# Utilization of the Nutritional Potential of Wheat Bran Using Different Fractionation Techniques
## 6 Conclusions  
Wheat flours, or semolina, which are used for the production of bread and pastries, as well as pasta and many other traditional products, are predominantly produced in the standard milling process, which is aimed at extracting the endosperm as perfectly as possible and converting it to the desired granulation. The outer and sub-coat layers (pericarp, pericarp, hyaline layer, and to a large extent the aleurone layer) become part of the mill by-product (bran), which traditionally serves as a valuable ingredient in livestock feed. Nevertheless, in the event of a lack of sales to the animal feed industry, they are processed in a different way, often as a raw material for the production of alcohol or biogas, some of which is also used as fuel. The bran has considerable nutritional potential and is capable of adding very valuable fiber and other additives to cereal products. At the same time, the fiber is also able to partially compensate for the high energy value represented by starch in particular and also partially compensate for the associated high glycemic index of conventional bakery products and other foodstuffs. The easiest and most indirect route leading to the use of grain outer and sub-coat layers for human nutrition is the production and use of wholemal floors. It is known that these flours, due to their content of cellulose, lignin, and non-extractable hemicellulloses, complicate the technological properties of these flours and adversely affect the sensory properties of bread and bakery products or pasta. A way of partially eliminating these negative characteristics is to achieve very fine granulation of the lignocellulosic complexes, which cannot be achieved by standard milling processes but requires the use of special milling machines. Even so, there is always a risk of deeper damage to the starch granules, which is ultimately counterproductive both technologically and nutritionally. However, it is possible to significantly increase the fiber content and other nutritionally important substances found in the outer layers and, in particular, in the sub-coat layers, while reducing the negative impact on the technological and sensory properties, by means other than the production of wholemal flour. The first (and easier) way is by surface treatment of the grain in the form of peeling or partial debranning. In this way, significant separation of the technologically and sensorially unfavorable pericarp components from the remaining layers can be achieved. But its accuracy and efficiency are limited. In intensive peeling, even valuable parts of the sub-coat layers go into the by-products, whereas in a less intensive process, pericarp particles remain in the final product. Another, albeit less well studied and technically not yet easy, way is to take standard bran (bran from the standard milling process for wheat flour production), disintegrate it if necessary, and sort it into fractions according to the content of the components being targeted. The components rich in nutritionally important fiber components, and possibly other substances, can then be returned to the flours and the other fractions separated into a by-product or waste. There has not been much work published on this route, but the studies that have been performed suggest several possible principles that can enable effective fractionation to be achieved. As we have shown, these include physical procedures as well as physicochemical and biochemical ones. Some of these are clearly applicable to laboratory fractionations or to procedures directed to the isolation and preparation of certain substances from bran in special manufacturing. For wider use in mill production practice, which should aim at enriching flours not with preparations, but with not fully prepared but defined bran fractions, the combination of sieve sorting and airstream sorting seems most promising. The bran particles would then be sorted by size, and also by aerodynamic properties and specific gravity, after possible prior adjustment of the granulation.