How Baker's Percentages & True Hydration Work
What is a Baker's Percentage?
In baking, volume measurements (cups, spoons) are notoriously unreliable because flour density fluctuates. Instead, artisan bakers use Baker's Percentages, where the Total Flour Weight is always defined as 100.0%. Every other ingredient (water, salt, starter, yeast) is calculated as a direct proportion relative to that flour base.
For example: with 500 grams of flour and 75% hydration, you need 500 × 0.75 = 375 grams of water. With 2% salt, you need 500 × 0.02 = 10 grams of salt.
The Sourdough Starter "Hydration Trap"
A common mistake when formulating sourdough recipes is ignoring the flour and water already present inside the sourdough starter.
A standard 100% hydration starter is 50% flour and 50% water by weight. If you mix in 100 grams of starter without correcting your water, you are inadvertently pouring an extra 50 grams of water into your dough. This can spike your effective hydration from 75% to nearly 78%, causing the dough to become soupy, lose its structure, and spread flat in the oven.
SpinFoundry solves this deterministically by separating the starter into its constituent parts:
Typical Hydration Guidelines
- 50% – 58%: Stiff doughs (Bagels, pretzels, pasta).
- 60% – 66%: Standard table bread, baguettes, sandwich loaves.
- 70% – 78%: Artisan sourdough country loaves with open, custardy crumb.
- 80% – 90%+: Ciabatta, pan de cristal, high-hydration focaccia.