Perhaps this subject of baker’s percent has been written about so much that not one more ounce of ink needs to be spilled on the subject. But perhaps not. You still go into so many bakeries where the formulas are written out based on ‘gallons of water’ or there’s a notebook somewhere near the mixer where someone has, through trial and error, written down all of the relevant batch sizes, but with no way to scale them up or down.

One of the greatest things you can do for yourself is learn the metric system and baker’s percent methods. Once you’ve got your formulas (or recipes if you are at home) converted over to these two systems a whole world is opened up to. You can now scale up and down without any hassle. You can look at a formula and know if the dough is going to be stiff or wet. You can compare your formula to someone else’s and discuss the technical differences. And if they are measured out using metric units, so much the better because now all you have to do is move that decimal point around.

Ok, so how’s it done. It’s surprisingly simple. In your formula all the amounts of your ingredients are expressed as a percent of the total flour in the formula. Simple example: your formula calls for 10kg bread flour and 6kg of water (we’ll leave out the rest of the ingredients for now). Therefore your flour is 100% and your water is 60%. Got it? You might be tempted to think that you have 16kg of total ingredients and 6kg of water would be 37.5%. And you are right, but that doesn’t get you any of the added functionality that comes from baker’s percent. Applying the power of baker’s percent to our example: Let’s say you want to base your formula on 20kg of flour. Your formula calls for 60% water so you take 60% of 20kg and it gives you 12kg water.

Let’s look at a full formula. Here is one for pate fermentee:

The great thing here is you can compare our earlier unrealistic ‘dough’ with this one and notice differences, bearing in mind that with baker’s percent you are able to make ‘apples to apples’ comparisons. The first ‘dough’ had a 60% hydration whereas this one has 66%, a little wetter. You see the yeast at 2% which is very common for a yeasted dough (ie one using no natural leavening). In a finished dough you would tend to see the salt at around 2% as well, but this is pate fermentee which is dough taken from the previous mix prior to the addition of salt. For review: we got the 66% water by dividing the weight of the water by the weight of the total flour and multiplying by 100 to give us the percentage (66% in this case: 100kg of flour yields 66kg of water). Same for the yeast: 100kg of flour means you need 2kg of fresh yeast.

The next angle might be: what if you have two or more different types of flour in a formula. Maybe some bread flour and whole wheat flour combined. I think there are two schools of thought on this. The first being that anything other than white flour is just an ingredient and so you would express their amounts (ie the weight of the whole wheat flour) in terms of the white flour. I don’t like this method at all and it really does seem to be pretty rare that you run across this method. So say you have 10kg of white flour and 90 kg of whole wheat. That will give you really weird percentages and your water is well over 100%. It really does away with a lot of the simplicity inherent in baker’s percent.

The best way to express these mixed flour formulas is to total all of the flour and express that as 100%. Using the above example with the bread flour at 10kg and whole wheat 90kg your total flour weight would be 100kg (100%) and if you were using 70kg of water you would be at 70% hydration (sounds wet but there is a lot of whole wheat in there). And then of course your salt and yeast (and oil, and whatever else) would be based off 100kg.

Let’s keep stepping up the complexity. What happens when you have a preferment, like a sponge or a biga. Here is part of a formula:

There are two points to note here. The biga is treated as if it were a standalone formula with it’s flour serving as the 100% ingredient and all the other ingredients in the biga based off that weight. The other point to note is the biga in the final dough is treated just as if it were another ingredient based off the flour weight. This is handy because if you need to increase the size of the formula you can simply find out how much more biga you need (as a percentage) and then make more biga to meet that need.

I’ll leave you with a complicated formula to ponder but which follows all the rules we have seen so far:

Oh, but we can’t leave it right there. Remember that we said that one of the strengths of baker’s percent is being able to compare ‘apples to apples’ two formulas. Well when, you look at the final dough above you might be tempted to think that looks like an awfully dry dough at 53.8% hydration (water content). But don’t forget you have water contained in both the poolish and the levain. So at this point you can’t really get a good feel for this dough. Is it wet, dry? Is that enough yeast at 0.4%? Well, we have one last tool to introduce you to: the ‘overall formula’. I introduced this in an earlier post but basically the ‘overall formula’ adds together all the flour, water, yeast, salt, and any other ingredients and presents them with their combined weights and percentages.

It’s a little confusing to be certain. Basically the flour is a total of all the flour as listed in the levain, poolish, and final formula ingredient lists. Same for salt, yeast and water. The poolish and levain seem redundant since you have already accounted for their ingredients in the list. But, you must remember that the percentages and types of preferments in a dough is very important and changing those percentages will have a marketed affect on the dough. And that leads us into another topic: ‘total fermented flour’. But more on that later.