For best results, begin a sourdough starter culture using organic whole grain flours, especially rye, which is very high in nutrients and fermentable sugars.
It’s difficult to begin a starter with all-purpose flour alone. Mixing by hand adds bacteria and yeast to your culture, but it’s not necessary for success.
However, working in an environment that is too sterile or one that has been cleaned with heavy cleaning products and antibacterial agents will work against you. Your starter should be ready to use for making bread in a week, but it will be more reliable and have a better flavor profile in 2 to 3 weeks.
There will be more homofermentative bacteria (lactic acid with an abundance of yeast) during the first week, and in a few weeks, more heterofermentative bacteria (lactic acid and acetic acid for a better balance of yeast and bacteria) will have taken hold, giving your bread more complex flavors. Once established, continue to feed it with your flour of choice and adjust the hydration to your liking.
Measuring by weight is far more accurate than measuring by volume (i.e. cups or spoons). It’s not completely necessary to use a scale to make a sourdough starter or bread, but the process is more successful with a scale.
Avoid using tap water. Chlorine and chloramines commonly present in tap water work against natural bacteria and yeast.
Whole grain organic rye flour
Spring water/filtered water
Whole grain organic wheat flour
Organic all-purpose flour
Digital scale that measures in grams with tare (zero out) function
1-quart Mason jar
Day 1 Mix 100g of whole grain rye flour and 160g of water in your vessel and stir with a wooden spoon or chopsticks. Scrape the sides clean with a rubber spatula and cover loosely with a lid. Allow it to sit for 24 hours in an area where the room temperature will remain consistently between 72º–80º. Keep away from other cultures, compost bins, and moldy fruit by at least 6 feet to avoid contamination.
Day 2 Stir mixture and discard half of it. Add 100g of whole grain rye flour and 160g of water and mix well. Scrape the sides clean, cover with lid, and let it sit for 24 hours. Mixture should double in size and fall.
Days 3–6 Increase feedings to twice a day. Each time, stir mixture and discard half of the starter and add 50g of whole grain rye flour and 80g of water and cover. Mixture should smell sweet and yeasty, not foul or off-putting. Continue to scrape the inside of the container clean with a rubber spatula and mark the level of freshly mixed starter on the outside of your container with tape or a rubber band so you can track the activity. It should rise and fall with each feeding.
Day 7 At this point you should be able to feed your starter with a larger amount of flour. In a new container, measure out 50g of starter. Add 100g of organic flour (50g wheat and 50g rye) and 100g of water. If the culture doubles and falls, it’ll be ready to use for bread, but I recommend continuing to feed for 2 more weeks. Continue feeding with the 100g mixture once a day. Switch to 50g flour and 50g water once it is healthy and established. Organic all-purpose flour is fine for maintaining the starter after a few weeks of regular feedings have passed, or make a mixture of 50% all-purpose flour and 50% whole grain flour for feedings.
Remember to discard extra starter; there really is no need to keep more than 1 to 2 cups total. The larger in volume your mother starter is, the more you have to feed it to keep it healthy.
Maintain your starter either at room temperature for baking regularly or store it in the refrigerator with weekly room temperature feedings if you don’t bake very often.
MAINTAINING AT ROOM TEMPERATURE
If keeping the starter at room temperature, feed it at least once a day, though twice is best, especially in warmer months. Liquid accumulating on the top or an overly acidic smell are signs that suggest the starter is not getting enough food. If this happens, pour off the liquid before feeding the starter again. You can also discard all but a tablespoon of starter and transfer it to a clean jar before feeding it to freshen it up.
With a digital scale, zero out the weight of your crock. Add 50g of organic all-purpose flour and 50g of spring or filtered water. Mix well and scrape sides clean with a spatula and cover with a cotton dishcloth to absorb any condensation. Scraping the sides clean will prevent thick clumps of starter from forming on the inside of your container. Cover with lid.
The starter will grow if kept at room temperature. Don’t let it accumulate to more than about 2 cups in volume. The larger the starter, the more “mouths” to feed, and the culture can weaken because 50g flour and 50g water will not be enough food. Discard the extra starter or make pancakes, waffles, crackers, and more with the excess.
If feeding twice a day in the summer months is undesirable, you can remove the bulk of your starter and feed a smaller amount (10g starter) with 50g flour and 50g water once a day. If you don’t want to throw excess starter away, save the discarded starter in a larger container in the refrigerator to make your sourdough discard recipes.
MAINTAINING IN THE REFRIGERATOR
Starter kept in the refrigerator will need to be fed once a week.
Take your starter out of the refrigerator. Remove ¼ cup of starter and set it aside.
Discard the remaining starter and rinse out your container with hot water. Place clean container on scale and zero out the weight. Add reserved ¼ cup of starter, noting the weight in grams and adding equal weight in grams of spring/filtered water and organic all-purpose flour. Mix and allow to double in volume at room-temperature (roughly 4 to 6 hours) before returning to the refrigerator to store.
To bake bread, three room-temperature feedings are recommended prior to the bread-making process in order to wake up the starter. For example, if you wanted to bake on Saturday, take the starter out of the refrigerator Thursday morning and continue to follow the feeding instructions but leave it at room temperature. Feed it again with 50g flour and 50g spring or filtered water on Thursday evening and Friday morning, and make your levain Friday evening for starting your dough Saturday morning.
The recipes that follow and many others online can help keep your starter occupied. Store starter dough for a week before it gets too sour, but don’t store more than 2 cups at a time.
Don’t feel guilty if you don’t have time to use all your excess starter and you’d like to throw it away.