Lucie Jurkaninová

The conventional interpretation of mixolab curves that describe the behavior of wheat dough under mechanical and thermal stress was substantially extended by introducing a series of novel kinetic and geometrical descriptors. New indexes of Mechanical Weakening of Proteins (MWP), Thermo-Mechanical Weakening (TMW), and structural stability traits torque C12-to-dough stability ratio, slopes delta° and omega°, micro-scaled torque change rates (ΔmCji), and Structural Recovery Index C5/C1 were developed. The framework was applied to investigate the effects of four chemically distinct essential oils (from cinnamon, oregano, lemongrass, or thyme) incorporated into wheat flour at five concentration levels (5–80 mg·100 g⁻¹ flour). Based on the definition of the torque point C1, the selected parameters were converted into traditional Brabender units for practical industrial comparison with the farinograph records. Variance Components Analysis (VCA) was newly utilized as an advanced mathematical filter to select the most dough composition-dependent variables (to reduce ‘doubled parameters’ in data) prior to Principal Component Analysis (PCA). Standard parameters revealed that cinnamon and oregano oils significantly weakened the gluten network, whereas lemongrass oil preserved the thermomechanical stability of the protein. On the contrary, oregano and thyme oils promoted starch retrogradation, enhancing the rigidity of the cooled gel. Innovative descriptors successfully decoupled overlapping thermomechanical events, differentiating whether matrix damage was driven by mechanical shear or thermal stress. The integrated VCA-PCA approach effectively condensed 72% of the total experimental variance into a parsimonious two-component space while reducing the residual variance to just 6%. These findings demonstrate that the proposed kinetic descriptors substantially enhance the interpretative capacity of dough rheology profiling for functional bakery formulations.

The conventional interpretation of Mixolab curves describing wheat dough behavior under simultaneous mechanical and thermal stress was substantially extended by introducing a series of novel kinetic and geometrical descriptors. In addition to the standard Mixolab parameters, new indexes of Mechanical Weakening of Proteins (MWP), Thermo-Mechanical Weakening of Proteins (TMW), several traits aiming at stability of dough consistency (STA_{C1 rel}, C12/STA_C1), Structural Recovery Index (C5/C1), micro-scaled torque change rates (ΔmCij) and physical angular descriptors (slopes omega°, delta°) were developed to characterize individual phases of viscoelastic dough transformation to the solidified bread crumb-like material. The approach was applied to investigate the effects of four chemically distinct essential oils (EOs), namely cinnamon, oregano, lemongrass, and thyme ones, incorporated into wheat flour at five concentration levels (5–80 mg · 100 g^–1 flour). Besides those all innovations, selected standard Mixolab torque-parameters were informatively recalculated to the Brabender units—to be easily compared to the Farinograph proof results, because this rheological test represents the standard in the cereal chemistry and technology branch. Adaptation of the Principal Components Analysis lies in: i) using of the Variance Components Analysis in a role of the input data filter and ii) unfolding of the 3D-space to 2D-surfaces pair of plots along the shared PC2 coordinate. Conventional Mixolab parameters revealed that cinnamon and oregano oils significantly weakened the gluten network, reducing dough stability and lowering the minimum protein-related torque C2, whereas lemongrass oil preserved the protein stability at levels comparable to the control flour. Oregano and thyme oils significantly increased the final torque C5, indicating enhanced starch retrogradation and formation of a firmer structure of the cooled gel. The innovative descriptors provided substantially deeper insight into these transformations. Cinnamon oil generated the highest MWP values (up to 18.5 %), indicating pronounced mechanically induced gluten weakening. In contrast, lemongrass oil maintained MWP values close to the control while accelerating starch gelatinization and hot-gel breakdown, reflected by elevated beta° values and steepened gamma° slopes. Oregano and thyme oils reduced the gelatinization kinetics but markedly supported the retrogradation-related parameters, including C54, slope delta°, and the C5/C1 ratio, indicating enhanced structural recovery during cooling. Correlation analysis confirmed that the innovative descriptors captured complementary information and exhibited substantially lower redundancy than conventional Mixolab variables. Before Principal Components Analysis from 34 variables in total, Variance Components Analysis identified 17 representative parameters with the highest distinguishing power; Principal Component Analysis demonstrated two-component model of PC1 and PC2 explained 72% of total experimental variability and reduced data noise to only 6 % (per contra to 61% and 14%, respectively, in the case of the standard Mixolab parameters). The multivariate models clearly differentiated essential oils according to their chemical composition and dose-dependent rheological effects on water-dough behavior. The results demonstrated chemically distinct essential oils influence on wheat dough rheology through different mechanisms affecting protein weakening, starch gelatinization, hot-gel stability, and starch retrogradation. The proposed kinetic and geometrical descriptors substantially enhance the interpretive capacity of Mixolab analysis and provide a valuable tool for mechanistic–kinetic investigation of functional ingredients in cereal-based systems.

Recent trends in cereal chemistry emphasize sustainable food systems and functional fortification through upcycling and gluten reduction. This study addresses the challenges of reformulating wheat bakery products with four technologically distinct oat forms at three levels (5, 10, 15% substitution of wheat flour) by focusing on dough’s structural integrity. While conventional farinographic metrics such as Stability (STA) or Degree of Dough Softening (DSD) usually are not able to capture the dynamic fatigue of the gluten–starch matrix of wheat dough, several innovative kinetic descriptors are introduced, e.g., dough development slope angle (DDSA), and the time-resolved of both the dough curve width (DW) and farinograph elasticity loss (FEL) foursomes. Analytical results revealed that fiber-rich oat bran induced a mechanical ‘pseudostabilization’, whereas germinated diastatic malt caused a severe enzymatically driven structural collapse of wheat dough cohesiveness. This degradation was corroborated by a sharp non-linear decline in Falling Number (from 482 s to 196 s) and by a dramatic rise in the DSD/STA ratio (from 6.4 to 149.2). Statistical analysis indicated the proposed descriptors, particularly late-stage DW₁₅–DW₂₀ and FEL₁₅–FEL₂₀, provided more sensitive associations with quality parameters of small round breads baked at a laboratory scale—height, bread slice area, and specific volume—than traditional static indicators of the farinogram. As usual in such cases, a critical threshold of wheat flour substitution was identified at 10–15%. These results demonstrate that time–resolved kinetic modeling of dough elasticity serves as a robust complementary tool for predicting baking performance, enabling the rational optimization of formulations and the prevention of structural defects in industrial production.

Wheat is a major staple crop, and interest in its organic cultivation is growing. This study aimed to compare the technological and nutritional quality of winter wheat grown in organic and conventional systems. Sixteen varieties were evaluated using standard flour quality traits and ¹H NMR profiling of protein amino acids and free metabolites in whole-grain flour and water crackers. Organic wheat had lower protein and gluten but higher starch and gluten index, with most parameters remaining within acceptable bread-making ranges. Protein amino acid composition was largely similar, with a consistent trend toward higher lysine in organic samples. Organic flour contained less free asparagine and several other amino acids, indicating a reduced potential for acrylamide formation. Water crackers from organic wheat exhibited higher concentrations of prebiotic oligosaccharides, particularly stachyose (28.3%) and raffinose (16.2%), revealing nutritional benefits that emerge during baking. Additionally, we highlight the role of ¹H NMR metabolomics in food quality discoveries.

Oats (Avena sativa L.) are a rich source of β-d-glucans, dietary fibre, proteins, and lipids. However, the behaviour of these components in wheat–oat composite systems during baking, particularly with regard to matrix-dependent analytical responses, remains unclear. This study evaluated the compositional changes, technological performance, and sensory quality of wheat bread enriched with various forms of oat. Composite flours containing 5–15% wholegrain oat flour, commercial oat bran, milled commercial oat flakes, or milled sprouted oat grain (sprouted under laboratory conditions for three days at 25 °C) were prepared using the Slovakian oat cultivar ‘Peter’. The raw materials, flour blends, and baked breads were analysed for β-d-glucans (BG), total dietary fibre (TDF), starch, proteins, and lipids using standardised enzymatic, gravimetric, and polarimetric methods. Bread quality was assessed through loaf volume measurements and a sensory evaluation using a 5-point hedonic scale by seven trained panellists. Multivariate statistical analysis was applied to integrate compositional, technological, and sensory data. Compared to wheat flour (0.24% BG and 3.45% TDF), the incorporation of oats significantly increased the contents of BG, TDF, proteins, and lipids, with oat bran showing the strongest enrichment effect (owing to 15.69% TDF in the raw material). Baking induced oat-form-dependent changes in the measured BG and TDF content. The level of BG diminished in wholegrain oat blends but increased or remained stable in bran-rich systems. This reflects differences in matrix structure and analytical extractability, rather than true compositional gains. Meanwhile, starch content consistently declined across all composite breads. Fibre-rich formulations exhibited reduced loaf volume and altered both bread geometry and morphology, particularly at 15% substitution. Breads containing 5% oat flour or moderate levels of oat bran (5 or 10%) were considered the most acceptable in terms of nutritional enhancement and quality attributes. Germinated oat breads showed the greatest technological impairment and the lowest sensory scores. Overall, moderate oat enrichment strikes a balance between nutritional improvement and technological performance without significantly compromising sensory quality. These findings emphasise the significance of matrix effects when interpreting standard total dietary fibre and β-d-glucans analyses and offer an integrated analytical and technological framework for the rational design of fibre-enriched cereal products.

The study aimed to elucidate compositional changes in free phenolic compounds (fPHEs) during bakery processing of wheat flour supplemented with grape pomace (GP) and to assess dough rheology, bun shape and physical characteristics. Three GP variants were used—two from white cultivars (Rhine Riesling; Rhine Riesling + Muscat of Moravia) and one from a red blend (Saint Laurent and André)—at substitution levels of 5, 10, 20, and 30%. Thirty-four fPHEs were quantified by high-resolution UHPLC-MS-Orbitrap; dough rheology was assessed by Mixolab; and potential fPHE–wheat macromolecule interactions were examined via FTIR spectroscopy. Wheat flour contained only six fPHEs at low concentrations. Both white GP samples had similar profiles of 32 fPHEs, dominated by miquelianin (526–683 µg/g) and hyperoside + isoquercetin (390–476 µg/g). Red GP was highly enriched in anthocyanins (>30,000 µg/g) and generally exceeded white GP in most fPHEs. Even 5% GP substantially increased fPHE concentrations throughout processing. Several compounds (e.g., gallic acid, miquelianin) exceeded theoretical values, suggesting release from bound forms during fermentation and heating, whereas anthocyanins lost at least 30% during baking. Rheological analysis showed shorter dough development and reduced stability with increasing GP. White GP enhanced starch gelatinization (C3), gel stability (C4), and retrogradation, whereas 20% red GP markedly impaired gelatinization. GP additions ≥10% deteriorated bun shape and physical properties. FTIR confirmed spectral shifts likely due to fPHE–protein/starch interactions. In summary, incorporation of just 5% GP enhanced the nutritional profile of wheat buns.

This study investigated the chemical composition and sensory acceptability of yeasted steamed wheat dumplings – a typical Central European side dish – that were fortified with wholegrain oat flours derived from two distinct cultivars – hull-less Inovec and hulled Prokop. The flours were used at 7 substitution levels, ranging from 2.5 to 25.0%. Chemical analysis of both flour mixtures and steamed dumplings revealed a significant modulation of macronutrient profiles with increasing oat inclusion. As presumed, the β - d -glucans content increased proportionally with the addition of oats, reaching up to 1.23% in flour mixtures (Prokop) and 0.80% in steamed dumplings (Inovec). Furthermore, enrichment by oat resulted in higher protein (up to 15.05%), lipid (up to 12.13%), and dry matter contents, while reducing starch levels. Two-factorial ANOVA attributed the most variance in nutritional traits (e.g., 87% for β - d -glucans) to the level of wheat flour substitution, with minor effects coming from the oat variety. The correlation analysis confirmed strong formulation-dependent trends, particularly for β - d -glucans ( r = 0.972), lipids ( r = 0.919), and proteins ( r = 0.831), with the thermal stability of key nutrients demonstrated in all processing stages. Sensory evaluation revealed an inverse relationship between oat content and dumplings acceptability, primarily due to undesirable changes in color, aroma, and texture at higher inclusion levels. Multivariate PCA and two-way joining heatmap analysis highlighted that measurable nutritional enhancement was evident from the addition of just 2.5% oat flour, while the most favorable balance between an improved nutrient profile and retained sensory attributes was observed at inclusion levels of 10–15%. Oat Inovec-enriched samples exhibited superior protein and lipid content yet were more prone to sensory degradation at high inclusion rates. Overall, fortification with oat flours at levels of up to 10–15% is identified as an effective strategy for developing nutritionally enriched, fiber-rich yeasted steamed products with minimal sensory compromise. The findings emphasize the importance of balancing nutritional gains with sensory acceptability in the design of functional cereal-based foods.

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.

Cereal (1,3)(1,4)-β-d-glucans, known as β-d-glucans, are cell wall polysaccharides observed in selected plants of grasses, and oats and barley are their good natural sources. Thanks to their physicochemical properties β-d-glucans have therapeutic and nutritional potential and a specific place for their functional characteristics in diverse food formulations. They can function as thickeners, stabilizers, emulsifiers, and textural and gelation agents in beverages, bakery, meat, and extruded products. The objective of this review is to describe the primary procedures for the production of β-d-glucans from cereal grains, to define the processing factors influencing their properties, and to summarize their current use in the production of novel cereal-based foods. Additionally, the study delves into the utilization of β-d-glucans in the rapidly evolving field of nanotechnology, exploring potential applications within this technological realm.