What is Bran? Here is the complete explanation

In our blog you can find a series of articles that illustrate the journey that wheat takes from the field in which it grows to its transformation into flour. We have described the properties of wheat, the selection and cleaning processes employed before milling, stone and roller milling techniques and finally the main characteristics of soft wheat flours.

We also talked at length about wholemeal and “00” flours, fresh pasta flours and the main milling machines.

In this post we want to take a “step back” and return to the origin of our journey, namely to the wheat itself, and describe it even more completely. It seemed to us that we have always looked at grain as we humans observe the Moon, that is to say, always looking at one side only, the one that gives us flour. Now we want to focus on the other side, which we could call “the dark side of the grain”. We are going to talk about bran!

Bran in a grain of wheat

We have already discussed this topic in a previous article on the characteristics and properties of soft wheat, where we specified that the bran constitutes approximately 14.5% of the caryopsis and is in turn formed by 7 overlapping fibre-rich layers, especially full of insoluble fibres, like cellulose and lignin. These fractions, together with the wheat germ, constitute the outermost layers of the grain. As we shall see in our next article, these are treated in a specific way by milling plants.

Bran or brans?

From the image above it is easy to see that there is not just one type of bran in the wheat grain, but many fractions, which, in the milling industry, are generically identified as “brans”. These are fine middlings, coarse middlings, fine bran and coarse bran, all products that are naturally present in the grain, and can be extracted, in whole or in part, with a roller mill, unless you want to produce wholemeal flour.

To explain these fractions (which are perhaps new to many readers of this article) simply, we can say that overall they constitute approximately 23-25% of the produce obtained by the milling of soft wheat and that, moving from fine middlings to coarse bran, their grain size, ash and fibre content increase, while their starch content decreases.

So, when we about broadleaf bran, we are not talking about a particular species of bran, but about a part of the bran itself which, as you can see in the figure above, is the product with the largest grain size and is extracted using a roller mill. To find out how bran is obtained in a mill, read our complete in-depth article.

Bran is also extracted by stone grinding. In this case the product consists of leaves with a finer, angular and irregular grain size, as shown in the photo below.

This photo may also help you identify a wholemeal flour actually obtained by stone grinding, as we explained in our article dedicated to the comparison between stone-ground and roller-ground wholemeal flour.

Coarse and fine bran: the two most well-known brans

Coarse and fine bran are certainly the best-known bran fractions of the wheat grain, since, unlike fine and coarse middlings, they are used in many baked products such as biscuits and crackers.

Coarse and fine bran are made up of the outermost layers of the wheat grain, which are seven, and the aleurone layer. Coarse bran, together its more refined variant, fine bran, makes up about 14.5% of the wheat grain. They have very important nutritional values being rich in fibre, antioxidants and mineral salts such as phosphorus, potassium and magnesium, but also vitamin B3, lysine and phytic acid. To conclude our overview of bran, it should be pointed out that fine middlings are not of much interest from the point of view of human nutrition. They are usually extracted to be marketed as animal feed and are particularly suitable for raising young cattle thanks to its nutritional values which are rich in starch and proteins.

Coarse middlings, like fine ones, are mainly used in animal husbandry, but they are also used in various traditional Italian bread recipes, such as Lariano bread.

What is wheat germ and how is it used?

Our overview of the outer layers of the wheat grain is not over yet, we still have to look at the wheat germ (or embryo), which represents about 2 – 3% of the total weight of the caryopsis. Although it is present in very small percentages, the germ may be considered a real “mine” of nutrients, as it offers a significant dose of essential unsaturated fatty acids, vitamins, minerals and proteins.

Precisely because it is present in such small percentages in the wheat grain, it is particularly interesting to be able to have pure wheat germ, made possible by the extraction capabilities of the roller mill. When it is pure it is possible to use this tasty ingredient as a natural food supplement, to add to dough or to eat together with other foodstuffs such as yogurt or soups. But be careful, wheat germ goes rancid in just a few days, making this precious fraction of the grain almost impossible to use! To overcome this limitation, we at Mulino Padano have created the StabilEasy method, based on the totally natural use of steam, and used it to produce our GranEssere Wheat Germ, which combines long shelf life with a strong aroma and innate nutritional values.

Why stabilize wheat germ and bran with steam?

Wheat germ and, to a lesser extent, bran, are characterized by a high percentage of fatty acids and enzymes such as lipases. These components are responsible for two disadvantages:

• they lead to the rapid oxidation and rancidity of both the flour and the baked produce obtained from it;
• they weigh down the dough, leading to poorly developed bread with a very moist crumb.

Because of these two disadvantages, both wheat germ and pure bran find little use in baking, patisserie or pizza making, which is a real shame as these ingredients are an excellent source of fibre and essential nutrients.

To overcome these limitations, we have created the StabilEasy – Natural Steam Stabilization method which, after the cleaning of the wheat, subjects the milled produce to steam cooking at a controlled temperature and humidity. This natural “steam stabilization” overcomes the limitations of the short shelf life of these products, preserving their nutritional values and also providing the following additional advantages:

• increased healthiness, thanks to the action of the steam which reduces the amount of bacteria contained in the outer layers of the wheat’s caryopsis;
• a pleasant taste and distinct aroma, free from the bitterness that normally characterises fibre-rich products;
• greater ease of use and dough management thanks to the inhibition of enzymatic processes that hinder the proofing process.

Bran and what surrounds it: let’s recap

In this article we have gone back to the beginning looking at the wheat grain from a new point of view, diametrically opposed to the most widespread one. We have looked at the grain from the bran’s viewpoint. We have taken the opportunity to clarify that:

• There is not just one type of bran, which is why it is better to talk about fine and coarse middlings and fine and coarse brans. Overall, brans constitute 23-25% of the grain.
• Coarse bran, together its more refined variant, fine bran, makes up about 14.5% of the caryopsis.
• In addition to these products, among the outermost fractions, there is also wheat germ, which is a “mine” of nutrients and represents 2-3% of the grain.
• Brans and wheat germ are very rich in fibre, vitamins and fatty acids. This makes them precious from a nutritional point of view, but almost impossible to work in their pure form because of their very short shelf life. To overcome this limitation we have created the StabilEasy – Natural Steam Stabilization method.