08/24/2026
Every August, I run a series of tests on my sourdough starter to benchmark is strength. I also test the impact of different flours, hydration, feeding ratios and temperature.
I’ve developed this testing setup over the last 4 years, and I believe it is a one-of-a-kind setup.
Many people assess the “strength” of their starter by observing how quickly it doubles, for example, but the visible rise in the jar is impacted by many variables (including the shape and size of the jar!).
I believe the true test of starter rising power is to measure the actual amount of Carbon Dioxide created by the starter. Using an innovative sealed pressure vessel, I can compare the cumulative CO2 generated by a sourdough starter — in a very controlled environment.
I also run parallel samples where I measure and compare the time to peak, the height of the rise, pH, and temperature.
I’ve run hundreds of these tests over the years, and I’ll be sharing some of the study results over the coming weeks.
Caution: Don’t try this at home! In an airtight vessel, 5 grams of starter can create as much pressure as in your vehicles tires. Very dangerous, especially in glass jars (don’t ask me how I know).