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The effect of different degrees of deacetylation (DDs) of deacetylated konjac glucomannan (DKGM) on the gluten structure, water state, and yeast activity of frozen dough was evaluated. The moderate DKGM group maintained a more continuous gluten network after three freeze-thaw cycles, as evidenced by an 8.67% increase in disulfide bond content and a 15.01% increase in α-helix content compared to the KGM group. DKGM effectively impeded bound water migration, with the moderate DKGM group retaining 8.28% more bound water than the KGM group after three freeze-thaw cycles. The stabilization of gluten structure and water state in frozen dough by DKGM resulted in higher yeast activity in the low and moderate deacetylation groups (DD = 31.31% and 50.24%). Additionally, DKGM enhanced the quality of frozen steamed bread. The results indicate that DKGM with a moderate DD (50.24%) effectively alleviates the quality deterioration of frozen dough. These findings suggest that DKGM has great potential as a novel cryoprotectant for frozen dough, with DD being a crucial factor in its cryoprotective effect. [Display omitted] • Moderate DD (50.24%) of DKGM reduced quality loss in frozen dough. • Moderate DD of DKGM enhanced gluten structure in frozen dough. • DKGM inhibited water migration during freeze-thaw cycles. • DKGM with moderate DD improved yeast activity in frozen dough. • DKGM improved specific volume and texture of steamed bread from frozen dough. [ABSTRACT FROM AUTHOR]

Wheat flour substitution with flours from raw and roasted beans of Phaseolus coccineus at 20 and 30% (flour basis) was studied in breadmaking. The rheological behavior of starch-proteins networks in the composite flour doughs, composition and quality attributes of breads, bread staling events, in vitro starch digestibility of bread crumbs, and volatiles profile, were evaluated using a multi-instrumental analytical approach. According to oscillatory rheological tests, wheat flour substitution with bean flour enhanced the dough's firmness (G′, η*), implying a greater dough resistance to flow and deformation. Nevertheless, the specific volume of breads with roasted beans flour improved, compared to those fortified with raw bean flour, and was comparable to control wheat bread. The texture profile analysis of breads with raw bean flour indicated a greater degree of crumb hardening at the end of storage, despite the lower extent of amylopectin retrogradation, as determined calorimetrically (DSC). FTIR spectroscopy for breads containing bean flour showed little differentiations in the secondary protein structures between fresh and stored crumbs; generally, the β-type structures (β-sheet, aggregates and β-turn) prevailed in all samples at the expense of other secondary conformational elements in the crumb protein networks. The in vitro starch digestibility of fortified bread crumb showed reduced glucose release responses compared to wheat flour bread. The typical "beany" flavor notes of fortified breads were masked using the roasted bean flour; this was corroborated by a modified profile of bread volatiles, resulting in a pleasant sensory appeal for the 20%-substituted product and a more favourable consumer acceptability. [Display omitted] • Wheat bread was fortified (20, 30 %) with flours from raw and roasted Phaseolus coccineus seeds. • All fortifications with bean flours increased water absorption and dough firmness. • The fortified breads showed greater crumb hardening upon storage. • Minor changes in protein conformational elements were noted by FTIR spectroscopy. • Fortified breads with roasted bean flour showed masking of 'beany flavor' notes. [ABSTRACT FROM AUTHOR]

Wheat starch was modified through octenyl succinic anhydride (OSA) esterification combined with enzymatic hydrolysis using glucoamylase and α-amylase to produce four modified starches, namely, OSA-modified starch (OSAS), enzyme-modified starch (EMS), OSA-enzyme-modified starch (OEMS), and enzyme-OSA-modified starch (EOMS). The effects of modification methods on the physicochemical properties and internal structure of starches were investigated. The effects of starch modification contents (2%, 4%, and 6%) on the functional properties of wheat dough were also studied. The internal structure of the modified starches was analyzed through Fourier transform infrared spectroscopy and scanning electron microscopy. Results showed that starch molecules were successfully integrated in OSA, and glycosylase action was inhibited. Differences in the physicochemical properties of the modified starches were analyzed from the perspective of intermolecular hydrogen bonds and other molecular forces. The dough added with 6% OEMS showed significantly reduced water fluidity and improved viscoelasticity. This work provides a new way to optimize the storage stability and processing performance of dough. [Display omitted] • Esterification first occurs on the surfaces of starch molecules. • OSA can inhibit glucoamylase action. • Starch formed porous structures after enzymatic hydrolysis, and part of OSA entered starch molecules. • Enzymatic hydrolysis could effectively improve the functionality of esterified starch. • Starch esterified via enzymatic hydrolysis can improve dough viscoelasticity and stability and reduce water flow. [ABSTRACT FROM AUTHOR]

This study investigates the impact of various salts (NaCl, KCl, CaCl₂, MgCl₂) on gluten aggregation, with an emphasis on the role of high-molecular-weight glutenin subunits (HMW-GS) in modulating these impacts. The results demonstrated that NaCl significantly improved dough springiness and adhesiveness, while divalent salts like CaCl₂ and MgCl₂ had a greater effect on increasing dough hardness, with KCl showing the least impact among all salts. Differential responses were observed in HMW-GS deletion lines, where Bx7 was more responsive to NaCl and CaCl₂, whereas By8 showed stronger interactions with KCl and CaCl₂. The observed reductions in zeta potential and decrements in ionic bond content during salt-induced gluten aggregation supported the 'electrostatic shielding' mechanism, with hydrophobic interactions and hydrogen bonding emerging as key contributors to aggregate stability. Molecular dynamics simulations further corroborated these findings, revealing stronger Coulomb-SR interactions and enhanced binding affinities for divalent ions, in agreement with experimental data. These insights provide a theoretical foundation for optimizing low-sodium formulations in wheat-based products. [Display omitted] • Bx7 and By8 deletion exhibited distinct responses to varying salt environments. • Bx7 deletion reduced gluten aggregation under NaCl and CaCl₂ treatments. • By8 deletion reduced gluten aggregation under KCl treatment. • Molecular dynamics unravel ion-specific mechanisms driving gluten network stability. [ABSTRACT FROM AUTHOR]

This study explored how high-molecular-weight glutenin subunits (HMW-GS) at the Glu-B1 locus impact gluten deterioration during dough frozen storage and freeze-thaw (F/T) cycles. Using deletion lines, we found that the deletion of specific HMW-GS, particularly Bx7 , led to a greater reduction in glutenin macropolymer (GMP) wet weight during storage, especially under F/T cycles. The frozen conditions triggered more dissociation of hydrogen and disulfide bonds, generating more protein monomers and resulting in severe gluten deterioration in the Bx7 deletion. Additionally, protein structures in these lines were more vulnerable to damage during F/T cycles due to temperature fluctuations. In silico analysis further confirmed that Bx7 had better stability and antifreeze activity compared to By8 , explaining why its deletion had a more pronounced effect on gluten stability. These findings offer significant implications for the food industry, particularly in enhancing the quality, shelf-life, and commercial viability of frozen dough products by providing a deeper understanding of the mechanisms behind gluten deterioration, specifically the role of high-molecular-weight glutenin subunits. [Display omitted] • HMW-GS deletion had a promotive effect on gluten deterioration during dough frozen treatment. • The freeze-thaw cycle accelerated deterioration process in HMW-GS deletion lines. • The conformational structure in HMW-GS deletion lines were sensitive to dough frozen treatment. • Bx7 exhibited higher structural stability at low-temperature compared to By8. [ABSTRACT FROM AUTHOR]

The suitability of microwave-assisted hydrothermally treated (MWT) quinoa flour was investigated as an ingredient for enhancing the quality of gluten-free (GF) bread fortified with quinoa. Different levels (0%, 25%, 37.5%, 50%, and 75%) of native/untreated (N) or MWT quinoa flour (30% moisture content, 9 W/g, total 8 min of microwave exposure) were evaluated to replace maize starch in a starch-based GF recipe. The hydration of the dough was adjusted to obtain similar consistency in terms of complex modulus, G 1 *, to compensate its increase due to quinoa addition and treatment (up to +737%). The incorporation of increasing amounts of native quinoa flour reduced dough viscosimetric profiles, delayed its gelatinization peak in DSC scans (up to +3.4 °C), and decreased the dough's development and stability during the fermentation test (the final height decreased from 88 mm for 0% quinoa to 4 mm for 75%). When substituting native by MWT quinoa flour at a certain substitution level, a reduction in the breakdown viscosity, an increase in pasting temperature, and an increase in dough development and stability during the fermentation test were noted. As a result, the MWT quinoa flour-fortified breads exhibited a higher specific volume, lower hardness, and retarded staling. In addition, sensory evaluation of the breads showed a reduction in the herbaceous off-flavour associated with the quinoa (untreated) flour, and no effect on bitterness. The experimental findings indicate the feasibility of using microwave hydrothermal treatment to improve the physical properties and sensory quality of quinoa-enriched GF bread. [Display omitted] • Microwaved-quinoa flour enhanced gas retention capacity of gluten-free (GF) dough. • Addition of microwaved-quinoa flour improved dough development. • Microwave treatment (MWT) enhanced the volume of quinoa-enriched GF bread. • MWT reduced quinoa herbaceous associated off-flavour. • MWT improved physical and sensory qualities of quinoa-enriched GF bread. [ABSTRACT FROM AUTHOR]

Bread staling is a complex phenomenon in which multiple interconnected mechanisms involving water operate, including the formation of amylopectin crystallites sequestering water, crumb-to-crust moisture migration, and the escalating immobilization of water reducing gluten plasticization. Considering the pivotal role of water-gluten-starch interactions, the integration of the highly-soluble, water-avid, arabinoxylan-rich psyllium husk (PSY) into a wheat dough/bread system was explored, to understand the impact of PSY on the water and biopolymer dynamics that could lead to lower staling. With the addition of PSY, optimal dough development required more water (from 68.0 to 119.5 % in control and 10 % wheat flour replacement with PSY, respectively). LF-NMR showed a parallel increase in the proton population attributed to free water entrapped by the continuous network of biopolymers surrounding granular starch (A 23), and its relaxation time (T 23). PSY resulted in freshly baked bread with similar specific volume, porosity and starch gelatinization than the control, but with a much higher proportion of intergranular free water (A 23). Importantly, PSY did not affect amylopectin retrogradation nor shortened the relaxation time of water protons in exchange with gluten, suggesting that PSY did not withdraw plasticizing water from starch or gluten, respectively. During storage, PSY resulted in a dose-dependent delay of both crumb hardening (correlated to T 23 , r = −0.76, p < 0.05) and loss of cohesiveness (correlated to T 23 , r = 0.71, p < 0.05 and A 23 , r = 0.74, p < 0.05). PSY also resulted in greater crumb resilience, which was related to the self-assembly of PSY molecules and its impact on dough elasticity (with up to two-fold increase in recovery strain). [Display omitted] • With the addition of psyllium husk (PSY), dough development required more water. • PSY enabled greater dough and bread hydration in the form of intergranular water. • PSY did not withdraw plasticizing water from starch or gluten during storage. • The antistaling effect of PSY was related to intergranular water and gluten plasticization. • PSY doubled dough elasticity and enhanced the resilience of fresh and stored bread. [ABSTRACT FROM AUTHOR]

Experimental and numerical modelling work related to microstructure and deformation of starch, gluten and wheat dough was presented. Atomic force microscopy analyses through force spectroscopy on starch samples showed elastic behaviour of both dried and reconstituted wet starch granules, where wet starch was shown to be more cohesive than dried starch. Deformation-recovery test over time under compression mode showed almost complete recovery to original sample height of gluten, whereas only a slight recovery was observed for dough. Finite element modelling was then commenced to simulate gluten deformation-recovery and starch-gluten dough deformation. The gluten geometry used for the starch-gluten dough model was obtained from cryo-SEM image from the previous work before the starch geometry was then included. The interface between the starch and gluten model was defined using viscoelastic cohesive zone elements. The modelling results suggested significant influence of gluten cellular structure towards starch-gluten dough integrity. In addition, the results from the current work further supported the previous report of the starch-gluten interfacial behaviour using viscoelastic cohesive zone model. [Display omitted] • Complete recovery gluten compared to dough from compression recovery test. • Force spectroscopy showed high adhesiveness of wet starch compared to dry starch. • Significant influence of cellular structure of gluten towards starch-gluten dough integrity from modelling results. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the relationships among glass transition features, macroscopic, mesoscopic properties of dough regulated by linear dextran (backbones of α-(1 → 6) linkages) varying with weight-average molecular weights (M w : 5 kDa, 40 kDa, 200 kDa). The glass transition temperatures (T gm1 ' and T gm2 ') of dough were obviously increased with increasing dextran M w at due to the lowered mobility of water and other biopolymer molecules. The sound hydrophilicity and steric hindrance of higher M w dextran caused the increment of non-freezing water content (NFW) and the reduction of ice melting enthalpy. Significant increase in the β -sheet content of gluten protein and the average pore size and fraction dimension of dough microstructure were observed by increasing dextran M w , indicating the improvement of uniformity and stability of dough structure. Dough rheology and texture clarified that the higher M w dextran increased the elastic moduli and decreased the maximum creep strain value, strengthening the elastic behavior and hardness of dough especially at the lower addition amount (≤1%). Positive correlation of T gm1 ', T gm2 ' with NFW、 β -sheet content and extension area was revealed for the first time. These results provided a new insight to improve the quality and stability of dough by regulating the glass transition features with different M w dextran. [Display omitted] • T gm1 ' and T gm2 ' of dough increased with rising dextran M w due to the limited molecular mobility. • Higher M w dextran caused the increment of NFW and reduction of ice melting enthalpy. • Improved uniformity and stability of dough structure were observed with higher M w dextran. • Elasticity and hardness of dough were enhanced with higher M w dextran at added amounts ≤1 %. • Positive correlation of T gm1 ', T gm2 ' with NFW、 β -sheet content and extension area was revealed. [ABSTRACT FROM AUTHOR]

This work explores the potential of short-chain fructooligosaccharides (sc-FOS) as a sugar replacer in bakery products, particularly croissants. The effects of sucrose replacement with sc-FOS on croissant dough properties, as well as the quality of baked croissants, are studied. It was found that the changes in croissant on inclusion of sc-FOS are primarily related to changes in water redistribution and the binding state of water in the dough, with minimal role of change in secondary structure of proteins. Rheological properties of sugar-reduced croissant dough were characterized. The use of sc-FOS as a sucrose replacement increased storage and loss moduli, indicating enhanced interactions and a firmer dough. Creep compliance revealed less deformation and improved elastic recovery, suggesting strengthened bonding, especially in the gluten network. The upper crust of croissants showed no significant differences in colour, but the lower crust darkened slightly with sc-FOS. Texture analysis revealed a firmer texture with complete sucrose replacement, while the porosity remained consistent. Sensory evaluation indicated changes in hardness and overall acceptability with sc-FOS, emphasizing the need for reformulation and consideration of the impacts on starch gelatinization. [Display omitted] • Sc-FOS used to lower sugar and increase fiber in croissants. • Sc-FOS alters water state and protein structure (FTIR). • Sc-FOS acts as a dough strengthener: increased moduli and improves elasticity. • Sc-FOS results in altered hardness and acceptability. • Study's contribution: insights on sugar reduction in bakery. [ABSTRACT FROM AUTHOR]

Starch granule-surface proteins (SGSPs) and gluten proteins can interact to influence dough quality. Despite their pronounced effects, the interaction mechanism remains insufficiently understood. Herein, the binding mechanism between SGSPs and different molecular weight glutenin was explored by experimental methods and single-molecule techniques. Our findings revealed that SGSPs promoted strong binding with both high and low molecular weight glutenin (HMW-GS and LMW-GS). When the ratio of SGSPs and LMW-GS increased to 2:1, the content of disulfide bond increased from 0.03 μmol/L to 0.21 μmol/L while the free sulfhydryl showed the opposite pattern, indicating a tightly packed composite protein structure. A combination of unbiased and steered molecular dynamics simulations further revealed that SGSPs exhibited a higher binding affinity towards LMW-GS in comparison to HMW-GS due to the contributions of solvation and specific interaction energies. This endows the SGSPs-LMW-GS complex with significantly enhanced stability at free state and much higher unbinding force upon stretching, substantially improving the mechanical quality of dough. These findings indicate that SGSPs predominantly affects the interactions between starch and gluten, which will shed light on the dough formation and its properties. [Display omitted] • SGSPs bond with glutenin by hydrogen and disulfide bonding. • SGSPs bond more tightly to LMW than to HMW. • SGSPs-LMW complex had higher dissociation force than -HMW complex. • SGSPs-LMW complex enhanced stability and much higher unbinding force. [ABSTRACT FROM AUTHOR]

Hydrocolloids such as hydroxypropyl methylcellulose (HPMC) are commonly used in gluten-free (GF) products to mimic the viscoelastic properties of gluten. However, GF products must meet current consumer expectations by not only being tasty and nutritious, but also adhering to 'clean label' principles, which involve minimizing ingredients and additives and favoring natural over chemical components. Modifying GF flours via hydrothermal treatments offers an alternative approach to reduce the use of additives in GF products. This work applied response surface methodology to study the potential reduction in HPMC dose in the formulation of GF-breads by the addition of microwave-treated rice flour (MWF) (treatment conditions: 8 min, 9 W/g, 30% moisture), without impairing their appearance, volume, and texture. The optimization study also included Water level and HPMC dose, and evaluated the dough's rheological properties at constant hydration. GF breads were made by varying the amount of native flour substituted with MWF, water level, and HPMC dose. Replacing 50% or 80% of native rice flour by MWF allowed to reduce the usual HPMC dose by more than half. This resulted in higher loaf volume and a softer crumb than their counterparts made with untreated flour and baked with the usual dose of additive (2%). Doses of HPMC as low as 0.7% with 80% MWF still resulted in breads with good texture and acceptable volume. Therefore, the structuring effect of MWF and its good performance in GF baking have been concluded, allowing to reduce the dose of additives required in formulating GF bread. [Display omitted] • Microwave-treated flour (MWF) halves the need the HPMC in gluten-free breads. • 80% MWF, 1% HPMC and 80% Water produced breads with desirable volume and texture. • The incorporation of MWF modified dough consistency, increasing viscoelastic moduli. • Recovery capacity of the doughs was improved using MWF in the formulation. [ABSTRACT FROM AUTHOR]

Our study investigated the impacts of starch botanical origin (tapioca versus wheat starch) and gluten addition on the water distribution and hydrothermal changes of starch in model dough systems compared to their pure starch counterparts. In it, we employed a combination of time-domain nuclear magnetic resonance (TD-NMR), wide angle X-ray diffraction (WAXD), solid state nuclear magnetic resonance (ssNMR) at variable temperature (VT) and differential scanning calorimetry (DSC) measurements. The results showed that at intermediate hydration levels, water ingress into starch granules, increase in glucan chain mobility, and dissociation of double helices (DH) of amylopectin occurred at lower temperatures than crystallite loss of order and melting. The inhibitory effect of gluten on wheat starch hydrothermal changes was explained by a higher water adsorption capacity of gluten compared to starch at this hydration level (50%, wb). However this effect was shown to be influenced by starch botanical origin, tapioca-based systems showing no hindrance effect of gluten on starch-water interaction. The study also provides additional evidence for the sensitivity and detection scales of the different techniques at 50% water content. [Display omitted] • Combined VT TD-NMR, WAXD, ssNMR, DSC for effective analysis of dough hydrothermal changes. • Multi-scale investigation of heat-induced transformation of starch and gluten in model dough systems. • Multi-scale study to probe the inhibitory effect of gluten on starch hydrothermal changes in model dough systems. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the impact of carboxymethyl chitosan (CMCh) on rice dough quality during freeze–thaw cycles (FTCs). We conducted a comprehensive analysis of frozen rice dough using various techniques, including scanning electron microscopy (SEM), low–field nuclear magnetic resonance (LF–NMR), confocal laser scanning microscopy (CLSM), Fourier transform infrared spectroscopy (FT–IR), size–exclusion high–performance liquid chromatography (SE–HPLC), small–angle X–ray scattering (SAXS), X–ray diffraction (X–RD), differential scanning calorimetry (DSC), and rapid visco–analysis (RVA). Our results revealed that adding carboxymethyl chitosan (CMCh) to frozen rice dough reduced damage to starch granules and gluten proteins during FTCs compared to dough without CMCh. This resulted in the deceleration of the modification of the ordered protein structure. Furthermore, the inclusion of CMCh resulted in increased cross–linking with the large protein polymer, impairing the capacity of bound water to transition into free water within the frozen rice dough. Consequently, this led to an elevation in the storage modulus (G′), effectively retarding the textural transformation of the frozen rice dough. Introducing CMCh to frozen rice dough subsequently decelerated the alterations in the short-range order and crystal structures of starch, consequently modifying the pasting and thermal properties of the frozen rice dough. Based on the results obtained from our experiments, CMCh has a decelerating effect on the impact of frozen rice dough on FTCs. [Display omitted] • A new approach to improve on the quality of frozen rice dough was constructed. • Ice crystals destroyed the integrity of gluten and starch during freeze thaw cycles. • Carboxymethyl chitosan inhibited water migration of dough during freeze thaw cycles. • Carboxymethyl chitosan improved the rheological of dough during freeze thaw cycles. • Carboxymethyl chitosan interacted with gluten to prevent depolymerization. [ABSTRACT FROM AUTHOR]

Empirical rheological techniques conventionally used for evaluating wheat flour dough can be coupled to fundamental rheology, especially when viscoelastic properties of dough, like those with high bran content, cannot be readily investigated using empirical rheology alone. In this study, the correlations between the two types of rheology were evaluated considering flours with different extraction rate, from refined to whole grain ones. From empirical tests it resulted that flours with higher protein and fibre contents required more water to be optimally hydrated, showing also longer dough developing time. Higher tenacity and lower extensibility were also observed. Fundamental rheology assessed the viscoelastic character of the dough with a predominantly solid-like behavior, and a direct correlation between flour extraction rate and dough consistency was found. Dough made from less refined flours was less deformable and showed a more elastic recovery ability. Starch gelatinization temperature and process rate, increased and decreased, respectively, with the extraction rate. The existing correlations between empirical and fundamental rheology were used to estimate the alveograph parameters of blends of type 00 soft wheat flour enriched with 15% and 20% ground soft wheat bran. Overall, the study has shown that the combination of the two rheological approaches is useful to determine the best use of high-fibre flours that could not be determined by the official empirical methods. [Display omitted] • Empirical and fundamental rheology can be coupled for wheat dough characterization. • Empirical and fundamental rheology are highly correlated. • Rheological combined approach was effective also for bran-enriched dough characterization. [ABSTRACT FROM AUTHOR]

It is highly desirable to produce bread with both acceptable texture and health benefits. Glucosyltransferase B (GtfB), an enzyme with activities of 4,6-α-glucanotransferase, could increase the number of short branches and percentage of (α1→6) linkages in starch, resulting in slow digestibility and low retrogradation properties of starch. In this study, Streptococcus thermophilus GtfB enzymes were applied in the preparation of wheat flour dough and bread. With the addition of GtfB at 0.04–0.16 U/g flour, the smaller storage modulus (G′) and loss modulus (G″) of doughs over a frequency sweep range of 0.01–20 Hz were observed, and the specific volumes and the slowly digestible starch (SDS) contents of breads were increased by 2.3–11.4% and 19.7–35.0% (P < 0.05), respectively. GtfB-modified breads were softer and less gummy and chewy (P < 0.05) after storage at 4 °C for 7 days. Thus, these results suggest that S. thermophilus GtfB could be applied to improve the textural and digestive properties of bread. Image 10629171 • GtfB reduced viscoelasticity of wheat flour dough and retrogradation of bread starch. • GtfB-modified breads had bigger specific volume and more slowly digestible starch. • GtfB-modified breads were softer and less gummy and chewy after 7 days at 4 °C. [ABSTRACT FROM AUTHOR]

Reducing the sodium content of bread to meet desirable population health outcomes can lead to challenges dough processing, poor dough handling and rheology, and high stickiness. Our objective was to better understand the relationship of water and the dough components in low sodium dough environments. The water mobility, association, and diffusion characteristics of simple model doughs containing reduced NaCl (1% by flour wt.), organic acids (acetic, fumaric, or succinic at 1.2 mmol/100 g flour or a no acid control), and a dough improver (0.001% by flour weight glucose oxidase) using two cultivars (Pembina and Harvest) were assessed by 1H NMR. It was determined that the inclusion of the acids did not significantly affect the overall structure of the dough; the polymer backbones (protein and starch) were not significantly affected, however, the inclusion of acids or use of a stronger cultivar (Pembina) reduced molecular motion on the MHz timescale as assessed by T 1 and T 2. Motion on the kHz timescale was also altered. Samples which contained acid or were made from Pembina flour had less mobile water than those without acids, or doughs prepared with Harvest flour. The diffusion characteristics of water in the doughs were not altered by the acid or cultivar; however, diffusion was determined to be confined/restricted by the polymer matrix. Overall, the inclusion of acids alters molecular motion and interactions with the side chains of the polymer backbone, and further stickiness and handling investigations should focus on these areas to expand upon the relationship of water and stickiness/dough handling, which is a concern in low sodium doughs. Image 1 • Acid inclusion and flour type slow motion on MHz timescales (water tumbling). • Acid inclusion and flour type alter motion on kHz timescale (side chain motion). • kHz timescale motion changes need to be further characterised. • Diffusion behaviour was not affected by formulation changes. • No changes to polymer backbone suggesting motion altered at protein surfaces. [ABSTRACT FROM AUTHOR]

Effect of pigskin-originated gelatin on dough properties and bread characteristics, especially on bread staling was investigated in terms of starch retrogradation and water migration in the present study. Results showed that gelatin significantly improved bread qualities during storage. Compared with the control, 7-day staling rate of bread containing 0.5% and 1.0% gelatin decreased by 6.56% and 20.83% respectively, indicating gelatin retarded the staling process of bread. This retardation effect was related to starch retrogradation and water migration. The relative crystallinity decreased from 15.12%, 11.60% to 10.75%, which demonstrated the alleviation effect of amylopectin crystallization. Bread samples containing 1.0% gelatin had the lowest retrogradation enthalpy of 2.93 ± 0.24 J/g followed by 0.5% gelatin bread and the control group, further indicating that gelatin may induce less water available to form crystal lattice and restrict the migration of starch molecules. The 5-day moisture loss rate for the control group was highest with the values of 12.39%, which was 1.43% and 1.83% higher than that of bread with 0.5% gelatin and 1.0% gelatin, respectively. Water activity and T 2 relaxation results provided the information that gelatin inhibited water migration upon storage and gelatin interacted with bread components. However, the effect of gelatin on improving bread quality and retarding staling could not be reflected by the dough properties measured through farinograph, extensograph and rheometer. This study suggested gelatin from pigskin had great potential to be served as an effective bread improver. Image 1 • Gelatin enhanced the bread qualities significantly, especially retarding the staling process. • Gelatin hindered the chain reassociation of starch molecules during storage. • Gelatin interacted with bread components and restricted water transfer. • Dough properties showed gelatin might to some extent weaken the gluten network. [ABSTRACT FROM AUTHOR]

The objective of this work was to investigate the possibility of a macromolecular network formation in gluten-free model dough systems based on millet flours (white and wholemeal) by the addition of rye bran arabinoxylan (AX) and enzyme treatment. To perform enzyme treatment pyranose-2-oxidase was applied, which was assumed to be able to initiate cross-links between AX molecules through H 2 O 2 production. The effect of AX addition and enzyme treatment on the rheological properties of the model systems was studied by basic (oscillation measurement) and applied (micro-doughLab, Rapid Visco Analyzer and Mixolab) rheological methods. The molecular basis of AX crosslinking was investigated in lyophilized dough and/or gel samples by SE-HPLC and Scanning Electron Microscopy (SEM). The results showed that AX addition deteriorated the mixing and pasting properties in general, but these properties were significantly improved when it was combined with enzyme treatment. In some cases, enzyme addition itself also changed the behaviour of the model systems significantly, suggesting that the enzyme may have an effect on other flour components (e.g. proteins, starch), as well. The study of AX molecular weight distribution performed by SE-HPLC confirmed the appearance of a new peak in the higher molecular weight range when enzyme treatment was applied to AX dosed dough systems, supporting our initial assumptions. According to SEM images of dough and gel microstructures, significant association was observed between starch granules when AX and enzyme treatment were applied together indicating a possible formation of a macromolecular network. Image 1 • Initiation of macromolecular network formation in gluten-free model systems. • Arabinoxlyan (AX) addition alone could not improve the technological properties. • AX addition with enzyme treatment resulted changes in molecular structure and rheological behavior. [ABSTRACT FROM AUTHOR]

Abstract The physical modification of rice flour by heat-moisture treatment assisted by microwave radiation and its effect on the rheological and pasting properties of gluten-free doughs and the physical quality of their resulting bread was investigated. Two levels of flour initial moisture content, 20% (MW-20%) and 30% (MW-30%) and two levels of its addition (30% and 50%) to the dough were evaluated to assess the potential of the physical treatment to modify dough viscoelasticity and bread-making ability. MW-30% treated rice flour showed the most notable results. It provided enhanced dough viscoelasticity vs the control (100% native rice flour), increasing the dough G 1 ′ modulus up to 69% and 135% for the treated flour additions of 30% and 50% of MW-30% respectively. The treated flour increased the resistance of doughs to deformation and enhanced their elastic behavior and recovery capacity up to 170% when compared to the control dough. The major effects on pasting parameters were also obtained for the doughs formulated with MW-30% flour at the maximum substitution level (50%). It delayed the pasting temperature, decreased the peak, trough and final viscosities with respect to the control dough. Both MW-treated rice flours (MW-20% and MW-30%) led to bread with higher-specific volume, softer crumb and delayed staling. The MW assisted heat moisture treatment of rice flour seems to be a valuable procedure to improve the viscoelastic behavior and bread-making performance of gluten-free doughs. Graphical abstract Image 1 Highlights • Microwave treatment of rice flour affects the viscoelasticity of gluten-free doughs. • Microwave irradiation of flour increases the dough pasting temperature. • Viscometric profiles are significantly lower in doughs made with treated flours. • Breads made with treated-rice flour had a higher volume and lower firmness. • The moisture content of flour plays a key role in the effect of microwave treatment. [ABSTRACT FROM AUTHOR]

Abstract Wheat dough is subjected to large deformations under realistic processing conditions. The viscoelasticity under large deformations can be hardly captured by traditional small amplitude oscillatory tests. Large amplitude oscillatory shear (LAOS) tests are required for accurate characterization of the nonlinear mechanical response. In this regard, LAOS studies of yeasted wheat dough leavened at different times (0, 30, 60, 90 and 120 min) were carried out in this work, in the strain range from 0.1% to 100% (frequency 2π rad/s). All the dough samples showed a complex rheological response that was characterized by strain stiffening and shear thinning behavior at large strains. FTIR analysis revealed that starch granules were increasingly hydrated and protein molecular configuration was modified by the yeast activity. It was postulated that modifications of the protein secondary structure can be behind the strain stiffening behavior while the suspended starch matrix was associated with the shear thinning behavior. LAOS enabled to disaggregate the viscoelasticity of the wheat dough to assess the nonlinear effects associated with elasticity and energy dissipation mechanisms. Overall, a longer leavening time increased by about 30% the nonlinear mechanical response of wheat dough, an effect probably induced by variations in the secondary structure of wheat proteins and to the gassing of the dough microstructure as consequence of the yeast metabolic activity. The results in this work showed that LAOS is a suitable method for characterization of the nonlinear mechanical response of whet dough, especially for assessing the effect of processing conditions (e.g., leavening time and yeast content). Graphical abstract Image 1 Highlights • Large amplitude oscillatory properties of wheat flour dough were studied as function of leavening time and yeast content. • Nonlinear viscoelastic response quantified by harmonic distortion increased by 30% after leavening for 120 min. • Strain hardening and shear thinning behaviors increased with leavening time and were sensitive to the yeast content. • Hydration and protein secondary structure are the main mechanisms involved in nonlinear viscoelastic response. [ABSTRACT FROM AUTHOR]

The effects of adding pea protein isolate (PPI) as a co-protein to calcium hydroxide deamidated zein were evaluated by fundamental rheological properties of gluten-free doughs measured at room temperature and FT-IR. Rice starch was used as a carbohydrate source at a constant concentration. Gluten-free doughs prepared with PPI, PPI + zein, zein under alkaline conditions, and PPI + zein under alkaline conditions were compared with a control sample containing gluten. Small and large deformation rheological tests indicated that the combination of PPI and the alkaline treatment of zein improved the gluten-free rheological properties, leading to a similar rheological performance to the control containing gluten. The sole addition of PPI to zein, or the alkaline deamidation of zein alone, did not generate doughs with desirable rheological behaviors. Quantification of the different conformations of the protein's secondary structure by FT-IR analysis confirmed that better rheological properties of dough containing PPI and zein under alkaline conditions are associated with higher amounts of β -sheets conformations. The use of zein is often limited to temperatures above its glass transition temperature (≈28 °C), but the results from this study provide important insights for the application of zein at room temperature in gluten-free doughs. [Display omitted] • Zein deamidation enhanced viscoelasticity of gluten-free doughs at room temperature. • Adding pea protein to deamidated zein produced doughs with gluten-like behavior. • Rheological behavior of gluten-free doughs was associated with β -sheet contents. • Sole PPI addition or zein modification were not enough to get desired properties. [ABSTRACT FROM AUTHOR]

The unfermentable nature of cellulose limits its physiological benefits as a dietary fibre. Recently, we drastically increased the fermentability of microcrystalline cellulose by human colon microbiota by reducing its crystallinity and polymer chain length (Thielemans et al., 2023). Here, the techno-functional impact of incorporating amorphised cellulose, depolymerised cellulose and amorphised depolymerised cellulose on bread making is investigated. Microcrystalline cellulose and its modified counterparts could be incorporated into bread at a 5 w/w% substitution level without significant volume losses. At a 20 w/w% substitution level, microcrystalline cellulose incorporation caused a loss of 36.4 ± 2.9% in bread loaf volume, while depolymerised celluloses reduced bread volume much less (16.2 ± 1.9%). In-depth characterisation of cellulose samples and 1H NMR and rheological measurements on bread dough revealed that the modified celluloses affected the water balance and gluten hydration in dough less than microcrystalline cellulose. These results complement insights on the importance of water-insoluble dietary fibre structure and hydration behaviour on bread (dough) quality. [Display omitted] • Milling and acid hydrolysis impact the hydration properties of cellulose • Cellulose hydration properties impact the quality of cellulose-enriched bread dough • Cellulose displaying low water retention is promising for fibre-enriched bread [ABSTRACT FROM AUTHOR]

Wheat flour doughs were prepared from four commercial wheat flours at different mixing times and hydration levels in order to obtain variations in their rheological properties and gluten network structure. Their rheological behavior was assessed by Dynamic Mechanical Analysis (DMA) for their viscoelastic properties and by Lubricated Squeezing Flow (LSF) for their extensional properties. Gluten network structure was determined by quantitative analysis of confocal microscopy (CLSM) images. Among the rheological properties, the consistency index (k) derived from the extensional viscosity and the elastic modulus ratio (E′ Max /E′ Min) varied between 10 and 42 kPa.sn, and 4 and 26, respectively. They were found to be consistently linked to the gluten network structure. This structure was primarily described by the morphological descriptor, "protein width", which defines the thickness of protein strands, the average value of which varied between 1.7 and 2.5 μm. Both rheological properties and morphological criteria were significantly influenced by dough hydration rather than by mixing time, whereas the flour characteristics did not play a major role. Interpretation of these results, supported by previous 1H time domain nuclear magnetic resonance (TD-NMR) results concerning water distribution profiles, showed that an optimal dough is defined by a high dough consistency index (k) and a highly cross-linked gluten network (low E' Max /E' Min ratio), presenting thin protein strands. The variations of the normalized (extensional) consistency (k*) with normalized modulus ratio (E′ Max /E′ Min *) of wheat flour doughs, prepared under various mixing and hydration conditions, can be ascertained by the morphology of the gluten network, described after quantitative analysis of images from confocal scanning laser microscopy (CSLM). [Display omitted] • Dough extensional properties at low and large deformations were in agreement. • Gluten network structure was assessed by quantitative image analysis. • Protein strand width is main morphological descriptor influencing dough consistency. • Gluten network structure was primarily determined by water distribution in the dough. [ABSTRACT FROM AUTHOR]

Flours from lentil seeds, raw or sprouted (either lyophilized or roasted before grinding), were used for wheat flour substitution in breads. The physicochemical properties of the obtained flours and doughs as well as bread quality attributes and staling were examined. FTIR spectroscopy revealed that sprouting altered the secondary structure of the lentil protein matrix by decreasing β-turns and random coils, and increasing β-sheets, α-helices and aggregates, while roasting subsequently eliminated these changes. Calorimetry (DSC) showed that the roasted-sprouted lentil flour was partially gelatinized. Oscillatory and creep-recovery rheological tests showed that doughs fortified with roasted-sprouted lentil flour at 15 and 20% (flour basis) substitution level were more viscous and elastic. Breads made with 10% lyophilized-sprouted lentil flour exhibited the lowest specific volume, and the highest crumb hardening and starch retrogradation rates as well as the greatest increase in protein β-sheets in the composite protein-starch matrix. Instead, the formulation with 10% roasted-sprouted lentil flour did not show major changes in loaf specific volume and extent of starch retrogradation, following 4 days of storage, while exhibited significantly improved crumb textural characteristics compared to bread made with wheat flour alone, receiving the highest overall acceptability scores among all fortified products tested due to its pleasant roasted-like flavor note detected by sensory assessors. These findings suggest that a successive process of sprouting and roasting of lentil seeds could be an innovative approach to fortify wheat flour-based breads for improving their nutritional quality while maintaining desirable textural and sensorial attributes of the baked product. [Display omitted] • Roasted-sprouted lentil flour (10–20%) increased wheat dough viscosity and elasticity. • Lyophilized-spouted lentil flour (10%) downgraded wheat bread quality attributes. • Roasted-sprouted lentil flour (10%) improved the textural characteristics of wheat bread. • Roasted-sprouted lentil flour (10%) extended the shelf life of wheat bread. • Roasted-sprouted lentil flour (10%) attenuated the off-flavors in the fortified breads. [ABSTRACT FROM AUTHOR]

3D printing can be used to develop texture-modified foodstuffs that are nutritious and appealing to meet the demands of special consumer needs such as those of the elderly with swallowing disorders (dysphagia). In this work, vegetable-containing protein-based food with different internal 3D structures (infill rates of 12.5, 25, and 50%) was elaborated using 3D printing. First, doughs with different soy protein isolate (SPI) content (20, 25 and 30 w/v %) were prepared to select the dough with the most suitable shape fidelity after being printed in an extrusion 3D printer, the dough with 25% SPI (25-SPI) in this case. Then the 25-SPI doughs with 10, 20 and 30 wt % red cabbage (RC) were prepared, and rheologically and physicochemically analysed before printing. All doughs presented a shear thinning behaviour since the viscosity decreased when the shear rate increased, a suitable rheological behaviour for 3D printing. Regarding the effect of RC in the food formulation, viscosity and storage (G′) and loss (G") moduli increased as RC content increased, with G' > G" for all doughs, indicating a solid-like behaviour, beneficial to maintain the shape and size of the food sample once it has been printed. 3D printed samples were homogeneous and showed cavities which got reduced gradually as more RC was added to the doughs, as confirmed by SEM analysis. Besides, the texture profile analysis showed that the hardness, gumminess and chewiness of the hydrated samples increased when the infill of the samples increased, while the addition of RC had an opposite minor effect. All food samples were labelled as transitional food, as defined by the International Dysphagia Diet Standardization Initiative (IDDSI) framework. [Display omitted] • Red cabbage (RC)-containing soy protein isolate (SPI) doughs were prepared. • All the doughs presented shear-thinning and solid-like rheological properties. • Food samples with different infill rates were successfully 3D printed. • Hardness, gumminess and chewiness increased as the infill rates increased. • All printed samples were categorized as transitional food as defined by the IDDSI. [ABSTRACT FROM AUTHOR]

Abstract Barley rusks are traditional baked products of the Cretan-Mediterranean diet, a naturally β-glucan-containing food item. The impact of flour particle size and autoclaving on dough thermomechanical properties and rusk quality features was evaluated. Rusks were made using a coarse and a fine barley flour stream without or with prior autoclaving at two different moisture levels. Calorimetry showed that autoclaving and decreased particle size of the flour reduce the gelatinization enthalpy values. Small and large deformation mechanical tests revealed that flour autoclaving increased the resistance to deformation and flow, elasticity and hardness of the barley doughs; these trends were more pronounced for coarse flours. The reduction of particle size in thermally untreated flours decreased rusk hardness and increased loaf volume and resulted in finer crumb structure; however, autoclaving of fine flour nullified these quality attribute trends. Nevertheless, these changes are not detrimental for consumer acceptability of this bakery product which traditionally is manufactured with low loaf volume, compact macrostructure and hard texture. Moreover, the hydrothermal pretreatment of barley flour can be an appropriate processing step of making naturally containing β-glucan rusks with polysaccharide molecular characteristics that are more effective in promoting the health benefits of these fibers (high molecular weight). Graphical abstract Image 1 Highlights • Flour particle size and autoclaving decrease the starch gelatinization enthalpy. • Barley flour autoclaving increases the dough elasticity, viscosity and hardness. • Reduction of barley flour d 50 value increases rusk volume and reduces hardness. • Barley flour autoclaving reduces loaf volume and increases hardness of the rusks. [ABSTRACT FROM AUTHOR]

Starch dough is a biphasic system in which the solid starch granules are dispersed in a continuous liquid matrix of binder paste. Experiencedly, the rheological nature of starch dough is vital to starch noodle production and heavily depends on the binder paste applied. The starch dough processing in the manufacture of starch noodle is widely spread but lacks scientific evidence. In the present study, the rheological behaviours of nine binder pastes and their corresponding sweet potato starch doughs were investigated by both steady shear and dynamic oscillatory shear measurements. The results showed that the processing characteristics of starch doughs were highly dependent on the binder paste applied, i.e., the doughs with binder pastes from sweet potato, cassava, potato and waxy maize starch displayed better dropping performance than that with binder pastes from pea, mung bean, wheat, rice or maize starch. Rheologically, both binder pastes and starch dough exhibit overall shear-thinning and thixotropic properties. A good binder paste could be defined by a lower thixotropy, consistency and loss modulus, as well as a higher loss tangent. For the first time, the present study performed a rheological characterization of starch dough and cast a new light on the dependence of its processing suitability on the binder paste involved. The findings herein successfully merge the experiences of starch dough processing into science. [ABSTRACT FROM AUTHOR]

Steam explosion (SE) was applied to modify the chemical-physical properties of wheat bran and the effects of SE bran on structural and rheological properties of wheat flour dough were investigated. Results showed that SE modified wheat bran by facilitating the dissolution of soluble dietary fibers (SDF) and promoting its hydration properties. Substitution of SE bran in wheat flour dough mainly caused the competitive water sequestering effect. The effect promoted the partial dehydration of gluten and caused protein conformational changes of the collapse of β-turns into β-sheet structures. These phenomena demonstrated a more polymerized and stable gluten network formed, which inevitably affected dough rheological properties. The addition of SE bran caused some changes of dough farinograph property depending on the gluten content. It improved the dough stability by increasing the development time (DT) and decreasing the softening degree (D s ) at low-gluten content, while took the adverse effects at higher gluten content owing to the excessive water sequestering and dilution action of bran. Viscoelastic profiles confirmed that SE bran strengthened the dough elasticity by increasing the storage modulus ( G′ ) and loss modulus ( G″ ) and decreasing the loss tangent (tan δ ) of dough at all gluten content. The results contribute to interpret the action mechanism of SE modification on cereals’ brans and further guide the application of SE modification on cereals' bran processing and its flour products development. [ABSTRACT FROM AUTHOR]

In the present study, the effects of pentosanase (Pn) and glucose oxidase (GOX) on the properties of whole wheat steamed buns dough were investigated, including the composition, rheology, and microstructure, to reveal the effects and mechanisms of action of these two enzymes in whole wheat steamed buns making. Compared with the Control, the dough exhibited a higher content of water extractable arabinoxylan and a stronger solubility in protein in the presence of Pn. Additionally, Pn-treated dough showed high extensibility, with the gluten matrix more open and the starch granules more visible. On the other hand, the addition of GOX decreased the number of free sulfhydryls and increased the content of glutenin macropolymer (GMP), indicating the formation of disulfide bonds. Reducing SDS-PAGE of albumin and globulin suggested the generation of large protein aggregates and the conjugation of protein-polysaccharide by non-disulfide covalent bonds. The GOX-treated dough was significantly strengthened, which generated a more continuous and highly dense gluten network. Although the effects of Pn and GOX on the dough were considerably different, they both significantly changed the rheology and microstructure of the dough, due to the solubilization of water un-extractable arabinoxylan and the increase of GMP and the formation of protein-polysaccharide conjugates. These effects observed for steamed buns could be extended to other fermented flour products. [ABSTRACT FROM AUTHOR]

The gas retention capability of dough is closely related to the terminal domains of high molecular weight glutenin subunits (HMW-GS) in gluten. In this work, the N-terminal domain of HMW-GS 1Dx5 (1Dx5-N) of hydrophobic nature was expressed in E. coli . Its aggregation induced by heating (37 °C, 50 °C, 65 °C, 80 °C) and edible salts (NaCl, Na 2 CO 3 ) was systematically investigated using circular dichroism, dynamic light scattering and size exclusion HPLC as major tools. The results revealed that heating with NaCl induced the formation of macro-molecular weight 1Dx5-N aggregates (» 670 kDa) through disulfide bond (SS) and hydrophobic interactions. Whereas heating with Na 2 CO 3 under alkaline pH broken the S-S bonds and decreased protein surface hydrophobicity, leading to the formation of relatively low-molecular aggregates (44.3–670 kDa). The interfacial property studies by tensiometry and rheometry suggest that the macro-molecular weight aggregates (» 670 kDa) negatively impacted protein capacity to reduce surface tension, nevertheless this greatly improved the formation of “gel-like” structure at the air/water surface, which would be beneficial for the gas-retention ability of wheat dough. The low-molecular aggregates (44.3–670 kDa) efficiently reduced the surface tension of 1Dx5-N, but led to the weakened interfacial layer, which could be detrimental for the gas-retention of dough. This work is the first to reveal functional difference of heating with table salt (NaCl) and alkaline salt (Na 2 CO 3 ) in the aggregation behavior and interfacial properties of the N-terminal domain of HMW-GS. This research will provide new insights into the gas retention capability of the N-terminal domain of HMW-GS. [ABSTRACT FROM AUTHOR]

A complete rehydration is essential for the functionality of hydrocolloids. Knowledge of powder-water-interactions at high concentration, i.e. sparse water conditions, allows an understanding of the competition for water under these conditions. This topic is of practical relevance for dispersing of swelling biopolymer particles and dough formation processes. This study focuses on methods to investigate properties of hydrocolloids critical to rehydration, such as viscosity development, swellability and dissolution. These characteristics determine the rehydration behavior of dry products. Special consideration was given to the dynamics of these processes. Disintegration behavior of hydrocolloid aggregates was assessed and a special rheometer set-up was constructed to demonstrate the influence of shear stress. The findings from powder characterization were used to explain dispersion experiments. Quantitative data are given for xanthan gum, guar gum and alginate. [ABSTRACT FROM AUTHOR]

Specific volume and crumb hardness, cohesiveness and porosity of gluten-free breads (GFBs) are still far from consumers’ expectations. Since additives are increasingly avoided by the consumers, a quality improvement of GFBs through the optimization of the starch source may provide important benefits. In this study, the effect of five different A-to B-type wheat starch ratios (100A-0B, 75A-25B, 50A-50B, 25A-75B, 0A-100B) on the quality of GFBs was investigated. The increase of the proportion of B-type granules (small ones) augmented the packing degree and uniformity of the continuous phase (starch-hydrocolloid matrix) as well as the Pickering effect (B-type granules being adsorbed onto the air-liquid interface), improving air bubble stabilization. In addition, 0A-100B dough displayed a more delayed crumb settling due to the higher pasting temperatures of B-type granules. Furthermore, the increase of the proportion of B-type granules also increased the apparent viscosity and viscoelastic moduli of doughs, which noticeable diminished bread expansion in 0A-100B sample. Interestingly, 75A-25B and 25A-75B doughs resulted in GFBs with the highest specific volume and crumb cohesiveness and lower crumb hardness, the former with open grain structure (fewer cells with larger size) and the latter with close grain structure (more cells with smaller size). For the first time, it is shown that a specific A-to B-type wheat starch ratio enables: 1) the simultaneous optimization of dough viscosity and Pickering stabilization to attain GFBs with improved physical quality and; 2) the modification of crumb porosity while maintaining specific volume and crumb texture. [ABSTRACT FROM AUTHOR]

An extremophilic xylanase from Aureobasidium pullulans NRRL Y-2311-1 was produced on wheat bran and its performance in bread making was investigated for the first time. Two different world-wide-used commercial xylanase preparations were also applied in bread making as comparison. Effects of different enzyme dosages on various farinograph and extensograph properties of the dough and bread quality were evaluated in detail. The novel xylanase provided increase in water absorption, development time and stability of the dough and decrease in dough softening degree and mixing tolerance index at a dosage of 100 U/100 g flour. None of the enzymes provided reasonable increase in dough extensibility. There was no direct correlation between the extensograph properties (mainly, resistance and extension) of the bread dough and the bread specific volume. A . pullulans xylanase (125 U/100 g flour) provided remarkable improvement (30%) in bread specific volume as compared to the commercial counterparts. The moisture content values of all the bread samples were within the ideal limits (35–40%). A . pullulans xylanase was the most effective enzyme in decreasing the crumb firmness. Slight improvements in cohesiveness and remarkable decline in springiness and gumminess were observed for all the enzymes tested. The results of this study provide an opportunity for A . pullulans xylanase to be used in bread making at industrial scale. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the physicochemical properties of white wheat flour pulverized by jet mill and the rheological behavior of the resultant doughs. A commercial coarse (control) wheat flour with d 50  < 75 μm (CON) was micronized by jet-mill under two different feed rates, resulting in fine and ultrafine flour preparations with d 50  < 21 μm (JM1) and d 50  < 12 μm (JM2), respectively; d 50 value was reduced with decreasing feed rate. The levels of damaged starch (5.3–11.5% as is) and water soluble arabinoxylans (0.4–0.5% d.b.) increased (p < 0.05) with reduction of flour particle size, while no changes in apparent peak molecular weight, determined by HPSEC–RI, and primary structure of the AXs (e.g. degree of branching) estimated by 1 H NMR, were noted upon flour jet-milling. Starch gelatinization properties and dough rheological behavior of CON, JM1, JM2 flours and a mixture (CON:JM1 1:1), covering a particle size range applicable to actual breadmaking processes, were studied. Calorimetry of aqueous flour dispersions (flour:water 30:70 w/w) showed a decrease in starch gelatinization enthalpy of the flours containing jet mill fractions compared to control flour. For the jet mill flours, the creep-recovery test of doughs (flour:water 56:44) revealed an increase (p < 0.05) in resistance to deformation, elasticity and zero shear rate viscosity. Additionally, Texture Profile Analysis (TPA) and compression - stress relaxation testing after lubricated squeezing flow (LSF) revealed that with decreasing flour particle size, the doughs become harder with higher consistency, more sticky and gummy and exhibit longer half relaxation time, lower relaxation rate and higher elongational viscosity. [ABSTRACT FROM AUTHOR]

Influence of carboxymethyl cellulose sodium (CMCNa) with different degree of substitution (DS = 0.5, 0.8, and 1.1) on water distribution, rheological property, microstructure, and baking performance of frozen bread dough were studied during frozen storage. Results revealed that addition of CMCNa slowed the increase of freezable water content and tanδ of dough during frozen storage, and CMCNa with high DS had more beneficial effects on inhibition the change of freezable water content and tanδ. The CMCNa weakened the influence of the frozen treatment on the water mobility and stabilized the microstructure. The bread made from frozen dough possessed larger specific volume and smaller hardness with addition of CMCNa. And the high DS CMCNa showed the most positive effect on baking quality of frozen dough during the frozen storage from 0 to 8 weeks. [ABSTRACT FROM AUTHOR]

The addition of bioactive β-glucan to gluten-free breads is of special interest to people suffering from celiac disease. Most of the studies found in literature involve cereal (1 → 3)(1 → 4)-β-glucan, while those from yeast and fungi are still nearly unexplored. This study focuses on the effect of fortifying gluten-free rice-based doughs and breads with (1 → 3)(1 → 6)-β-glucan concentrates derived from yeasts –soluble (SBG) and insoluble (IBG)– and fungi ( Pleurotus Ostreatus ) (FBG). SBG-enriched doughs were less firm and exhibited lower resistance to deformation than doughs with FBG or IBG. In contrast, FBG- and IBG-enriched doughs increased their resistance to deformation as the concentration increased. Doughs with a firmer consistency as determined by a forward extrusion test (FBG- and IBG-enriched doughs) corresponded to those with larger dynamic moduli and lower frequency dependence, lower elastic deformation and higher viscosity at steady state. The physical quality of breads was significantly improved by addition of all types of (1 → 3)(1 → 6)-β-glucan at optimized dough hydration. They caused an increase in the specific volume of the breads, a reduction in their hardness and longer shelf-life. Sensory evaluation also demonstrated an improvement in bread organoleptic attributes when SBG was added. [ABSTRACT FROM AUTHOR]

Chitooligosaccharides (COS), a group of cationic derivatives, have a number of potential applications in the food industry. However, their alleviative effects on frozen dough products have not previously been well explored. In this work, the effects of adding COS to frozen steamed bread dough later subjected to freeze–thaw (FT) treatment were systematically investigated. The results revealed that COS significantly improved the quality of frozen dough, the specific volume of the steamed bread with the addition of COS increased by 25.4% and the hardness was reduced by 5.9% compared to the control group. In addition, COS also significantly restrained the water migration and retarded the increase in the freezable water content of the dough during FT treatment (P < 0.05). After FT-4, the freezable water content of COS group was decreased by 12.5% in comparison with the control group. In addition, the COS facilitated the prevention of disulfide bond cleavage. The free sulfhydryl content of 4.46 μmol/g in the control group was significantly higher than that of other groups after FT treatment (P < 0.05), which enabled the dough to maintain its rheological properties. Moreover, dough with higher concentrations (0.15% and 0.25%) of COS exhibited better gas-holding capacity. These results revealed that COS can effectively maintain the characteristics of frozen dough, improve the quality of frozen steamed bread, and also provide new insights concerning the cationic polysaccharides used in the preparation of frozen dough. [Display omitted] • A new strategy for chitooligosaccharides to improve the quality of frozen dough was constructed. • Chitooligosaccharides improved the Specific volume and texture of frozen steamed bread. • Chitooligosaccharides inhibited water migration of frozen dough during freeze–thaw cycles. • Chitooligosaccharides interacted with gluten proteins to prevent depolymerization. • Chitooligosaccharides maintained the rheological properties of dough freeze–thaw cycles. [ABSTRACT FROM AUTHOR]

Similar to gluten, zein can form a viscoelastic network upon hydration and shear. This makes zein a promising protein to develop gluten-free bakery products. In this study, the effect of addition of different hydrocolloids (hydroxypropyl methylcellulose (HPMC), guar and xanthan gum), and the inclusion of pregelatinized starch (PG starch) and lactic acid (LA) on zein-corn starch dough and bread properties was examined. The addition of HPMC, and to a lesser extent guar gum, significantly changed the viscoelastic zein dough properties and resulted in bread samples with improved loaf volume and sensory properties. Scanning electron microscopy revealed the formation of a continuous fine foam-like structure in the zein-starch dough when HPMC and guar gum were added. This finer structure translated in a lower dough stiffness and resistance to deformation, and a higher degree of deformation characterized by lower complex moduli and increased creep compliance values. Xanthan gum addition, conversely, had an adverse effect on zein bread loaf volume which was attributed to potential weak repulsion between xanthan and zein molecules. In addition, the amount of α-helix and β-sheet secondary structures in bread samples was altered upon hydrocolloid and PG starch addition and played a role in bread crumb hardness. Overall, the zein bread with HPMC showed textural properties most similar to gluten bread. This research sheds light on different structure levels of zein-based gluten-free recipes as affected by inclusion of hydrocolloids, PG starch and LA, and provides a sound basis for the rational development of zein-based gluten-free breads. [Display omitted] • Zein forms a viscoelastic fibrillar network upon hydration and shear. • Zein-starch (Z-S) systems hold promise for gluten-free bread production. • Hydrocolloid addition alters the viscoelastic dough properties of Z-S recipes. • Hydrocolloid characteristics strongly determine protein structure in Z-S recipes. • Molecular built and microstructure of hydrocolloid Z-S dough relate to loaf quality. [ABSTRACT FROM AUTHOR]

This study examined the effects of epigallocatechin-3-gallate (EGCG) concentration on the structural hierarchy of the gluten network in dough. At micro scale, 1.0% or higher EGCG destroyed the continuity of the gluten network, which was proved by the increase of lacunarity and almost doubling at 2.0% EGCG. At nano-scale, the increase of EGCG concentration significantly (p < 0.05) raised the proportion of the bulk water and lowered the bound water, and significantly reduced the amount of glutenin macromolecule in the dough. At atomic scale, EGCG (≥0.8%) reduced covalent bonds (mainly disulfide bonds in gluten) to dis-aggregate gluten network, but significantly increased the hydrogen bonds, ionic bonds, and hydrophobic interactions to aggregate. In non-covalent bonds, the hydrophobic interaction has positively linearly correlation with the amount of EGCG, indicating that it is the main driving force for EGCG binding gluten, thereby the burial of tryptophan in the tertiary structure of gluten happened. However, at the molecular level, EGCG increased the ratio of aggregate and β-turns, and decreased α-helix in the secondary structure as well as disulfide bridge g - g - g conformation, but not significantly raised in general β-sheet. These unstable secondary structure and disulfide bridge conformation suggested gluten disaggregation caused by EGCG disruption of disulfide bonds outweighed gluten aggregation it promoted through non-covalent bonds, resulting in a loose aggregation morphology of gluten and a discontinuous gluten network. [Display omitted] • Epigallocatechin-3-gallate (EGCG) disrupted the continuity of the gluten network. • EGCG mainly bound to the gluten via non-covalent bonds. • The hydrophobic interaction was the main driver of EGCG binding to proteins. • EGCG mainly destabilized gluten by reducing the g-g-g structure of disulfide bonds. • Gluten depolymerization caused by EGCG exceeded its gluten aggregation. [ABSTRACT FROM AUTHOR]

Doughs were prepared from a single variety breadmaking flour (cv. Hereward), from three successive harvests (years; 2011, 2012 and 2013). A preparation of the aqueous phase from dough, known as dough liquor (DL), was prepared by ultracentrifugation and its physico-chemical properties were investigated. Surface tension and interfacial rheology, showed that the interface of DL was lipid-dominated and that 2013 DL had a different type of interface to 2011 and 2012 DL. This data was consistent with the improved foam stability observed for 2013 DL and with the types of lipids identified. All foams collapsed quickly, but the most stable foam was from 2013 DL with 89.2% loss in foam, followed by 2011 DL with 91.7% loss and 2012 had the least stable foam with a loss of 92.5% of the foam structure. Glycolipids (DGDG and MGDG) were enriched in 2013 DL, and were also present in DL foam, contributing towards improved stability. Neutral lipids, such as FFAs, were enriched in DL foams contributing towards instability and rapid foam collapse. Baking trials using 2012 and 2013 flour, showed increased loaf volumes and gas bubble diameter in 2013 bread compared to 2012 bread, highlighting the potential impact that surface active polar lipids, enriched in the aqueous phase of dough, could have on improving breadmaking quality. [ABSTRACT FROM AUTHOR]

The present review analyzes the effect of the most common hydrocolloids on diverse aspects of wheat breadmaking. This encompasses exudate gums, gums from seaweeds, modified celluloses, pectins, galactomannans from leguminous seeds and exopolysaccharides from microbial fermentation. Hydrocolloids are employed to improve dough performance, bread characteristics and sensorial quality. They are also added to minimize non desired changes in crumb texture during storage (anstistaling effect). In bake off technologies (frozen dough, par-baked bread) they can help to preserve the structure from damage by freezing thus rendering acceptable products. Finally, nutritional improved mixtures of wheat and other flours can take advantage from hydrocolloids addition in order to compensate a diminished quality. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose (BNC) is an emerging nanomaterial with a morphologic structure of a 3-D network and unique properties produced by several species of bacteria. The objective of the present work was to evaluate whether the addition of BNC improved the baking quality of wheat flours, making a change in the viscoelastic behavior of the mass. A study of the rheological behavior of wheat bread dough containing BNC was performed by thermo-rheological and isothermal dynamic oscillatory experiments. The baking response and bread quality parameters were also analyzed. BNC increased specific volume, and moisture retention, decreasing browning index. Although BNC produced both raw and heat-treated doughs with more elastic characteristics, textural studies revealed that the addition of BNC reduced firmness of bread crumb. Confocal laser scanning microscopy observations showed differences in gluten filaments between control and BNC crumb samples that could explain the larger average porous size of BNC crumb. BNC could be used as improver in the bread-making performance. [ABSTRACT FROM AUTHOR]

Zein forms viscoelastic network with water to support the weak structure of gluten-free dough, but which requires temperature above 40 °C. A new method preparing zein network at room temperature using food-grade acetic acid was reported in our previous research. The current research explored the influence of zein network containing acetic acid on the rheology, texture, and tensile properties of rice gluten-free dough, as well as the interaction between zein network and rice flour. Results showed that zein network could act as a structural support material by binding rice flour particles to transmit its viscoelasticity and extensibility to rice dough, thus enhancing the ability of rice dough to resist external forces. The structural characteristics of zein-rice dough were both zein network-dependent and rice flour-dependent. α-Zein network could mix with rice flour particles more evenly than total-zein (T-zein, comprising α-, β- and γ-zein) network due to the thinner and denser fiber bundles, so the stretchability and thermal stability of α-zein-rice dough were greater than that of T-zein-rice dough, and the cooking loss of α-zein-rice noodle was less than that of T-zein-rice noodle. Compared with japonica rice dough and indica rice, waxy rice had less amylose, so the elasticity of zein-waxy dough was weaker than that of zein-japonica dough and zein-indica dough. And the gel network formed by amylose in rice during heating increased the elasticity of zein-rice dough. Additionally, the interaction between zein network and rice flour increased the ordered structure of starch in rice flour. [Display omitted] • Zein network increased the ordered structure of starch in rice flours. • Zein network could improve the structural defects of rice dough. • Zein network increased the viscosity and decreases the elasticity of rice dough. • Zein network could give the rice gluten-free dough with extensibility. [ABSTRACT FROM AUTHOR]

To clarify the correlations between dough rheology and gluten aggregation, the rheological properties of low-sodium salt dough, the molecular chain morphology, molecular weight, subunit distribution and molecular conformation of dough gluten were investigated in this paper, and these results were compared with those of NaCl and KCl alone. Results showed that hardness, extensibility and compression resistance of low-sodium salt dough were enhanced, and the doughs were more like viscoelastic solid material. Atomic force microscopy images showed that low-sodium salt induced the combination of gluten peaks to form the larger protein clusters. Size exclusion/reversed phase-high performance liquid chromatography profiles suggested that low-sodium salt increased the content of B/C-low molecular weight glutenin subunits and high molecular weight glutenin subunits by reducing the content of α- and γ-gliadin, and mediated gluten aggregation to a certain degree. Besides, fluorescence spectra demonstrated low-sodium salt changed the conformation of gluten molecules. In summary, the improvement of rheological properties of low-sodium salt dough could be caused by the aggregation of low-sodium salt and dough gluten. Correlation analysis revealed that rheological properties of low-sodium salt doughs were highly related to the content of gliadin and glutenin fractions. NaCl and KCl also presented similar effects. Among the three salts, NaCl had the most prominent effect, followed by low-sodium salt. This study provides new insights and more comprehensive theoretical basis for sodium reduction. [Display omitted] • Low-sodium salt doughs were more like viscoelastic solid material. • Low-sodium salt enhanced the strength and extensibility of dough. • Low-sodium salt induced gluten peak binding to form larger protein clusters. • Low-sodium salt mediated dough gluten aggregation to some extent. • Low-sodium salt changed the conformation of gluten in dough. [ABSTRACT FROM AUTHOR]

The effects of four kinds of potassium- (potassium alginate, PA; potassium dihydrogen phosphate, KDP) and calcium-based (calcium carbonate, CC; calcium silicate, CSi) compounds on the pasting behavior, rheological properties, microstructure, water mobility, and textural characteristics of pastes, dough, and high-moisture starch hydrogels from potato starch were evaluated. The results showed that the addition of 0.5% CSi, 0.5% CC, 0.4% PA and 0.4% KDP (w/w, total starch basis) significantly improved the tensile strength of high-moisture starch hydrogels compared to that of pure potato starch. Further discussion about the mechanism revealed that the addition of these components could reduce the swelling capacity and peak viscosity of potato starch during heating, further enhance the network structure of the starch dough, and reduce the water mobility thereof, thus contributing to a compact stacking of starch and smaller and denser pore structure of the high-moisture starch hydrogels. This study provides a theoretical basis for the formulation design of alum-free hydrogel derived products. [Display omitted] • The mechanism of high-moisture starch hydrogels quality formation was investigated. • Potassium- and calcium-based components improved the heat stability of potato starch. • Potassium- and calcium-based components contributed to the dense dough network structure. • High strength starch dough could form a hydrogel with higher tensile strength. [ABSTRACT FROM AUTHOR]

Concerned to chemical structure, the viscous gamma-polyglutamic acid (γ-PGA) should have the similar characteristics with antifreeze hydrocolloids and polypeptides which have been broadly used in frozen foods. However, the cryoprotective functions of γ-PGA are little explored as compared to those of hydrocolloids and polypeptides. In this study, influences of γ-PGA addition on fermentative performance and rheological behavior of frozen steamed bread (SB) dough during frozen storage and freeze–thaw cycles were investigated, and the underlying mechanism governing these influences was clarified. Results showed the γ-PGA dispersed free water, remarkably reduced freezable water content, and restricted water migration, which facilitated the formation of smaller and more uniform ice crystals in frozen dough structure. In addition, γ-PGA interacted with gluten proteins through electrostatic attractions and hydrogen bonds, transforming the gluten protein conformation from loose coil structures to relatively compact β-structures. In these relatively compact structures, the free sulfhydryl (SH) groups, originally located far away in space, became closer and easier to be oxidized into disulfide bonds (SS) or be involved in SH–SS exchange reaction. This led to intensive protein aggregations and water–solid interplay, rendering the dough better resilience to cope with ice growth and recrystallization. Accordingly, the deterioration in frozen SB dough's fermentability and rheology was effectively alleviated, suggesting that γ-PGA has a great potential to serve as an effective cryoprotectant in frozen SB. [Display omitted] • Gamma-polyglutamic acid (γ-PGA) lowered melting temperature of frozen dough. • γ-PGA reduced freezable water and restricted water migration in frozen dough. • γ-PGA interacted with gluten protein via electrostatic attraction and hydrogen bond. • γ-PGA alleviated depolymerization of glutenin macropolymers in frozen dough. • γ-PGA improved fermentability and viscoelasticity of frozen dough. [ABSTRACT FROM AUTHOR]

This study compared the deterioration of pre-fermented frozen dough in 1–90 days frozen storage (FS) and 1–4 times of freeze–thaw cycles (FT) by analysing the characteristics of steamed bread, its dynamic rheology and rheofermentation properties, gluten aggregation, yeast viability, cell microstructure and yeast metabolites. The results showed that the specific volume and hardness of steamed bread after 25 days of FS and 1 FT were unacceptable. The decrease in the elasticity modulus and the increase in the viscosity modulus caused by FT were more obvious than those caused by FS. The rheofermentation results indicated that both FS and FT decreased the gas retention and gas production ability, but more significant negative effect was observed during FT than during FS. Further investigation of the gluten aggregation showed that the glutenin macropolymer decreased during FS and FT whether yeast was added or not to the dough, and the yeast increased the decline rate from 0.24 to 0.52 when FT was conducted, which indicated that the yeast had a negative effect on gluten aggregation. The yeast viability and microstructure showed no significant difference during FS and FT, whereas the yeast metabolites results demonstrated that the glucose and fructose contents increased during FS but decreased during FT, which indicate a difference in yeast metabolism. Fructose and glucose could be the indicators of the difference in the deterioration mechanism of FS and FT based on the factor analyses. This study provided novel insights on the deterioration mechanism of pre-fermented frozen dough. [Display omitted] • Elasticity and gas retention of frozen dough decreased more during freeze-thaw than frozen storage. • Yeast increased the decline rate of glutenin macropolymer in frozen dough. • Yeast metabolism was related to the deterioration mechanism of frozen dough. • Glucose and fructose increased during frozen storage, but decreased during freeze-thaw. [ABSTRACT FROM AUTHOR]

Gluten–starch interactions are of specific importance during processing of cereal-based products. They become especially relevant during heating because of heat-induced changes within these biopolymers. A comprehensive characterization of the interactions during heating of the starch–gluten model dough based on its mechanical behavior taking into account its raw material ratios and dough adapted water additions has yet to be achieved. Thus, the macrostructural characteristics with varying starch–gluten ratios (92:8, 89:11, 86:14, 83:17, 80:20) in combination with different water additions (57.77, 60.78, 63.78, 65.58, 69.11 g water 100 g −1 blend) was analyzed in dynamic oscillatory study during heating from 30 to 98 °C. The delayed gelatinization onset (+7 °C) with increasing gluten content could be referred to a barrier effect of gluten around the starch granules with a hindered diffusion of water into the granules, since a competitive hydration was not significantly detectable. The decreased gelatinization intensity (−67%) due to an increased gluten content showed a negligible effect of the barrier effect and a more competitive hydration between gluten and starch. A further reason can be weakening zones in the leached amylose network and a hindered granule–granule interaction. Moreover, a simple possibility to identify the gelatinization onset in oscillatory tests by the derivative of the loss factor was defined. [ABSTRACT FROM AUTHOR]

Whole wheat flour dough (WWFD) has a high content of dietary fibres that causes a negative influence on the dough rheology, resulting in undesirable quality for whole wheat bread (WWB). Therefore, to devise the processing strategies for overcoming the quality issues for WWB is of remarkable significance. The cooperative fermentation by yeast and lactic acid bacteria (CFYL) has been proposed as a powerful processing technology to modify the dough rheology, retention and stabilization of gas cells for a WWFD. The breadmaking performance of WWFD has been modified due to the CFYL-induced changes in the structure of wheat bran, gluten proteins and wheat starch. CFYL mitigated the negative influence of wheat bran on gluten network. CFYL also strengthened the intermolecular interactions between proteins and starch. During CFYL, exopolysaccharides (EPSs), enzymes and organic acids were produced which modified the dough rheology and led to an improvement in the bread quality. Moreover, CFYL contributed to an increase in the water-extractable arabinoxylans and soluble wheat proteins but a decrease in the starch granule sizes. This results in a higher strain hardening and a stronger liquid film of the dough for improving the retention and stabilization of gas cells in a WWFD during breadmaking. As such, CFYL has a good potential use for WWB manufacturing to achieve the products with desirable overall quality and satisfactory consumer acceptability. [Display omitted] • Cooperative fermentation by yeast and lactic acid bacteria (CFYL) is useful. • CFYL induced structural changes in bran, gluten and starch. • CFYL produced exopolysaccharides, enzymes and organic acids. • Whole wheat flour dough (WWFD) rheology was modified by CFYL. • CFYL improved the retention and stabilization of gas cells in a WWFD. [ABSTRACT FROM AUTHOR]