The Fresh Loaf

A Community of Amateur Bakers and Artisan Bread Enthusiasts.

Baker's percentage when using eggs

deblacksmith's picture
deblacksmith

Baker's percentage when using eggs

I am interested in how to handle eggs (whole) in determining the percentage of hydration in a dough.  This is what I have assumed.  Looking at information on eggs they appear to be approx. 25 percent solids and 75 liquid.  So I have assumed that by using 75 % of the weight of the eggs and adding it to the weight of water I can calculate a realistic percentage of hydration.  Is this correct?  Does it make sense?

Now how about the fat in a dough, I have assumed it is not part of the hydration.  Like wise I have assumed that Baker's dry milk is not part of the flour that you use to calculate the 100 percent.

I know at the end of the day the above is not important if the bread comes out the way you want and tastes good.  On the other hand I would like to be able to discuss these correctly when talking with others on TFL.

Dave

dolfs's picture
dolfs

Your assumption of using the egg's water content in the overall hydration calculation is correct. This is true not only of eggs, but for every substance you add that is in liquid form and contains noticeable amounts of water.

To aid with this calculation, and many other aspects of developing and scaling formulas, I've created the Dough Calculator Spreadsheet. Even if you decide not to use the spreadsheet, it contains a lookup table with hydration information for many common formula ingredients. I've used many sources to compile it, not in the least the USDA's nutrient database.

 

--dolf

proth5's picture
proth5

Seriously cool.  I've been thinking about incorporating the hydration percent for various items into my spreadsheet for awhile, but since I tend to use dry milk and make lean doughs it hasn't been a priority.

Just a question.  How do you use your spreadsheet to calculate t levain or preferment using a the percentage of the flour to be prefermented?

dolfs's picture
dolfs

In the Levains worksheet you will find some functionality for sourdough formulas. Principally these functions help you adapt formulas that use a different hydration starter than the one you have.

There is no function there for computing what you ask. I'll consider adding that to a future version. However, if you start with a non-sourdough recipe and you decide the percentage flour to be pre-fermented, things are straight forward. You know the hydration of your starter so the total weight of the starter you are going to use is total_flour_weight * percent_pre_ferment * (1 + starter_hydration). Don't forget to then subtract this flour (and water) from the yeast based formula to arrive at the amounts needed in the final dough.

deblacksmith's picture
deblacksmith

Dolf,

Thank you for the reply -- helps my understanding a great deal.  Great information in the spreadsheet.  I haven't played around with it any yet but in looks very complete and just the data section is very useful to me.

Again thanks,

Dave

dolfs's picture
dolfs

Keep in mind that the hydration data and specific gravity are constants and need no changes, but the prices of good are specific to where and how you shop, so if you care about price calculations, you should updated the prices, at least for those ingredients that you use.

jeb's picture
jeb

I have recently started playing with sourdough, so I don't have much experience with it. I have a 100% hydration sourdough starter that I've been developing over the past 3 weeks or so. When I've modified bread recipes that I've liked using yeast to try this starter, it is a wetter dough than the original recipe, even though the hydration is the same. Is there a rule of thumb to adjust for this difference?

Thanks for your help.

dolfs's picture
dolfs

While there is no specific function for that, the question was essentially asked above. I gave an answer there that should help you. The thing to keep in mind is that starters have had plenty of time to fully hydrate the flour involved (somewhat similar to what happens during autolyse). Things is though, that this should make the sourdough starter based version a little easier to mix and knead together.

Since you are seeing a wetter dough, I suspect you have not modified the recipe correctly. You need to take into account the amount of water provided as part of the starter and subtract that from the original amount of water in the original recipe. If you don't do that, or if your starter is actually of a higher hydration than you think (check your math), you'd end up with a wetter overall dough. If you have a converted formula, but your starter is not of the same hydration as the one used in the formula, you can use the "Levains" spreadsheet to adapt the formula for your starter. Using a different hydration starter, a different maturity, and a differently fed starter can affect the overall taste.

Is there a rule of thumb? No, but see above. There is a very precise calculation that you can (need to) do. If you do it right, hydration level will be the same. However, even a dough made with the exact same amounts of ingredients will "feel" different from day to day. This can happen because of different flours (sometimes even the same flour bought at different times can make the difference), different relative humidity etc. Additionally, since starters tend to become somewhat acidic, this can have an overall effect on dough properties, causing it to feel different (not necessarily a bad effect!).

So keep in mind that dough "feel", while generally correlated with hydration level, is not just determined by hydration level. Learn how your dough should feel for optimal results and then, as you put a final dough together, "feel" it, and adjust if necessary, adding water, or flour.

jeb's picture
jeb

I've taken 250 gm of a 100% starter, and subtracted 125 gm from each of the flour and water in the recipe. That's pretty simple math. I've checked my calculations.

I've made the original along side the modification, so the flour and humidity are controlled. The sourdough is "wetter". My starter is "wetter" after it has autolysed overnight, too, so why wouldn't a recipe seem wetter when using this in the recipe? When I first feed my starter, it is thick and sticky, but after 24 hours, it's almost like cake batter and will pour. Why wouldn't it. You're having insoluble starches converted into soluble sugars and alcohol, so I'd expect it to become wetter.

I know that I can adjust by "feel", but I was hoping for a simple rule of thumb to make adjustments.

dolfs's picture
dolfs

Your math is correct. Your description of what happens to your starter describes a normal phenomenon (although technically it is not an autolyse). The main take away here is that flour takes time to hydrate, and overall feel changes in the process. I doubt, however (and I have no proof), that the conversion process you describe changes the hydration level. The soluble sugars are not water so do not change hydration. The alcohol is also not water, and some may evaporate, yet it is liquid, so it will contribute to a different feel. If you've ever made a formula using Reinhard's "epoxy method" you probably have noticed this very same effect. It is the main underlying principle for those kinds of formulas that have difficulty hydrating.

Your "side by side" comparison is not "fair" in the sense that there is no autolyse in the yeasted version. If you would mix the flour and water in that version and let it stand overnight before proceeding, you would get quite a different feel. In addition, the yeasted version will exhibit a different chemistry (different organisms, different metabolism), and some of the chemical by products, as you note, may affect feel. Finally, you mention that you are using 250g of flour in the starter portion. You do not mention the overall flour weight, but I am going to assume a single 500g portion. That would make your starter contribute half the (fully hydrated) flour. Many sourdoughs start with a much lower starter contribution (longer bulk ferment required) and your observed effect might not be as pronounced.

Based on all that, nobody will be able to give you a definitive "rule of thumb" to achieve identical feel. Since you are able, and willing, to make your breads side by side (at least a few times), you could easily determine your own "water correction factor". While it would be correct only for this particular formula, it could be a starting point for other formulas that use a similar hydration level and starter contribution. If you find you need 5% less water in the starter based version, just incorporate that as your own rule of thumb.

I have to say, though, in my own personal experience that to hydration is hydration, simply a calculated value, and not affected by chemical changes after the mix.  "Feel" is an entirely different matter, depending on much more than hydration alone. I generally control crumb structure by hydration level first, additives (if any) such as fats second, and process (shaping etc.) third. Work towards your desired outcome, keep track of what you are doing, and then you'll have it down, and repeatable, going forward.

jeb's picture
jeb

Actually, the 250 gm was the starter. Only 125 gm is the flour portion, since it is a 100% hydration.

I'll have to play with the water amounts to see what I come up with. I was hoping for a quick and easy rule so that I didn't have to figure out the amounts. It makes a difference in whether the dough is formable without any grief, or if it practically flows.