Desired Dough Temperature: How to Work Out Your Water Temperature

Dough temperature has a big effect on how fast sourdough ferments. The desired dough temperature (DDT) method tells you how warm or cool to make your water so the mixed dough lands where you want it.

The formula

For sourdough (which has a preferment, the starter) there are four temperatures, so the multiplier is 4:

water temp = (DDT × 4) − (room temp + flour temp + starter temp + friction factor)

For a straight yeasted dough with no preferment, drop the starter term and use × 3.

The method works in °C or °F, but use one scale for everything, including the friction factor. A friction factor of 2 °F is about 1.1 °C. Convert a temperature difference by multiplying by 5/9 only, without subtracting 32.

Worked example in °C

Target 25 °C; room 20 °C; flour 20 °C; starter 22 °C; friction 1 °C (gentle hand mixing).

Water = 25 × 4 − (20 + 20 + 22 + 1) = 100 − 63 = 37 °C.

Worked example in °F

Target 78 °F; room 68 °F; flour 68 °F; starter 72 °F; friction 2 °F.

Water = 78 × 4 − (68 + 68 + 72 + 2) = 312 − 210 = 102 °F (about 38.9 °C).

What target temperature?

Many sourdough recipes aim for a mixed dough of roughly 24–26 °C (75–79 °F). Warmer dough ferments faster and cooler dough slower. Neither is wrong, but the timings in a recipe assume a particular temperature. If your dough is several degrees cooler than the recipe's, expect bulk fermentation to take noticeably longer.

Measuring your friction factor

Mixing warms dough: a little by hand, more in a stand mixer. To find your own figure, mix a batch as usual, measure everything, then:

friction = (final dough temp × 4) − (room + flour + starter + water)

Example in °C: final dough 26, room 21, flour 21, starter 23, water 33 → 104 − 98 = 6 °C. Use that number next time you mix the same way. Gentle hand mixing is often close to zero.

Practical tips

• An instant-read probe thermometer is the easiest way to measure flour, starter and dough.
• If the formula asks for very hot water, for example above about 38–40 °C (100–104 °F), consider finding a warmer spot for bulk fermentation instead. You could also mix the water and flour first and add the starter afterwards, so hot water doesn't hit the starter directly.
• In a hot kitchen the formula may call for cold water. Fridge-cold water is fine. Ice counts as water by weight, but it takes time to melt.
• Keep the dough at its temperature during bulk fermentation. A dough that's mixed at the right temperature but left in a cold room will still drift down.

The same thinking applies to your levain build; see levain build ratios. To convert between scales: °C = (°F − 32) × 5/9, and °F = °C × 9/5 + 32. More conversions are in the grams to ounces chart.

FAQ

What is desired dough temperature in sourdough?

It's the temperature you want the dough to be right after mixing. Many sourdough recipes aim for roughly 24–26 °C (75–79 °F), because dough temperature strongly affects fermentation speed.

Why multiply by 4 for sourdough?

Four things set the mixed dough's temperature: room, flour, starter (preferment) and friction from mixing, plus the water you're solving for. Without a preferment there are three terms, so you multiply by 3.

Does the formula work in Celsius?

Yes, as long as every value, including the friction factor, is in the same scale. Convert a friction factor from °F to °C by multiplying by 5/9.

What friction factor should I use for hand mixing?

Gentle hand mixing usually adds very little, often 0–2 °C. Measure your own using the friction formula on this page, because mixers and methods differ.