How To Make A Sourdough Starter From Scratch
A basic sourdough recipe requires just a few simple ingredients: flour, water and salt. But the magic happens when you add the sourdough starter!
Flour naturally contains a variety of yeasts and bacteria. The sourdough starter is, in essence, a fermented mixture of flour and water. This mixture includes microorganisms that will help the dough to rise.
If you have the right tools, a bit of patience and some discipline, making a starter from scratch won’t be a difficult task! However, once you’ve developed a good starter, you need to be consistent and take good care of it. (You can find out more in our starter maintenance article).
In order to create a starter from scratch, you’ll need to allow about 7 days for the process to complete—this is to give enough time for the mixture to develop a stable culture of the necessary bacteria, ensuring that the starter is fully ripe and active before you use it to bake bread with it.
Our starter recipe uses just 20g of flour and 20g of water on day one of the process. You may have seen other starter recipes asking for as much as 500g of flour on day one, but, in our experience, building a large amount of starter at the beginning of the process may be unnecessary, as you would end up wasting a lot of your precious flour! In fact, you only really need a tiny bit of active starter—as little as 5g—to make a loaf of bread, so the amounts in the recipe below should be more than enough to get you started.
Equipment and ingredients
Strong wholemeal/whole wheat bread flour
In this recipe we use wholemeal/whole wheat flour, but some bakers like to use rye or strong white bread flour instead, or a combination of the above. Each flour will produce a starter with a slightly different flavour, texture and consistency. You can always experiment later!
Water
The temperature of the water used to make the starter should be at about 27°C/80°F. This will allow for the flour and water to bond within the specified amount of time.
NOTE: In bread making, the measurement for water is usually done in grams, not millilitres—the conversion is 1:1. This means 10ml of water is 10g of water.
Small jar or container
Ideally clear glass, with straight walls, around 100ml, with a lid. You want your starter to ‘breathe’, so don’t close it tight.
Is good practice to change the jar with each feeding, otherwise cleaning it becomes a hassle. So getting a couple means you’ll always have a clean one ready to use, when it’s time for feeding your starter again.
And you don’t necessarily need to buy a jar—for the purpose of storing your starter, you can simply use a small jam jar with a lid. Just make sure you place the lid loosely on top.
Digital scale
Because of the precision required when measuring ingredients when feeding your starter, you’d ideally want to use a digital scale. Any variations in the amounts used may have an impact on your starter and subsequently on your bake—so if you don’t have one, get one!
Cooking thermometer
Temperature is important when it comes to the water you use for your starter (and the water you add to the dough when making sourdough). For higher precision, we use a digital thermometer.
Steps
STAGE 1 — Preparing the culture
(Day 1; 8am)
Measure 20g of strong wholemeal/whole wheat flour and place it in the jar. Add 20g water (27°C/80°F). Mix with a spoon until the mixture resembles a thick batter and there are no flour lumps. Loosely cover with the lid and leave it to ferment at room temperature for 2 days.
We usually place the starter on the countertop—just make sure your jar is away from any direct sunlight, ideally in a warm area of the kitchen. Once active, the mixture will rise and fall inside the jar. Placing a rubber band around the container will help you follow the fermentation stages of your starter.
Flour mixed with water for the first time.
(Day 2; 8am)
On the second day, check if any bubbles have formed around the sides and on the surface, and if the starter has increased in size.
The colour of your starter will start getting darker, and there might be some crust developing on the top of the mixture (and potentially some liquid). That’s normal.
Another thing you will notice is that, from the second day, the mixture may start to smell a little unpleasant. This means the starter has begun its fermentation process and is getting ready for the first ‘feeding’ (by ‘feeding’ we mean adding more flour and water to your starter).
Other than observing your starter, there’s nothing else for you to do on the second day.
STAGE 2 — Feeding the starter for the first time
(Day 3-4; 8am)
The starter will be ready for its first feeding once you notice visible signs of fermentation. At this stage, we will feed the starter once a day, for about a couple of days.
Signs of fermentation include changes in the smell of the mixture, while visible bubbles start to appear. The smell may become stronger or acidic, and the bubbles would make the starter increase in volume and then potentially deflate.
If no signs of fermentation are visible, wait another day. Be patient, the fermentation process and timings may vary depending on factors such as the type of flour used, the temperature in your kitchen, etc.
To feed the starter, take a clean jar and transfer 20g of your starter to it. Discard the rest. Add 20g water (27°C/80°F) and mix well. Then add 20g strong whole wheat flour and mix again until the mixture resembles a thick batter and there are no flour lumps.
Loosely cover with the lid and leave for another 24 hours.
On day 4, repeat the feeding process.
STAGE 3 — Training your starter (cyclical feeding)
(Day 5-7; 8am and 8pm)
At this stage, the starter should start increasing in volume in a more predictable manner (if it hasn’t already). It will slowly rise after each feeding and then begin to collapse again.
From now on, we will start feeding the starter twice a day, once in the morning and once in the evening. Remember, 8am and 8pm are only suggestions—you can pick times that are convenient to you, as long as they are roughly 12 hours apart. However, once you choose your preferred times, try to stick to them—this 12 hour routine will ensure that your starter is ready to be fed again at the right time.
The feeding process is the same as before, but with some small adjustments to the amount go the starter used—discard all but 10g of the starter and feed with 20g water (27°C/80°F) and 20g flour.
At the end of the week, your starter should at least double in size toward the end of each feeding cycle, signalling that it’s fully active. Now you know it’s ready for your first bread!
Fully active starter that is beginning to deflate, after having more than doubled in size. The bubbles on the side of the jar are a visible sign of the fermentation process.
NOTE: If you notice the starter doubling in size after day 2 or 3, do not bake with it just yet, as it’s not fully ready to be used. Be patient and follow the process as described for the full week before baking.
Fully ripe and active starter after several weeks of daily feeding.
Things to remember
Temperature
Keep your starter in a warm environment, ideally 26°C (79°F). Warmer temperature may speed up the fermentation process, while cooler temperatures will slow it down. If your kitchen is on the cooler side, you may need to allow more time (several extra days) for your starter to become ready to be used. To compensate for cooler temperatures, feed your starter with warmer water than the temperature specified above. However, this may not be sufficient to maintain the optimal temperature throughout the day. To keep your starter warm between feedings, you can place it in the oven with just the light on. Alternatively, you may decide to invest in a proofer. We recommend Sourdough Home from Brod & Taylor or Folding Proofer that can also be used to keep your dough warm during bulk fermentation.
Fermentation
After the initial days, you may notice increased activity in your mixture, followed by a potential decrease around day 3-5. If this occurs, continue with the specified feeding routine mentioned earlier. It's possible you'll need a few extra days for your starter to establish a strong culture.
Consistency
The mixture should resemble the consistency of thick pancake batter. Keep in mind that different flour types may result in slight variations, so if the mixture appears too thick or too thin, you can make subtle adjustments to the amount of flour or water during feeding.
Ready for baking
Your starter will be ready for baking when it consistently doubles in size for at least a couple of days, achieved through at least 4 feedings spaced 12 hours apart. Typically, this occurs around day 5-7 following the process outlined above. Remember to be patient; the wild yeast needs time to develop.
One crucial element of having a sourdough starter is its regular maintenance. To help you with that, we have created a Starter Maintenance Calculator, that will work out how much mature starter, flour and water to use based on your required ratio of the three ingredients. Also taking into account how much of the mature starter you want to use in the first place.
You can learn more about the calculator here.
Check our NEW Sourdough Fever Stencils!
