You’re only 7 days away from infinite sourdough bread


Naturally Leavened Bread



How does one begin the journey of making naturally leavened bread?
It starts with an incredible sourdough starter from scratch

by Maurizio Leo, baker and founder at The Perfect Loaf


created my sourdough starter over five years ago, and it’s the same one I use to this day. Besides, when I’m baking, it does most of the heavy lifting (bread-nerd joke, sorry).

Back in the early days it was the quintessential rebellious child. Sometimes it wouldn’t show any fermentation activity, and at other times it was utterly unruly.

In the beginning, I didn’t realize what it needed to thrive. I didn’t see how important timely refreshments (also called a feeding, where we mix in fresh flour and water) were, or how much temperature impacts fermentation.

The key to raising a well-adjusted starter is to be observant of its needs, give it space to grow, and adjust refreshments to encourage maximum fermentation activity. A healthy starter means great bread.



At least two ¾-liter glass jars
Whole grain rye flour
Unbleached, all-purpose, white flour (organic if possible)
Silicone spatula
Instant-read thermometer


Day 1

In the morning, place an empty jar on the scale and tare so that it reads 0 grams. To that jar add 100 grams whole grain rye flour and 150 grams water into one of the clean jars and mix together.

Stir vigorously until all dry bits are incorporated. Keep this mixture somewhere warm in your kitchen, 80 F to 85 F (26 C to 29 C) is ideal. If it’s cool in your kitchen, warm the water to 80 F (26 C) before mixing. Let the mixture rest out of direct sunlight for 24 hours.


Day 2

Place your second, empty jar on the scale and tare. Scoop in 75 grams of the mixture that has been resting for 24 hours, discarding the rest. Next, add 50 grams rye flour, 50 grams all-purpose flour, and 125 grams warm water.

Mix well until all dry bits are incorporated, cover and place in the same warm spot until day three.

Discard the rest of the mixture in the first jar and clean it in preparation for the next day.


Day 3

On this day, you may be starting to see more activity, or you may see none. However, my mixture started to show the beginning signs of beneficial yeast and bacteria taking hold.

Repeat the steps you performed on day two.


Day 4

In the morning, you should start to see signs of fermentation activity if you haven’t already. There will be bubbles scattered on the sides and top, and the level of the mixture might have risen and fallen a little (evidenced by streaks on the sides of the jar).

Refresh in the same way as on day three. Mix thoroughly, cover, and let rest for 12 hours. After this 12-hour rest, discard down and refresh again with the same ratio of ingredients, and let rest overnight.

Discard the rest of the mixture in the first jar and clean it in preparation for the next day.


Day 5 and 6

For days five and six, continue refreshing with the same ratio of ingredients as day four, twice a day, as fermentation activity increases more and more.


Day 7 and Onward

In the morning on day seven, place a clean jar on the scale and tare. Scoop in 50 grams of the mixture from the jar that fermented overnight. To this, add 100 grams all-purpose flour and 100 grams water (no rye flour is needed).

Mix thoroughly, cover, and let rest for 12 hours. In the evening (after about 12 hours), refresh again with the same ratio of ingredients and let rest until the next day.

At this point you should start to see the height of your starter rise and fall in the jar predictably each day. This periodic behavior is a good indicator that it is strong enough to use for your first loaf of bread.

Day 8
Day 8

If your starter is still struggling to show vigorous activity, keep refreshing with the same ratio of ingredients for another day, or several more, until things pick up. This process can sometimes take longer, depending on the flour used and the environment (especially if it’s cool in your kitchen).

Be patient and stick to the schedule, and eventually a stable starter will take hold.

The starter will continue to develop flavor and strength over the next week and into the future. With a strong starter, you can now use a portion of it when “mature” (when it’s risen to maximal height) to make a leaven.

Based on your baking frequency, you can feed your starter once a day or use the refrigerator slow it down.

Read the full post, see more photos and get sourdough recipes on The Perfect Loaf.


Helpful Hints

Use water that’s filtered with a carbon filter or distilled water.

After you put your starter mixture in the jar, keep the jar covered, but not sealed, during the rest of the process. Either a porous cloth or a lid resting on top of the jar will work well. Use containers with enough headspace for the mixture to rise. Additionally, place your jar in a bowl while it’s resting in case the mixture spills over.

There’s often a surge in fermentation activity during the first couple days of the process, probably caused by other yeast and bacteria that will eventually die off. Don’t be fooled by this lapse in activity; continue with the schedule and eventually the desired yeast and bacteria will move in and stabilize.

The entire process is extremely temperature-dependent. By keeping the contents of the jar around 80 F (26 C), you’ll ensure a favorable environment and speed things up dramatically.




Naturally Leavened BreadYou're only 7 days away from infinite sourdough bread