Summer Sourdough Crushed Ice & Water Temp Chart for a Hot 84 Degree (84°F / 29°C) Kitchen — High-Friction Planetary Mixer (74°F DDT)
4-factor Desired Dough Temperature (DDT) and 80 cal/g latent heat crushed-ice calculation for hitting 74°F dough in a hot 84°F room.
Your mix water in a 84°F (28.9°C) room needs to sit at 20°F (-6.7°C) to finish at 74°F, provided the flour, levain and room are all 84°F and high-friction planetary mixer (74°f ddt) contributes +24°F of mechanical heat. The arithmetic is 4 × 74°F − (84 + 84 + 84 + 24) = 20°F. Since the required 20°F sits below the 78°F coming from your tap, swap 107g of the 350g water for finely crushed ice — the 80 cal/g phase change does the cooling — and keep 243g of faucet water alongside it.
- Required Water Temp
- 20°F (-6.7°C)To hit 74°F DDT in 84°F room
- 350g Batch Ice Split
- 107g Ice / 243g WBased on 78°F tap water & 80 cal/g latent heat
- Mixer Friction Factor
- +24°FHigh-Friction Planetary Mixer
- Target Final Dough Temp
- 74°F (23.3°C)Locks fermentation clock & protease rate
DDT Reference for 84°F Kitchens — High-Friction Planetary Mixer (74°F DDT) Water & Ice Split
Sums each row to the batch water weight so the split between ice and liquid always reconciles.
| Water Load | Theoretical Temp | Crushed Ice | Tap Water | Final Dough Temp |
|---|---|---|---|---|
| 350g recipe water — [350g Ref] | 20°F theoretical | 107g finely crushed | 243g from the tap at 78°F | final 74°F / 23.3°C |
| 400g recipe water — 100g Lighter | 20°F theoretical | 122g finely crushed | 278g from the tap at 78°F | final 74°F / 23.3°C |
| 300g recipe water — 100g Heavier | 20°F theoretical | 92g finely crushed | 208g from the tap at 78°F | final 74°F / 23.3°C |
| 500g recipe water — Half Batch | 20°F theoretical | 153g finely crushed | 347g from the tap at 78°F | final 74°F / 23.3°C |
| 250g recipe water — Large Batch | 20°F theoretical | 76g finely crushed | 174g from the tap at 78°F | final 74°F / 23.3°C |
Custom Batch Recalculation Engine
Fine-tune starter hydration between 50% stiff and 125% liquid while keeping your desired dough temp (ddt) & ice solver ratios locked.
Baking Sourdough in a Hot 84°F Room: Why You Need 20°F Water (107g Ice)
The 74°F (23.3°C) target is a fermentation-speed decision, not a texture preference. A dough that lands at 20°F mix temperature in a 84°F (28.9°C) room will ferment at the rate the microbiology model assumes, and the 24°F friction allowance for high-friction planetary mixer (74°f ddt) keeps the mixing heat from stealing that budget.
Timing the correction is part of the correction. Weight the ice before the flour goes in, and mix ice and flour together first rather than adding ice to a wet dough, because the 80 cal/g latent heat only works if the ice is in contact with the water before the starch starts to hydrate.
Thermal Control Protocol for High-Friction Planetary Mixer (74°F DDT) in a 84°F Room
- Measure the Room First: Confirm the kitchen really is 84°F (28.9°C) with a thermometer on the counter, not on the window, because radiant sun can read several degrees warmer than the working surface.
- Temper Flour and Levain: Bring both to 84°F before mixing. Cold flour is the most common reason a 74°F target is missed in a 84°F (28.9°C) kitchen.
- Combine 107g Crushed Ice with 243g Tap Water: Mix the ice into the 78°F water first and let it chill completely before it touches the flour.
- Mix and Check: After high-friction planetary mixer, probe the dough — it should read 74°F (±1°F) given the +24°F friction allowance.
Technical Q&A: Summer Sourdough Crushed Ice & Water Temp Chart
Why is my crumb gummy even though the dough looked the right temperature?
A correct 74°F dough can still bake badly if the core never reached 208°F. Check the internal temperature with a probe rather than trusting the oven dial, and remember to cool the loaf for two hours before slicing.
How accurate is the 20°F figure in practice?
Within about 1°F, provided the four inputs really are 84 degrees room, 84 degrees flour, 84 degrees levain and +24°F friction. Probe the finished dough to confirm and adjust your next bake.
Will the dough temperature change if I scale the recipe?
No. The 4-factor equation is a temperature balance, not a mass balance, so doubling the flour and water keeps the same 20°F target — but you must double the ice too, from 107g to 214g.