Fermentation and Proof Time vs Temperature

Q10 is the factor by which a biological rate changes for a 10 degree C change in temperature, and for baker's yeast in the range a bakery actually works in it is close to 2: warm the dough 10 C and it ferments twice as fast, cool it 10 C and it takes twice as long. Ten degrees C is 18 degrees F, which is why a 10 degree F miss on dough temperature is worth roughly 45% on the clock, large enough to blow a production schedule and small enough that it gets ignored. The relation is t = t_reference x Q10 ^ (delta C / 10), where delta C is the shortfall below the reference temperature. A bulk ferment that takes 2.0 hr at 78 F, on a morning when the dough comes off the mixer at 68 F, is 10 F or 5.56 C colder, so the ratio is 2 ^ 0.556 = 1.47 and the ferment runs 2.94 hr, nearly an hour late on a two-hour bulk. Run it the other way and at 88 F the same dough finishes in 1.36 hr, so a schedule built on 2 hours over-proofs it. Between 68 F and 88 F, an ordinary summer-versus-winter swing in an un-air-conditioned bakery, the same dough takes anywhere from 82 to 176 minutes. A scheduling estimate; the dough itself, judged by volume and the poke test, governs when it is ready.

delta_c = (reference_temp_f - actual_temp_f) x 5 / 9; ratio = q10 ^ (delta_c / 10); predicted_time_hr = reference_time_hr x ratio.

The Q10 temperature-coefficient rule applied to yeast fermentation, by name; a Q10 near 2.0 for baker's yeast in the working range is the value published in the standard baking-science references (Calvel, The Taste of Bread; AIB technical bulletins), cited not mirrored. The dough itself, judged by volume and the poke test, governs when it is ready.

The Q10 relation is public biology. The reference time and temperature are the bakery's own, and the Q10 value is exposed as an input rather than buried.

Estimate. AHJ and licensed professional govern.

Field names used by the API: reference_time_hr, reference_temp_f, actual_temp_f, q10, predicted_time_hr, ratio, delta_f, delta_c

• Q10 near 2 baker's yeast in the normal working range roughly doubles its rate per 10 C; the value is an exposed input, not a hidden constantbaking-science references (Calvel; AIB)
• 18 F per 10 C a 10 F miss on dough temperature is worth roughly 45% on the clockunit conversion applied to the Q10 rule