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The basis of making bread is simple. You knead flour + yeast + water, possibly with some salt, into a nice dough. You leave it to proof, might shape it along the way, and bake it. In some cases you can even skip the kneading and just mix the ingredients together and wait (such as when using a Loafnest).
But, you can also decide to make bread baking a complex endeavor. You can use all sorts of different flours, proofing techniques, sourdough starters, fancy shaping methodologies. The options are endless.
As soon as you step away from your one basic recipe though, your bread will behave differently and you’ll run into new challenges. It’s what happens to a lot of people when they switch from white flour to a fully whole wheat bread. All of a sudden, the bread comes out differently. But why? And what should you be looking out for?
What is whole wheat flour?
Wheat flours all start with whole wheat kernels. These wheat kernels consist of three major components: the bran, endosperm, and germ. The germ is what is the starting point of a new wheat plant if the kernel is planted again. The endosperm serves are food for this germ and contains food for it to grow (mostly starch). The outer layers, made up of bran and an aleurone layer, protect the inside. These outer layers contain a lot of fibers.
Wheat kernels need to be milled in order to use them for making bread. We describe milling in more detail here. For now, you need to know that during milling the wheat kernels are broken down into smaller pieces to create a fine flour.
It’s during the milling process what whole wheat flour and white flours are separated. Initially, the whole kernel is milled down into smaller particles. If you’re making whole wheat flour you’ll mill the kernel down until it’s fine enough. Since the outer layers are brown in colour, the resulting flour will also be brown, or whitish with clear brown speckles.
If you’re making a white flour (e.g. a regular bread flour) you also start by grinding this initial whole kernel. However, very quickly you’ll have to separate the endosperm from the rest. For white flour you only want this starch-rich fraction. White flour does not contain the bran and it’s that missing element that has such an impact on how your bread will turn out.
A note on vitamins & minerals
Depending on where you live, your white flours might contain a long list of vitamins and minerals. In the USA for instance this is required by law whereas in Europe this is not done. This is done to compensate for all the lost minerals and vitamins that are naturally present in the outer layers of the kernel. It’s also why whole wheat flour does not list them on the ingredient list. They’re in there, but haven’t been added separately!
Why is a whole wheat bread challenging to make?
So why does the presence of those outer layers in your flour make it harder to create a light and airy bread?
The gluten network
One reason is related to the formation of a gluten network. When you’re kneading a bread dough (or resting it for long periods of time) you create a network of gluten. Gluten are the proteins naturally present in wheat kernels. Both the endosperm and part of the outer layers contain this protein. The protein content of a whole wheat vs a white flour isn’t necessarily that different.
It isn’t the gluten content that is important here, it is how easy it is for those gluten to form that network. Adding fats but also adding things like nuts and seeds makes it harder for this network to form. Things like nuts and seeds cut through the network (which is why you knead the dough first before adding these in) and fat prevents the gluten from finding one another.
Those outer layer particles that are present in whole wheat flour can also ‘cut’ up the network. Especially if your flour is not as fine, this might make it more challenging.
But the outer layer is different in yet another way. It absorbs moisture more slowly and different than the finely milled starchy endosperm of the wheat kernels. This is because of the higher fiber content of the bran.
The fibers need more moisture to hydrate fully and they tend to take longer to fully hydrate. It is why it can pay off to leave a whole wheat bread dough to rest before kneading it fully.
Not all whole wheat flour is the same
Before looking into some specific whole wheat bread tips it is important to realize that not all whole wheat flours are the same. Even though all whole wheat flour is made from the entire wheat kernel, there still are considerable differences. Whole wheat flour by itself doesn’t fully describe a flour and how it works in your bread.
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First of all, different whole wheat flours can be made from different types of wheat. There are a lot of different types of wheat out there. A major difference between these can be their protein content. For making bread, you want a wheat type that contains a high protein content. The protein will create that desirable gluten network that you’re after when baking bread.
Wheat types can also differ in their hardness, which makes them either easier (if they’re hard) or harder (if they’re soft) to mill. Their color can even be slightly different as well as their flavor.
We discuss the different wheat types in a lot more extent here.
Fineness of grind
Even if millers start with the same grain, their final results can differ. An important factor is the fineness to which they grind. A miller can aim for a very fine flour with barely any larger particle left over. In order to achieve this they will likely have to mill several portions a few times to get rid of the last remaining chunks. On the other hand, the might also choose for a less fine grind, with larger particles left within.
Comparing three whole wheat flours
On the photo below you can see three examples of whole wheat flours. The two on the left are bread flours with a high protein content. Despite both of them being made for bread, their appearance is quite different. The sample on the left has a lot more larger particles left within the flour. You can even see parts of the outer bran.
The middle sample on the other hand is a lot smoother although pretty similar in colour to the left sample. The far right flour is the lightest of the three but very similar in fineness to the middle one. Looks deceive here though, it still is a whole wheat flour, but one with a low protein content, so not suitable for baking bread.
Troubleshooting a whole wheat bread recipe
If you want to convert your white flour bread recipe to a 100% whole wheat version, keep in mind the following.
- Use plenty of water: when making whole wheat bread you always need relatively more water than for regular white bread. The fibers and other complex carbohydrates absorb a lot more water. Start by adding +5% moisture and increase that depending on your dough consistency.
- Take your time: it’s best to start your bread by mixing the ingredients and leaving them for a little while (30 minutes should be good). This allows the flour to absorb water and makes it a lot easier to knead!
- Knead plenty: since the gluten network needs more time and energy to form.
- Choose a different flour: a finely ground flour is a lot easier to make into a delicious whole wheat bread than a less finely ground flour.
Good luck with this great bread and let me know how it went! If you want to understand the role of ingredients in bread better, have a look at my post dedicated on the topic.