Any place where sourdough bread is made plays host to a lively and complex microbiome known as a sourdough starter.
This community of wild yeasts and bacteria—yes, sourdough also comes from a SCOBY (Symbiotic Culture Of Bacteria and Yeast)—is easy to capture and cultivate and requires nothing fancy in the way of kitchen gadgetry. A kitchen scale is helpful but not essential: a couple of one-quart containers with lids, filtered water, and basic flour are all that’s needed.
Wild yeast is too small to see but it’s everywhere and can be encouraged to thrive with a simple daily routine. Once established, a starter can be fed weekly or even kept happily, albeit sleepily, in the refrigerator for months.
Ignore the romantic claims that a starter needs to be purchased or collected from a particular place. The story of the “heirloom starter”, one passed down for generations, is well loved but is, quite probably, a kitchen myth. According to several studies on the composition of sourdough starters, the kitchen environment has the most impact on the cultures present. In other words, for a starter to remain the same as when it started, it would need to remain in the same kitchen, prepped by the same person/people, with the same water and the same flour.

Kneading a sourdough loaf. Photo Mariah Green
Make it a habit
Your ability to stick to a schedule is critical when beginning a sourdough starter and quite helpful when establishing a baking routine. I suggest that the feeding of the starter be linked to something you do every day anyway, like making coffee. A vigorous stirring to combine the ingredients and a moment to clean the utensils can all be accomplished while preparing one’s morning coffee.
Establish a place in your kitchen for the starter to occupy. This should be in a cooler spot, out of the direct sun; a cupboard corner or the back of a countertop are good choices. While the refrigerator is certainly an option, personally I only use the fridge when I’m not baking very much and want to slow the starter down.
For maximum vitality, flavor and vigor, keep the starter at ambient temperature. In the summer when temperatures rise, the starter will be very active and the amount of starter required to raise your loaves can be reduced. In the cooler months, the starter percentage can be increased. Establishing a good daily routine will reward you with a reliable kitchen companion that will raise your loaves and stamp them with your own signature terroir, the flavors of your particular environment.
Heirloom sourdough
Cultivate a small quantity of starter and build it up on the days when you plan to bake. On bake days the starter should be fed with a freshly milled, whole-grain flour in proportions to suit the number of loaves that will be produced. Fresh whole-grain flour will stimulate the starter into a lively state that will bring the desired results of well-developed crumb structure, a crisp crust, and a complex flavor.
You’ll need:
- A kitchen scale (not essential but recommended for better accuracy)
- 2 containers (1-quart each) with lids
- Mixing spoon
- Dedicated storage spot for the starter
- Organic or heirloom all-purpose flour (try Roan Mills heirloom flour)
- Filtered water
How to capture wild yeast
Day 1
Put a 1-quart container on a scale. And set the weight to zero.
Put 115 grams of flour and 115 grams of filtered water into the container and stir vigorously to combine, cover the container and place it in a designated spot in your kitchen or pantry.
If you don’t have a scale, use about 1 cup flour to ½ cup water. Adjust ratio to get starter the consistency of thick pancake batter.
Day 2
Put 115 grams (or just about a cup) of the young starter into a clean 1-quart container and add 115 grams of flour and 115 grams filtered water. Stir vigorously to combine, cover and return to its designated spot.
Day 3
Repeat day 2 and pay attention to any changes that may begin to develop. A sour smell and a few bubbles are signs that the starter is ripening.
Day 4
Place half of the starter into the clean container with 115 grams of flour and 115 grams of filtered water, stir vigorously to combine, cover and return it to its designated spot.
Day 5
The starter should be ripening nicely by now; notice the changes in texture and smell. It may be very bubbly or even frothy.
To test the ripeness, fill a glass with water and drop a spoonful of starter into the glass. If it floats for a few seconds before sinking then it is ready to use. If it sinks immediately, it needs more time; simply continue the steps above for a few more days.
Maintaining the starter between bakes
Once the starter is ripe it needs to be maintained.
This means that you will toss 80% of it each morning* (or once a week if maintaining the started in the fridge) and replace that amount with equal parts water and flour.
The routine starts with scooping about a cup of starter into the clean quart container and adding 115 grams each of flour and water. Proceed as before, stirring the starter vigorously, covering and allowing it to rest on the counter. If using the slow maintenance, put the starter back in the fridge after it starts to grow.
*The discarded starter can be used in pancakes and waffles or composted. It can also be dried and stored in a paper bag. A dried starter can be used to start a new sourdough starter.
Baking sourdough bread
On bake day, start with a room-temperature starter.
Scoop about a cup of starter into a larger clean container and feed it with 115 grams your choice of whole-wheat, rye, spelt, einkorn, or all-purpose flour and 115 grams of filtered water. The whole-wheat flour will make the starter very lively; it should pass the float test before 6 hours have passed.
Basic Sourdough Bread
Ingredients
- 1,000 grams (7 1/2 cups) milled whole-wheat flour
- 850 grams (3 3/4 cups) filtered water
- 20 grams (2 1/2 tablespoons) sea salt
- 200 grams (3/4 cup) sourdough starter
Instructions
- Put the flour, water, and salt in a large bowl. Mix until combined and cover with a kitchen cloth. Leave this to rest while the starter ripens.
- Once the starter passes the float test, usually after 5 or 6 hours, add to the well-hydrated dough.
- Mix well, cover and allow the dough to rest for 20 minutes before stretching and folding the dough 3 or 4 times. Cover and repeat the stretch-and-fold sequence twice more at 20-minute intervals.
- At this point, the bulk dough can be left to ripen for several hours at ambient temperature. As it develops it will rise, so the container needs to be large enough to accommodate the increase.
- When you are ready to shape the dough, pull it from the container and divide the dough into 2 equal parts.
- Shape the bread and place in a floured breadbasket (or improvise one with well-floured kitchen towels draped into a 1-quart bowl).
- These can be slipped into a large plastic bag and held in the fridge for up to 24 hours before baking. Alternately, they can be left at ambient temperature for an hour or 2 and baked the same day. Preferences for the long, cold fermentation are valid. The acids from the sourdough starter break down the proteins in the wheat; this process makes the nutrients more available and the final bread more digestible. The flavor and keeping quality of the bread are also noticeably improved.
- That said, a bake that starts and finishes on the same day still produces very delicious results.
After the starter ripens, reserve about ½ cup, feed it the maintenance dose of flour, and set it aside for another day.
On baking
A cast-iron double Dutch oven makes a great bread oven. Place it into a cold oven and preheat to 500oF.
Once at temperature, carefully remove the hot Dutch oven from the oven and place it on the stove. Remove the lid and plop the dough into it. Carefully score the top and cover the loaf with the hot lid. Quickly return to the oven.
After 20 minutes, remove the lid and drop the temperature to 400oF. Continue baking for 35–40 minutes or more, until the desired color is achieved. Remove from Dutch oven and allow to cool on a wire rack.
How to slow down the sourdough starter
Sourdough starter can be frozen with good results. Freeze it after it’s been fed and ripened for several hours. To activate, thaw it and follow the regular maintenance schedule. It should bounce back to full vigor within a couple of days.
Final notes
The process of maintaining the sourdough starter becomes intuitive over time. The look and smell of it will become familiar and working with it will become second nature. Stick with it even if the bread isn’t perfect initially. Eventually, the results will please you and bring joy to those who break bread with you.