Search

Wheat bran separated in the standard milling process as a by-product contains many substances of importance in livestock and human nutrition. In the Czech Republic, as in other Central European countries, a significant part of the bran is not traditionally used as a raw material for feed production and is used as a heating fuel. This means that many interesting and health-promoting components of fiber, phenolic compounds, vitamins, proteins, and minerals are lost. The bran is made up of particles of the grain outer coating and sub-coating layers, particularly the pericarp, testa, and aleurone layer. Their composition varies, but while the pericarp in particular is largely composed of cellulose and lignin, the testa and aleurone layer contain many valuable non-starch polysaccharides (hemicelluloses), as well as the macro- and micronutrients mentioned above. Wholemeal flours contain all the anatomical parts of the grain mentioned above, which brings both technological problems in terms of their bakery processing and a not always acceptable sensory impact on the products. This paper summarizes selected physical and physicochemical methods that can be used to remove those components that may cause technological and sensory problems and retain those that, on the other hand, represent a significant nutritional benefit.

Common bakery and many other cereal products are characterised by high glycaemic index values. Given the increasing number of people suffering from type 2 diabetes at a very young age, technological approaches to reduce the glycaemic index of cereal products are extremely important. In addition to increasing the dietary fibre content, either by using wholemeal flours or flours with added fibre from other sources, practices leading to an increase in resistant starch content are also of great interest. This review summarises the most important technological processes used to reduce the glycaemic index of bread and other bakery products. The summarization shows that the potential of various technological processes or their physical and physicochemical modifications to reduce the glycaemic index of common bakery products exists. At the same time, however, it has been shown that these processes have not been sufficiently explored, let alone applied in production practice.

Wholemeal flours from various cereals and pseudocereals are a valuable source of nutritionally important fiber components, especially beta-glucans and arabinoxylans, as well as bioactive substances accompanying dietary fiber. Most types of whole-wheat flours have unfavorable baking and sensory properties. The finest granulation of bran particles in the flour has a significant effect on reducing or eliminating these deficiencies. Special disintegration equipment is required to achieve fine granulation of the bran particles. In this study, we have tested a special type of impact mill (originally intended for grinding of plastics) to produce special finely ground wholemeal flours with lower starch damage and higher farinographic absorption. Moisture content in the studied flours was significantly lower (7.4–9.8%) than is common in standard flour (13–14%). According to the results of flour analyses obtained from several cereal sources, it seems that especially in rye and wheat, this technology is suitable for both achieving fine granulation of bran particles and in terms of not very substantial damage of starch granules.