The Fresh Loaf

A Community of Amateur Bakers and Artisan Bread Enthusiasts.

Water Temp Calculation using Friction Factor

rebudke's picture

Water Temp Calculation using Friction Factor

I've seen various sources that are using the following calculation to find the optimal water temperature:

Base Temp (DDT x 3 (or 4 in a preferment is used)) - Room Temp - Flour Temp - Preferment Temp (if used) - Friction Factor = Water Temp

My question is, do we need to take into account the amount of each factor being used? It seems strange that percentages aren't taken into account. 

RobynNZ's picture

Hi there

Like you I initially thought 'won't the variation in weight from the various ingredients in the different formulae I use affect the result?...'. The fact is when I check the temperature of the mixed dough, I've achieved the DDT. I suggest you just try the method and see how you get on. You may need to adjust the friction factor to suit your situation. Note, I find that  cold water from my tap (use rain water stored in a concrete tank) and the flour temperatures are generally similar ie kitchen room temperature. So in fact it is generally only the preferment temp that is making a difference anyway. (I blend any soaker with the levain and use the temperature of the combination. I add the levain at autolyse stage, add salt with a small amount of warm water later) I bulk ferment/proof in the hot water cylinder cupboard and switch the light on too. 

I do the calculation using the excel document on the Wild Yeast blog, which she developed from Jeffrey Hamelman's method. I switch my thermometer to °F (normally use °C) and thus stick with the friction factor of 5 for my hand mix. 

I like to know what temperature I am working with as it gives me a reasonable idea of timing across the day and fitting my own schedule around the dough, this is particularly so on the coldest and hottest days - no air-conditioning here.

Have fun figuring out what works for you!





WatertownNewbie's picture

I regularly use the formula, and for me the variable is the water temperature.  The flour will typically be close to the room temperature, and the preferment will be somewhere in that range, although sometimes a degree or two warmer.  To achieve the target dough temperature, I can vary the temperature of the water.

In the summer, when the flour, room, and preferment will be warmer, I need water that is cooler than in the winter, when everything else is often five or ten degrees colder.  Getting at or near the target dough temperature after the initial mixing is helpful in gauging the bulk fermentation process, especially when a sourdough is involved (and the rising will be slower than when instant dry yeast is the primary rising agent).

Apparently not many on TFL pay much attention to the target dough temperature, and it probably does matter more for commercial bakers (and not so much for a home baker like me), but I still find it very useful.

bikeprof's picture

That formula (to determine the water temp. to add) is widely used because it generally works.  But as with most things, particularly in baking, context matters, so we don't follow it blindly and wonder why it doesn't work in some particular cases.

Where you run into issues with it being off, following the reasoning that I think generated your question, is when you have a large amount of something that has a high heat capacity (i.e. water for a preferment or soaker) particularly when the temp. of that is very different from your DDT.  So when I make my multigrain, which has a big soaker of seeds and oats (thus lots of water), and that and my levain are pretty cold at mix time, I need to add water that is a bit above what the formula tells me (or let it go a bit longer in the mixer, letting the friction get the dough up to temp).  Interestingly (for me, a bread geek), that multigrain requires a longer mix to get the development I want, given all the stuff in that it usually works to use the same water temp as my other mixes for the day.

But in general, once you know your FF, I have found that standard formula to be incredibly robust...

WatertownNewbie's picture

Bikeprof, I have found that in the winter when things are cooler and if I am making a dough with a long (e.g., hour) autolyse, I typically up the water temperature by five or so degrees to compensate for the cooling that will occur during the autolyse.  Then when the salt and levain are added, and the dough is fully mixed, the dough temperature will be somewhat near the target.

I agree that adjustments need to be made when appropriate, and it is nice to hear someone else find benefit from the formula.