing, and is considerably easier to lift.
• A dough scraper — Three pounds, and it makes wet dough handleable in a way nothing else does.
• A jar for the starter — Any jar. A loose lid rather than a sealed one, because it produces gas.
• A probe thermometer — Cheap, and it makes the invisible variable visible. Worth more than any accessory on this list beyond the scale.
• A banneton, optionally — Nice, and a bowl lined with a well-floured tea towel does the job. £8–£15 if you want one.
• A lame, or a razor blade, or a sharp knife — For scoring. The specialist tool is pleasant and the sharpness is what matters.

• Reading the dough — Knowing when bulk is done by looking and feeling rather than by a clock. The first wall and the one that fixes most failures at once.
• Shaping — Building tension consistently. Improves quickly with repetition and is very hard to learn from words, which is why watching somebody do it once is worth an evening of reading.
• Managing the schedule — Bending fermentation around a working week with the fridge. The skill that turns an occasional weekend project into a habit.
• Adjusting for flour and season — Knowing that a new bag behaves differently, and that February is not August. The point at which recipes stop being necessary.
• Deliberate flavour — Choosing how sour, how open, how dark, and getting it on purpose rather than by accident.

• Wholemeal and rye — Different flours behave differently — they ferment faster, absorb more water and build less gluten. Rye in particular is a distinct craft rather than a substitution, and it is where a lot of people find the bread they actually wanted.
• High hydration and open crumb — The photogenic end, and the hardest handling. Worth pursuing once shaping is reliable and not before.
• Enriched doughs — Butter, eggs, sugar and milk. Slower fermentation, softer results, and the route to buns, brioche-style loaves and panettone — which is the marathon of the hobby.
• Sourdough beyond bread — Pizza, crumpets, crackers, pancakes and waffles from the discard. The practical answer to the guilt about throwing starter away, and genuinely good in its own right.
• Baking in quantity — A different discipline again — scheduling, batching, and the point at which people start thinking about a market stall. Note that selling food brings registration and hygiene requirements, which is a different regime from baking at home.

A starter is a colony you keep, feed and can kill by neglect, and the culture around it is unlike anything else in home baking. People name them. People take them on holiday, or leave feeding instructions with a neighbour. People post them, dried, in envelopes. It is faintly ridiculous and it is also the mechanism by which the hobby propagates — almost nobody’s first starter is one they made from scratch.

• Asking for starter is normal; being given it is the norm — Bakers give starter away freely and are pleased to be asked, because a discard that would have gone in the bin instead becomes somebody’s bread. If you are given some, the etiquette is to feed it, use it, and report back — the giver genuinely wants to know how it went.
• Nobody’s starter is better than yours after a few months — The most useful thing to know and the most persistently ignored. A starter you were given from a famous bakery becomes, within weeks, a colony adapted to your flour, your water and your kitchen temperature. Provenance stories are enjoyable and mean very little; the hundred-year-old family starter is mostly a hundred-year-old family story.
• Discard guilt is real and the community has answers — Throwing away half a jar of flour twice a day offends people, and there is an entire genre of discard recipes — crackers, pancakes, waffles — that exists to resolve it. So does keeping a smaller starter, which is the actual answer and is mentioned less often.
• Photographs of the crumb are the currency, and they mislead — An open, holey crumb photographs beautifully and is not the same thing as good bread — it is a specific style, it makes butter fall through, and chasing it is the commonest way for a new baker to become miserable. Experienced bakers say this constantly and it never quite lands.
• The word "sourdough" is not protected in the UK — Which is why the community cares about it. Bread sold as sourdough may legally contain commercial yeast and additives, a practice bakers call sourfaux, and the campaign for an honest definition is one of the few things the hobby is collectively political about.
• Advice is given in ranges, not numbers — A convention that takes new bakers a while to trust. Nobody good will tell you to bulk ferment for four hours, because their kitchen is not yours; they will tell you what the dough should look and feel like. Learning to read dough rather than a clock is the whole skill, and the culture protects it by refusing to give you the shortcut.