Fermentation/evaporation dough weight loss
Dear fellow bakers,
This question has been bothering me for years but now it's actually becoming crucial. I am a small-scale commercial baker baking to order for local health food stores, and this morning I, once again, found myself half a loaf's worth of dough short -- that means, one of my customers got 1 loaf less than they ordered, which is embarassing for me.
I always weigh all my ingredients very, very carefully, and it is quite impossible that I would've undermeasured anything by so much that I'd end up 150 g. short on a 500 g. loaf (the last in a batch of 17 ). There were some descrepancies between pre- and post- fermentation dough weights in other batches, too, but not nearly as drastic as this one. I can only assume that this is due to water evaporation during the overnight fermentation. As far as I can tell this loss gets higher when the temperatures climb, and is barely noticable when it's cold. I suspect that air humidity also plays a role but I'm not sure.
My question is this: provided my assumptions are correct, is there any sort of formula that could help me figure out the ratio of this loss depending on the variables, so that I could accommodate for it by mixing, say, 5% extra dough?
Of course, there's a chance that such a formula would be too complex for me to solve, and if that is the case I can always mix extra 10% just in case. Just thought I'd see if there's some way to get a bit more precise about it so I don't have to waste my nice expensive organic ingredients.
Thank you so much in advance for any ideas.