Summer Sourdough Crushed Ice & Water Temp Chart for a Hot 90 Degree (90°F / 32°C) Kitchen — Stand Mixer Knead 8-Min (78°F DDT)
4-factor Desired Dough Temperature (DDT) and 80 cal/g latent heat crushed-ice calculation for hitting 78°F dough in a hot 90°F room.
Heat flows in two directions in a 90°F (32.2°C) kitchen: heat flows from the 90°F flour and levain into the dough, and stand mixer knead 8-min (78°f ddt) adds +14°F of its own. To land the finished dough on 78°F, the 258g of liquid water must enter at 28°F (-2.2°C). Cooling from 78°F tap water down to 28°F means melting 92g of ice into the 350g batch and leaving 258g of liquid water; each gram of ice absorbs 80 cal on melting alone.
- Required Water Temp
- 28°F (-2.2°C)To hit 78°F DDT in 90°F room
- 350g Batch Ice Split
- 92g Ice / 258g WBased on 78°F tap water & 80 cal/g latent heat
- Mixer Friction Factor
- +14°FStand Mixer Knead 8-Min
- Target Final Dough Temp
- 78°F (25.6°C)Locks fermentation clock & protease rate
DDT Reference for 90°F Kitchens — Stand Mixer Knead 8-Min (78°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 |
|---|---|---|---|---|
| 400g water (90°F / +14°F) [Anchor] | 28°F (-2.2°C) | 105g crushed ice | 295g tap water (@ 78°F) | 78°F (25.6°C) final dough |
| 350g water (90°F / +14°F) Quarter Batch | 28°F (-2.2°C) | 92g crushed ice | 258g tap water (@ 78°F) | 78°F (25.6°C) final dough |
| 250g water (90°F / +14°F) Three-Quarter Batch | 28°F (-2.2°C) | 66g crushed ice | 184g tap water (@ 78°F) | 78°F (25.6°C) final dough |
| 500g water (90°F / +14°F) Half Batch | 28°F (-2.2°C) | 132g crushed ice | 368g tap water (@ 78°F) | 78°F (25.6°C) final dough |
| 300g water (90°F / +14°F) Double Batch | 28°F (-2.2°C) | 79g crushed ice | 221g tap water (@ 78°F) | 78°F (25.6°C) final dough |
Interactive Desired Dough Temp (DDT) & Ice Solver Calculator
Compare your exact mixing bowl dimensions, flour protein percentage, or discard weight in real time.
Baking Sourdough in a Hot 90°F Room: Why You Need 28°F Water (92g Ice)
Liquid water absorbs 1.0 cal/g per °C of warming, whereas solid ice at 0°C (32°F) absorbs 80 cal/g (144 BTU/lb) to melt into 0°C water before warming. That phase-change heat sink counteracts a 90°F (32.2 Celsius) room plus +14°F of stand mixer knead 8-min (78°f ddt) friction when the theoretical water temperature drops to 28°F.
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 Stand Mixer Knead 8-Min (78°F DDT) in a 90°F Room
- Probe Ingredients (90°F / 32.2 Celsius): Verify ambient room (90°F), flour, and starter temperatures with an instant-read probe thermometer before running Stand Mixer Knead 8-Min (78°F DDT).
- Weigh 92g Ice + 258g Tap Water: For 350g total water, combine 92g finely crushed ice with 258g (@ 78°F) tap water.
- Verify Final 78°F Dough Temp: Probe the dough center immediately after stand mixer knead 8-min (+14°F friction); it should read 78°F ± 1°F.
- Record the Reading: Write the actual temperature on your recipe card — in a 90°F (32.2 Celsius) room the next bake will need the same correction, not a fresh guess.
Frequently Asked Questions for This Desired Dough Temp (DDT) & Ice Solver Spec
How much ice do I add to 350g of bread water in a 90°F room (Stand Mixer Knead 8-Min (78°F DDT))?
Replace 92g of water with finely crushed ice and use 258g of 78°F tap water to hit 78°F DDT.
How accurate is the 28°F figure in practice?
Within about 1°F, provided the four inputs really are 90°F room, 90°F flour, 90°F levain and +14°F friction. Probe the finished dough to confirm and adjust your next bake.
Does humidity in a 90°F (32.2°C) kitchen change the water temperature?
Marginally. On a humid morning the dough surface loses less moisture and cools a little less, so half a degree less cold water is usually right. Treat it as a refinement, not a correction.