This gets to the science behind baking bread. If you can make an excellent loaf of bread that turns out exactly as you want it to without knowing anything about bread hydration and baker’s percentages, great! Me? Not so much.
I started reading up on it preciesely because my bread wasn’t turning out the way I thought it should or the way I wanted to, and I figure that the best way to get my bread to turn out how I want is to learn more about the science behind it all.
Bakers percentages first.
Professional bakers express their recipes as formulas. The amount of flour always adds up to 100% and the remaining ingredients are a percentage of the total flour, and it’s always by weight, not volume. I’ll use a French bread formula as an example:
In this case, the hydration of the dough is 60% since that’s the percentage of water in the formula.
Another thing about the formula. Because it’s expressed as a percentage, it can be easily and quickly converted to any amount of dough – 1 pound, 10 kg, 150 pounds, 675 grams, and so on.
Here’s another example:
|White flour||650 grams||65%|
|Wheat flour||250 grams||25%|
|Sourdough starter (100% hydration, so 100 grams flour + 100 grams water)||200 grams||10%||10%|
The sourdough starter has a hydration level of 100%, meaning that the water amount is 100% of the flour amount. That means that for every 100 grams of water in the sourdough starter, there is 100 grams of flour. Or 10 ounces of water and 10 ounces of flour. Personally, I keep my sourdough starter at 100% hydration for two reasons: one, it’s easy math if I need to convert or modify a recipe, and two, it’s easy to manage – not too thick, not too thin.
This bread has a total of 1000 grams of flour, including the flour that’s in the sourdough starter. The water amount, including the water in the sourdough starter, is 65% of the flour weight, giving this bread 65% hydration.
There are other ways of showing a baker’s formula, but I won’t go into that here. If you want to read more and totally geek out about this stuff, get Peter Reinhart’s A Bread Baker’s Apprentice.
I mentioned hydration earlier.
Hydration is a measure of how wet the dough is:
- Stiff & Dry- 58 to 60% water content
- Firm & Tight – 60 to 62%
- Modestly Firm – 62 to 63%
- Malleable – 63 to 64%
- Soft – 64 to 65%
- Slack – 65 to 67%
Please note that that’s water content. Oil or other fats don’t count towards hydration.
American style breads usually are about 60 to 62% hydration, French style breads between 62 to 65%, and Italian style (ciabatta) breads upwards of a 68% range.
I calculated Peter Reinhart’s bagel recipe – converted to grams, so there may be rounding differences – to be around 52% hydration. In kneading it, it required zero added flour and did not stick to anything – not my counter, not my hands, nothing. I knew this was likely the case walking in because I’d calculated the hydration levels first.
Another recipe I’ve made I calculated the hydration levels as 65-67% but the recipe had a description that the dough should be tacky, not sticky. I already know that 65-67% will definitely be sticky (this could also be because of my heat and humidity levels), so I wasn’t surprised that a whole bunch more flour was added before the proper description of feel was achieved. My ending hydration levels were closer to the 58% hydration level.
About humidity – I live in the tropics and we’re currently in monsoon season (we have two). That means that the humidity levels here are significantly higher. Since flour and other ingredients can absorb water from the air around us, I may need higher amounts of flour/less liquids in a recipe to achieve the exact same feel in the dough as compared to someone from, say, Edmonton, Alberta, or Phoenix, Arizona. So if you tell me that you make the exact same recipe as me, but your hydration levels are different than mine even though ours turned out the same, I’m okay with that. And I would expect that. And this is all on top of different flours absorbing different amounts of water differently.
And that’s something else that calculating hydration levels and the dough formula does for me – it tells me what to expect from the dough. Is the description for the dough saying it should be firm and tight but the calculated hydration levels tell me soft, or vice versa? I already have a clue, right there, that the amount of flour or water used will have to be altered.
In the end, when making bread, I record the ending flour amounts I actually used so that, next time, I can start out a whole lot closer so I don’t have to do as much jimmying with the recipe each time. It’s easier for me and it’s easier to get more predictable results from my bread. And, to me, that’s what baker’s percentages and hydration levels do for me – they allow me to get predictable results.
[pg-image src="http://pics.laurieashton.com/tn/20090522-18.jpg" link="http://album.laurieashton.com/v/SriLanka/kitchen/20090522-18.jpg.html" caption="bread dough, 67 percent hydration" alt=""] [pg-image src="http://pics.laurieashton.com/tn/20090522-20.jpg" link="http://album.laurieashton.com/v/SriLanka/kitchen/20090522-20.jpg.html" caption="bread dough, 54 percent hydration" alt=""]