Sourdough in a Cold Kitchen: Winter Baking Adjustments

 

Winter changes sourdough more than any other season. The same recipe that rose in four hours in August can take eight hours in January, or stall completely, and the starter that doubled reliably on the counter suddenly looks sluggish and flat. Nothing is wrong with your baking. The yeast and bacteria in your starter are simply cold, and cold microbes work slowly. Once you adjust for temperature, winter baking becomes predictable again, and it can even give you better flavour, because slow fermentation is where sourdough flavour comes from.

The short answer

To bake sourdough in a cold kitchen, use warmer water so the dough itself starts warm, aim for a dough temperature of 75 to 78 degrees Fahrenheit (24 to 26 degrees Celsius) after mixing, and give the dough more time, roughly 1.5 to 2 times the warm-weather bulk time. Keep the dough in the warmest spot you can find, feed your starter with warm water and give it extra time to peak, and judge readiness by how the dough looks and feels, not by the clock. Do not try to fix a cold kitchen by adding more starter, and do not put the dough somewhere hot. Gentle, steady warmth beats a blast of heat every time. This article is about baking in a cold room. It is different from cold-proofing in the fridge, which is a deliberate technique where shaped dough goes into the refrigerator. A cold kitchen is an accident of the season. The fixes are different, and mixing them up causes confusion.

Why cold slows everything down

Sourdough fermentation is driven by temperature. Yeast produces gas, bacteria produce acids, and both work faster when warm and slower when cold. The relationship is not gentle. A drop of 10 degrees Fahrenheit (about 5 degrees Celsius) in dough temperature can easily add hours to bulk fermentation. That is why a recipe that says "bulk ferment for 4 hours" is only true at the temperature the recipe writer had in their kitchen. At 65 degrees Fahrenheit (18 degrees Celsius), the same dough might need 7 to 9 hours. At 60 degrees Fahrenheit (15 degrees Celsius), it might need overnight, and the starter might barely move at all.

The starter suffers first, because it is a small amount of culture in a cold jar. A starter that lives on the counter in summer can go almost dormant in a cold kitchen in winter, especially if it is fed with cold water and cold flour straight from a chilly pantry. The fix is not to feed it more often. It is to feed it warm and give it time. If you are still learning your starter's habits, our feeding guide covers ratios and schedules, and our troubleshooting guide covers the cases where cold is only part of the problem.

Start with dough temperature, not room temperature

The single most useful habit in winter baking is measuring dough temperature. Room temperature is a poor guide, because flour from a cold pantry, a cold bowl, and cold water can pull a dough 10 degrees below room temperature before fermentation even starts. An inexpensive instant-read thermometer, the same one you use to check a finished loaf, is all you need. After mixing, the dough should read 75 to 78 degrees Fahrenheit (24 to 26 degrees Celsius). If it reads lower, your fermentation will be slow from the start, and no amount of warm-room trickery later fully makes up for a cold start.

To hit that target, warm the water. As a rough rule, use water about 10 to 15 degrees Fahrenheit (5 to 8 degrees Celsius) warmer than you want the dough to end up, because mixing with room-temperature flour cools it down. In practice, that often means water at 85 to 95 degrees Fahrenheit (29 to 35 degrees Celsius) in a cold kitchen, rather than the lukewarm water you would use in summer. Do not use water hotter than about 110 degrees Fahrenheit (43 degrees Celsius). Above that, you start damaging the yeast, and a dough mixed with too-hot water can ferment unevenly, with the outside overactive and the inside sluggish. Warm, not hot, is the rule. If your kitchen is very cold, warm the bowl too, by rinsing it with warm water and drying it before mixing, and warm the flour by bringing it into the kitchen the night before, rather than using it straight from a cold garage or pantry.

Warm spots that actually work

Once the dough is mixed warm, it needs to stay warm. The best warm spot is one that is steady, gentle and draft-free. Here are the options that work, in order of reliability.

The oven with the light on

Put the covered bowl in the oven, with the oven off and only the light switched on. The light usually raises the temperature inside to 75 to 80 degrees Fahrenheit (24 to 27 degrees Celsius), which is ideal. Put a sticky note on the oven controls so nobody preheats the oven with your dough inside. This is the most common winter baking accident, and it ruins a whole day's work in minutes.

On top of the fridge

The top of the refrigerator is a few degrees warmer than the counter, because warm air rises and the fridge gives off a little heat. It is not a dramatic difference, but it is steady, and it is often enough to keep a dough moving in a cool kitchen. Keep the bowl away from the edge and away from direct drafts.

A warm water bath

Set the bowl in a sink or basin of warm water, not hot, and refresh the water every hour or so. This gives gentle, even warmth from all sides. Do not let water get into the dough, and do not use water hot enough to cook the outside of the dough. The water should feel comfortably warm to your hand, about 90 degrees Fahrenheit (32 degrees Celsius) at most.

A proofing box or insulated cooler

A cheap insulated cooler with a jar of warm water inside makes an excellent proofing box. The insulation holds the temperature steady for hours, which is exactly what a cold kitchen lacks. A heating pad on its lowest setting, placed under or beside the bowl but not touching it directly, inside an insulated box, works even better. Keep the pad on low. The goal is a steady 75 to 78 degrees Fahrenheit, not a sauna.

What does not work well is a radiator, a wood stove, or a spot right next to a heater. Direct heat makes the outside of the dough ferment fast while the inside stays cold, which gives uneven flavour and a dough that is overproofed on the outside and underproofed in the middle. If the only warm spot is near a heater, keep the bowl at least a foot away and cover it well.

 

Feeding your starter in winter

A cold kitchen starter needs three changes: warm water, more time, and sometimes a warmer home. Feed with water at 80 to 85 degrees Fahrenheit (27 to 29 degrees Celsius), so the fed starter starts warm. Give it 8 to 12 hours to peak instead of the 4 to 6 hours you might expect in summer, and keep the jar in the same warm spot you use for dough, not on a cold windowsill or a stone countertop. A jar sitting directly on a cold stone counter loses heat through the base, so put a folded cloth under it. If your starter still will not double, feed it twice a day for a few days with warm water, discarding as usual, to rebuild the population. Our starter guide explains the early days, and the same patience applies in winter to a mature starter.

Do not be tempted to fix a slow starter by feeding it a much larger ratio, like 1:10:10, in the hope that more food will make it stronger. In a cold kitchen, a large feeding just dilutes the culture further and takes even longer to peak. A 1:1:1 or 1:2:2 feeding with warm water, given plenty of time, is more reliable. And do not keep a starter in the fridge and expect it to bake the next morning without a warm-up feed. A fridge starter needs at least one, and usually two, warm feeds before it is ready to lift a loaf in winter. Plan that into your schedule, or the loaf will be the thing that teaches you the lesson.

Adjusting the bake itself

Winter changes the bake, not just the rise. Cold dough takes longer to bake through, and a cold Dutch oven or baking stone will steal heat from the loaf. Preheat your Dutch oven for a full 45 minutes to an hour in winter, longer than you might in summer, so it is thoroughly hot. If you bake on a stone or steel, give it the same long preheat. Bake to internal temperature, not to colour. A winter loaf can look done on the outside while the centre is still gummy, because the cold dough started further behind. Aim for 205 to 210 degrees Fahrenheit (96 to 99 degrees Celsius) in the centre for a rustic loaf, and 195 to 200 degrees Fahrenheit (90 to 93 degrees Celsius) for a pan loaf. If the crust browns too fast while the centre catches up, tent the loaf loosely with foil for the last part of the bake.

Steam matters too. A cold oven loses steam faster, because the cold surfaces condense it. If you bake in a Dutch oven, that is less of a problem, because the pot traps steam around the loaf. If you bake on a stone with a tray of water, use boiling water in the tray and work quickly when loading the loaf, so the oven does not lose too much heat with the door open. Every second with the door open in a cold kitchen is heat you have to win back.

A winter baking schedule

Here is a schedule that works in a kitchen at 65 degrees Fahrenheit (18 degrees Celsius). It is longer than a summer schedule, and that is the point. Trying to force a summer schedule in winter is how loaves fail.

• Evening before, 8:00 pm: Feed the starter with warm water and leave it in a warm spot overnight.
• Morning, 8:00 am: Check the starter. It should have peaked or be close. Mix the dough with warm water, aiming for 76 degrees Fahrenheit (24 degrees Celsius) dough temperature.
• 8:30 am: Rest, then stretch and fold at 9:00, 9:30 and 10:00.
• 10:00 am to 4:00 pm: Bulk ferment in a warm spot, 6 hours or more. Look for a 50 to 75 percent rise, a puffy, jiggly dough, and a domed surface.
• 4:00 pm: Shape gently and place in a floured banneton. If you have one, our banneton guide helps with sizing.
• 4:30 pm to 6:30 pm: Final proof at room temperature, or refrigerate overnight and bake in the morning. The fridge option is often the easiest in winter, because it removes the pressure of a long evening proof.
• Bake: Preheat the Dutch oven for 45 to 60 minutes, bake covered for 20 minutes and uncovered for 20 to 25 minutes, to an internal temperature of 205 to 210 degrees Fahrenheit.

If that schedule is too long for your day, the fridge is your friend. Mix in the morning, bulk ferment through the day in a warm spot, shape in the evening, and refrigerate overnight. Bake straight from the fridge the next morning. That is the cold-proofing method, and it turns winter's slowness into an advantage, because the cold fridge proof is controlled and predictable, unlike a cold kitchen proof, which is not. Our three timelines show other ways to fit a bake around a working day, and the overnight fridge version is the one most winter bakers end up using.

Mistakes to avoid in a cold kitchen

Adding more starter to speed things up

Doubling the starter does not double the speed, and it makes the dough more acidic, which can weaken the gluten and give a sour, slack loaf. Fix the temperature, not the starter amount. Warm water and a warm spot do more than extra starter ever will.

Putting the dough somewhere hot

A dough that goes from 60 degrees to 95 degrees Fahrenheit in an hour will ferment unevenly and can develop off flavours. Gentle, steady warmth is the goal. If you use a heating pad or a warm oven, check the temperature with a thermometer. If it is above 85 degrees Fahrenheit (29 degrees Celsius), it is too warm for bulk fermentation.

Judging readiness by time

In winter, time is the least reliable guide you have. Two kitchens at the same nominal temperature can ferment at different speeds because of drafts, countertop materials and humidity. Judge by rise, jiggle, dome and poke, not by the clock. A dough that has risen 50 percent and jiggles is ready, whether that took 4 hours or 9.

Skipping the thermometer

Guessing dough temperature in winter is guessing the whole bake. A thermometer costs little, takes seconds to use, and removes the biggest variable in cold-weather baking. Measure after mixing, and again before shaping if you are unsure. It is the cheapest upgrade a winter baker can make, and it matters more than any new piece of equipment.

Frequently asked questions

How cold is too cold for sourdough?

Below about 60 degrees Fahrenheit (15 degrees Celsius), bulk fermentation becomes very slow and unreliable, and below 50 degrees Fahrenheit (10 degrees Celsius) it effectively stalls. That does not mean the dough is ruined. It means it needs warmth. Move it to a warm spot, give it time, and it will usually recover, unless it has been sitting cold for days and has become very acidic. If your kitchen is regularly below 60 degrees, a proofing box or a warm oven is not a luxury. It is the tool that makes winter baking possible.

Can I leave dough to rise overnight on the counter in winter?

Yes, and winter is actually the best season for it, because a cool kitchen slows fermentation enough that an overnight counter rise does not overproof the way it would in summer. Mix in the evening, leave the covered bowl on the counter in a kitchen at 60 to 65 degrees Fahrenheit (15 to 18 degrees Celsius), and shape in the morning. Check the dough before shaping. If it has more than doubled and smells strongly acidic, it has gone too far, and you should shape it gently and bake it in a pan rather than as a free-standing loaf.

Should I use more whole wheat in winter?

Whole wheat ferments a little faster than white flour, because it carries more minerals and microbes, so it can help a sluggish winter dough move along. But it also makes a denser loaf, so it is not a free fix. A 20 to 30 percent whole wheat blend is a reasonable winter adjustment, and it adds flavour that suits the season. Do not jump to 100 percent whole wheat in the middle of winter and expect the loaf to behave like a summer white loaf.

Why is my winter loaf gummy inside?

Usually it was sliced too soon, underbaked, or both. Cold dough needs a longer bake to reach temperature in the centre, and a loaf that feels done on the outside can still be setting inside. Bake to 205 to 210 degrees Fahrenheit for a rustic loaf, cool for at least 2 hours, and slice only when the loaf is fully cool. Our dense and gummy diagnosis covers the other causes, including underproofing, which is common in winter because bakers shape too early, impatient with a slow rise.

Does cold weather change how I store bread?

A cold, dry house can stale bread faster, because dry air pulls moisture from the crumb. Keep the loaf in a cloth bag or bread box, not out on the counter, and slice only what you need. In a very dry winter house, a plastic bag for the second day can help, even though it softens the crust. The crust is a trade-off, and in winter, a soft crust on day three beats a rock-hard loaf.

Is winter sourdough actually better?

Many bakers think so, and there is a reason. Slow fermentation builds more complex flavour, with lactic notes that are creamy and mild rather than sharp. A winter loaf that took 8 hours to ferment will often taste better than a summer loaf that took 4, even if the summer loaf looked prettier. The trick is to let winter be slow on purpose, with warm water, a warm spot and a patient schedule, rather than fighting it. Once you stop expecting summer timings in January, winter becomes the season when your bread tastes its best, and the kitchen smells like a bakery on the coldest days of the year, which is no small thing.