100% Hydration Sourdough Starter: Beginner's Guide

A 100% hydration sourdough starter is the most commonly used type in bread recipes. It is easy to maintain and works well with most sourdough baking.

In this guide, you will learn about starter hydration, the various hydration levels, and how to adjust them.

What is sourdough starter hydration?

Sourdough starter hydration refers to the ratio of liquid (usually water) to flour. It is expressed as a percentage and affects the consistency or thickness of your starter.

• A higher hydration level means your starter is more liquid and runny.
• A lower hydration level means your starter is firmer and dough-like.

This balance impacts how your starter ferments and affects the final flavor and texture of your bread.

Types of sourdough starter hydration

For beginners, I highly recommend using a 100% hydration starter, which is the standard in sourdough baking. If a recipe does not specify the hydration level, it typically assumes a hydration level of 100%.

Here are the three main types of starter hydration:

1. 100% hydration starter: Equal weights of water and flour.
2. Lower hydration starter (below 100%): More flour than water, creating a stiff, dough-like starter.
3. Higher hydration starter (above 100%): More water than flour, resulting in a liquid, pancake batter-like consistency starter.

How to make a 100% hydration starter

To make and maintain a 100% hydration starter, feed it with equal weights of flour and water (by weight).

For example:

• If you have 20 grams of starter, you would feed it 20 grams of water and 20 grams of flour. This keeps the water-to-flour ratio at 1:1 by weight.
• If you have 5 grams of starter, you could feed it 30 grams of water and 30 grams of flour. This still results in a 100% hydration starter, as the weights of water and flour are equal (30g of water = 30g of flour).

Use a pocket gram scale for this process. Measuring by weight, not volume, provides the best accuracy and consistency in your starter.

How to adjust your sourdough starter hydration

Changing your starter hydration is simple but requires precision and patience. Use a digital scale to measure carefully. Minor changes to the water-to-flour ratio can make a big difference.

For example, adding 10-30% whole-grain flour, like whole wheat or rye, can affect hydration because these flours absorb more water.

Experiment with different flours and hydration levels to create a starter that best suits your bread and personal taste. However, I recommend sticking to the basics if you are starting out.

Let's talk sourdough

Have you started a 100% hydration starter yet? What surprised you most about the process? Share your story in the comments.

Ready to keep learning?

Now that you know the basics of starter hydration, there is even more to learn about it. Check out these helpful guides:

• Sourdough Starter Ratios
• How To Feed A Sourdough Starter
• Liquid Sourdough Starter Vs. Stiff Starter