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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.

Consumers are more interested in replacing commonly used chemical preservatives with natural substances. The effect of 5, 10, 20, 40, and 80 mg of thyme and lemongrass essential oils (THY and LMG, respectively) per 100 g of wheat flour was studied from the viewpoints of dough rheology, dough leavening progress, and the results of laboratory baking trial. Changes in dough viscoelastic properties were evaluated by the Mixolab rheometer and the company software. The higher the thyme oil portion, the higher the dough structure destruction by kneading and heat input in torque point C2, and consecutively shorter stability of dough consistency (up to one-half of the values recorded for the control); reversely, the LMG did not affect both features verifiably. In the 90 min leavening test, a dough weight loss was decelerated by both essential oils similarly. During the baking test, the average volume of wheat small breads as control was evaluated on level 167 mL (bread yield 451 mL/100 g flour). Independently of the dose of the THY or LMG, small bread volumes oscillated between 148–168 and 135–161 mL (average bread yields 442 and 443 mL/100 g flour, respectively). The shelf life of the products with a higher portion of essential oil was extended by up to 7 days.

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.

Fruiting bodies (basidiocarps) of the cultivated mushroom Pleurotus ostreatus (16 strains) were characterized by vibration spectroscopy and chemometrics. According to organic elemental analysis and Megazyme assay, the basidiocarps contained ~6.2–17.5% protein and ~18.8–58.2% total glucans. The neutral sugar analysis confirmed that glucose predominated in all the samples (~71.3–94.4 mol%). Fourier-transformed (FT) mid- and near-infrared (FT MIR, FT NIR) and FT Raman spectra of the basidiocarps were recorded, and the characteristic bands of proteins, glucans and chitin were assigned. The samples were discriminated based on principal component analysis (PCA) of the spectroscopic data in terms of biopolymeric composition. The partial least squares regression (PLSR) models based on first derivatives of the vibration spectra were obtained for the prediction of the macromolecular components, and the regression coefficients R2 and root mean square errors (RMSE) were calculated for the calibration (cal) of proteins (R2cal 0.981–0.994, RMSEcal ~0.3–0.5) and total glucans (R2cal 0.908–0.996, RMSEcal ~0.6–3.0). According to cross-validation (CV) diagnosis, the protein models were more precise and accurate (R2cv 0.901–0.970, RMSEcv ~0.6–1.1) than the corresponding total glucan models (R2cv 0.370–0.804, RMSEcv ~4.7–8.5) because of the wide structural diversity of these polysaccharides. Otherwise, the Raman band of phenylalanine ring breathing vibration at 1004 cm−1 was used for direct quantification of proteins in P. ostreatus basidiocarps (R ~0.953). This study showed that the combination of vibration spectroscopy with chemometrics is a powerful tool for the evaluation of culinary and medicinal mushrooms, and this approach can be proposed as an alternative to common analytical methods.