Cheese Makers Forum FAQ Equipment part 1 Equipment part 2 History

Monday, May 17, 2010

Baking Bread

I was talking to members of a yoyo forum I moderate (I don't yoyo, I just do sysadmin stuff for http://www.onedropyoyos.com ), and I realized some of the info there should be posted over here. So, here is some insights into baking bread I recently shared with the denizens of that web zone.

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Q. Where do I proof bread? Should I proof in a very low temperature over?
I've tried the 'oven proof box', doesn't work so hot--cause it get's waaay too hot :)
Instead, do this: go buy some large black trash bags. Place the bowl with your dough in the bags. Blow them up like a balloon, and tie them off. Place in a south facing window, and violin! Perfect proof box.

Q. Should I practice one certain recipe, or just try lots of different ones?
Practice, practice, practice. Use this recipe as your 'master recipe', it is a standard french bread recipe.

* 500 grams white flour (four cups flour minus two or three tablespoons)
* 300 grams water (1 1/3 cups water)
* 12 grams Mortons iodized salt (1 1/2 teaspoons it looks like)
* 5 grams yeast (3/4 of the content of one of the yeast packets)
* Olive oil for your hands

Add the yeast to your 300 grams of 86F water (yes, I did give you permission to buy a nice digital thermometer :D), and let it sit for 15 minutes. This is re-hydrating the dried yeast. They don't need any food yet--i.e. sugar--since they will get plenty in the dough.

Mix all the ingredients together with a spoon until mostly incorporated, then coat your hands lightly with oil. I actually prefer grapeseed oil, but use whatever you got. Using your hands, stretch and fold the dough like taffy. In fact, what kneading does is almost precisely what a taffy machine, yet less efficiently. Stretch and fold. Add oil to hands as needed. Stretch and fold. Do this for five minutes while contemplating something Japanese :)

Let the dough rise in the plastic bag for at least an hour and a half. Two and a half hours might actually be better, but don't worry if you can't.

No this next part is just hard to explain, I wish I had pictures, but it is the shaping and proofing step. Line a bowl large enough to hold the dough with cotton/linen/muslin and flour it. Not a ton of flour, we just don't want it to stick. Take your dough, shape it into a ball, then attempt to pull and squeeze one end to create surface tension in the dough. Pinch the end you are squeezing to seal it, and place the dough in the bowl with that pinched side up. That will become the bottom of the loaf. Proof for another hour and thirty minutes, and preheat your oven as hot as it will go.

When the proofing is done, flip the loaf onto a baking sheet with a small amount of flour/corn meal/semolina, use a sharp knife to deeply score the top, and put it in the oven. Turn the heat down to 475F, and bake for 50 minutes to an hour, or until your shiny new thermometer reads 200F in the center of the loaf.

Remove from oven, let cool for two hours on a rack, and enjoy with honey, butter, and/or a good vinegar.



Thoughts on Technical Baking

So, not to get too technical, but baking bread has three fundamental processes that are taking place, and I think that by understanding them you can have a greater insight into making great bread.

The first is starch to sugar conversion.

Experiment #1:
taste a slurry of white flour in water, then taste a small amount of the crumb of a french loaf. What do you taste that is different? What are the actual flavors? Well, with the white flour you taste almost nothing, since your tongue doesn't have taste receptors for the starch in the flour. The bread will have a sweet, filling flavor because during the baking process two enzymes have broken the starch into small molecules which we can taste. These two enzymes are called alpha and beta amalayse.

Experiment #2: Take a slurry of water and flour (about equal weights of each), and bring them to 148F for 90 minutes. Then taste the slurry. You will immediately notice that unlike the dry, ashy flavor that the slurry originally had, it has turned quite sweet. In fact during some of my measurements I saw an 8x increase in the amount of sugar in the slurry. This technique is basically a 'fast forward' of the entire baking process--the same thing happens during the rise and proofing, just much slower.

So why do we want this conversion of starch to sugar? Two reasons actually--flavor being the first, and creating food for yeast is the second. Yeast can't eat starch either, so to feed them this reaction needs to take place. Just so turns out that the temperature that yeast love to thrive in is also conducive to this conversion process (~80F), but it also happens differently at other temperatures. This is why you see so many different techniques, each one converts the starch in a slightly different way giving you a different flavor.


Number two, leavening.

Flour has two main components, starch and a protein called gluten.

Experiment #1: remove the starch from flour. This is actually pretty easy to do, and is used to make seitan. Take some dough, and run a thin stream of cold water over it. Gluten isn't water soluble, so eventually if you have enough patience, you will be left with just gluten. It feels kinda like rubber, and it is responsible for 'brick loaves'. If the starch and gluten don't have enough air/CO2 dissolved in the dough, it will bake so hard that it'll be inedible.

So, to inject CO2, we add yeast. Yes, this is the point of yeast.

By feeding yeast sugar (by breaking down starch) we inject CO2 into the dough. The gluten allows the dough to stretch kinda like rubber, keeping the CO2 from escaping. The holes in the crumb prevent the whole mass from being an anchor. So, it is in controlling the amount of CO2 in the dough, and also where it is being stored that gives us the difference between a smooth crumbed loaf and something like ciabatta.


The final process is the gelatinization of the dough (i.e. baking).

Four things happen during baking. First, the Maillard reaction caramelizes sugars in the crust, giving it a dark color and a rich full flavor. Second, heat causes the dissolved CO2 to expand, giving us holes in the crust. Third, the gluten gelatinizes an sets the final size of the loaf. And lastly the heat drives off moisture, preventing the remaining starch from being soggy.

Problems occur in baking when the final size gets set, but there is still CO2 that wants to expand (breadsplosions, as I call them); when the dissolved gas doesn't expand fast enough to prevent the dough from collapsing before gelatinization (flat loaves); and moisture isn't driven off fast enough to prevent dough collapsing (heat too low, or no bread stone). Some of these problems can be fixed by technique, some by changes to temperature, and some in the recipe.

For example, the reason we use steam or humidity in baking is to prevent the loaf from hitting it's final size too fast, so the CO2 can still expand. Otherwise, you either end up with loaves that rip themselves apart, or a crumb that is dense and unattractive.

The reason we use bread stones is that clay/rock/whatever transfers heat much more quickly than air, so the gas can expand faster than the crust is caramelizing. It's a race to get gelatinization, caramelization, and gas expansion completing at the correct time in relation to one another. And that's why we get neat, novel techniques like No Knead that to those who don't understand the science behind baking seems unintuitive, but to those who do understand makes perfect sense.

Happy Baking!!

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Cheese A Day by Jeremy Pickett is licensed under a Creative Commons Attribution-Noncommercial 3.0 United States License.
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