Sourdough Starter Science: DIY Levain

Before you can make your very own sourdough bread, you need an active starter or levain. Sourdough differs from other yeast breads in both preparation and flavor. Rather than using commercially available baker's yeast, sourdough utilizes wild yeast found in the air. The mildly sour flavor of the bread is in part the result of the presence of lactic acid produced by lactobacilli. With the help of this tutorial, you too will be on your way to making delicious homemade sourdough bread.

Day 1: Create Starter Mixture

Ingredients:
• 1 cup whole wheat or whole rye flour
• 3/4 cup pineapple juice (at room temperature)

• Mix until all of the flour is hydrated
• Scrape mixture into clean quart-size wide mouth glass container
• Cover container with paper towel, cheesecloth, or coffee filter and secure with a rubber band
• Mark the level of the starter with tape or rubber band
• Leave at room temperature for 24 hours

Day 2: Add Flour and Mix Well

There will likely be very little change in the appearance of your starter.

• Scrape starter mixture into a mixing bowl
• Add 1 cup of unbleached all-purpose or unbleached bread flour
• Add 1/2 cup pineapple juice (at room temperature)
• Mix well.
• Wash and dry your glass container
• Scrape starter mixture into container
• Mark and cover container just as you did on day 1
• Leave at room temperature for 24 hours

Day 3: Divide and Conquer

By this point, your starter mixture may have risen some and there might be a few bubbles. Whether you notice any fermentation or not, discard half of the mixture (or give to a friend). Next you will:

• Pour starter mixture into mixing bowl
• Add in 1 cup of unbleached all-purpose or bread flour
• Add 1/2 cup filtered water (room temperature)
• Wash and dry your container
• Scrape the mixture into container
• Mark and cover as before
• Let sit at room temperature for 24 hours

Day 4: Size Multiplication Or...

At this point, the starter mixture should have at least doubled in size. If it hasn’t doubled in size, allow it to sit at room temperature for another 12 to 24 hours. If it has indeed doubled in size, repeat instructions for Day three.

Day 5: Feed the Yeast

Feed the your starter 1 cup flour and 1/2 cup water as you did on day three, every 12 hours.

Day 6: If You Got a Rise...

If your starter has been active and always doubles in size (or more) between feeding then your starter is ready to bake with. If you are not yet ready to bake, proceed to the next step. If your starter still seems a little sluggish or is not at least doubling in size between feedings continue with the twice daily feedings as on you began on Day 5.

Day 7: Caring for Your New Pet

If you aren't yet ready to bake, you can refrigerate your starter and feed once per week.