There are quick breads and yeast breads. Quick breads use baking powder or soda, which generate carbon dioxide much faster than yeast. In this category we include cakes and delicate pastries.
There are two kinds of wheat, soft and hard. Hard wheat has more protein and can hold its shape better; i.e. it is ideal for keeping pockets available for slow rising yeast breads to fill in. Soft wheat doesn't hold its shape as well but responds better to quick rising agents, those used in cakes and pastries. If you try to make bread with soft wheat only, it will not rise as well since the structure is less rigid and will be less apt to maintain its shape and hold in the carbon dixode until the bread has set.
All purpose flour is a mixture of soft and hard wheat. Bread flour is a blend of all hard wheat. All purpose flour is less ideal than bread flour for making yeast breads, as you might have guessed. I read a note from "Chef Joan", who combines both types in her recipe, saying that the all purpose flour absorbs more liquid and therefore result in a fluffy light texture. The bread flour has more gluten which gives the dough elasticity and makes it more dense. hmmm...trying to balance out these factors....
Another factor is not only the type of wheat (soft vs hard) but also the refinement. Whole wheat flours contain the entire wheat berry, including the germ and bran. Highly refined flours (among them your standard enriched all purpose flour) do not.
An interesting attribute of whole wheat is that it absorbs more water per volume than highly refined flour.
The factor I am particularily interested in is why Rachel's sticky buns were dense and cement like when she substituted whole wheat for all purpose flour. Was it due to the soft/hard property of the wheat? I believe it's possible to buy a whole wheat flour made entirely of soft wheat. Perhaps she needed to add more water to meet the absorption requirements of the whole wheat? Or were her hockey pucks due to some other property of whole wheat flour and the effect of the wheat berry on the glutinous dough structure?
The starch content of the flour also matters. Starch is a carb that makes up about 70% of the flour by weight. It releases sugars into the dough on which the yeast feeds. It also reinforces gluten and absorbs water helping the gluten hold in those gas bubbles.
This is yet to be resolved, but fascinating stuff.
Note: white whole wheat flour rises higher, making it lighter and milder in taste (more like enriched white flour) than the traditional whole wheat flour, which is made from hard red wheat.
Note 2: Durum wheat is super hard, making it appropriate for pasta and egg noodles.
Some Answers
Whole wheat flour has less gluten making proteins and less starch due to the presence of that other good stuff, germ and bran. These might comfort us in the pursuit of good health, but also can limit our palatial pleasure in the bread department. Why?
Point 1: Gluten is an elastic compound formed by the lining up of key proteins that lends structure to bread. Less gluten means less structural integrity which means less rising which means if you just substitute whole wheat for all purpose flour, you'll get denser, smaller loaves
Point 2: Bran is sharp and cuts gluten fibers as the dough rises, further reducing the structural integrity of the bread. Whole wheat flour contains bran, all purpose does not.
Point 3: Whole wheat flour absorbs significantly more water than all purpose flour.
Point 4: Whole wheat flour contains less starch than all purpose flour. The starch in flour is broken down by enzymes from the proteins to coax out sugars which will feed the yeast. If the yeast is not fed enough, it will not poo out enough carbon dioxide to sufficiently push out the gluten web you so lovingly prepared earlier.
This is all sounding quite discouraging to those of us who desire healthy colons and fluffy snacky bread. However, we can counter some of these properties of whole wheat flour.
Response 1: The easy and most common answer to countering lower gluten making ability of whole wheat flour is to replace some of it with all purpose flour. I've read suggestions to replace anywhere from 66% to 80%. Another idea is to add some extra vital wheat gluten or gluten flour to help form those glutenous strands.
I would personally suggest using bread flour in lieu of all purpose. This is because bread flour is made from all hard wheat, which produces more gluten than all purpose flour, which is a blend of hard and soft wheat.
Finally, kneading bread is what makes gooey gooey dough into a marvelous glutenous strong-like-bull mass. Kneading is what aligns those elastic fibers and makes them most strong and cohesive.
So if you are using the part whole wheat/part all purpose or bread flour method, I would try starting the mixing and kneading process with the all purpose or bread flour, then adding in the whole wheat flour afterwards. And whatever order you add it, kneading extra long will help maximize the formation of the proteins into gluten.
Note that many whole wheat flours already contain some all purpose flour.
Response 2: Use the finest grind of whole wheat flour to reduce the occurrence of sharp bran edges. I also read a suggestion to NOT permit the dough to rise to double, because that's when those mischievous little scissors are most at work.
Response 3: Be very guarded about the amount of whole wheat flour you use, or add more water. In my experience, bread dough should be really very gooey when you start kneading it. As the gluten fibers align, it will 'un-goo', since now the fibers are attracted to each other rather than your hands. (I do notice that the attraction to my mouth never really subsides though.)
Response 4: To coax out as much starch as possible from the whole wheat flour, permit a long fermentation time for the yeast.
Peter Reinhart describes the starch molecule as a tight ball of yarn, saying "when we taste raw flour, or even raw bread dough, very little flavor is perceived by the palate because all the threads are wrapped around one another, making them difficult to discern. Flour tastes like sawdust because its sugar components are too complex to differentiate on the tongue. Now, introduce a catalyst, an enzyme, that acts like a wedge breaking apart that ball of yarn, freeing the various threads so that they become accessible ("The Bread Baker's Apprentice," p. 62). All those enzymes in the flour and the yeast need time to do their tasty work.
Time is most commonly achieved by refrigeration, often overnight. You might also allow an extra rising to coax out a little more sugar. Another common method is to use a sponge which might be wet and gooey, bread like or come in other forms. All these involve the same process though: you combine part of the ingredients ahead of time and let them hang out together, then add the rest of the ingredients and proceed with your breadmaking. An example would be to mix some of the flour, yeast and water together and allow to stand overnight. Add the remaining ingredients the following day to make bread as usual.
It is important when using a sponge to use a little less yeast in inverse proportion to the amount of time the sponge sits out. "You only need enough to make the sponge bubble and rise slightly to stretch the gluten; you don't want the yeast to eat all the broken-out sugars, shit out a bunch of ethanol, and then starve to eath...although that would be totally punk rock."
Some other considerations include:
- Use walnut oil to give dough more softness and moisture. Almost any fat will help the loft somewhat.
- The biggest benefit to white whole wheat flour over traditional red whole wheat flour is color and taste. The taste is much sweeter since there are fewer tannins in wheat berry.
- Freshly ground berries will have no rancidity or bitterness whatsoever, and keeps the dough lighter than pre-ground whole wheat flour.
Reference: Help from Swanky Gruel and other googled sources
