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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. [ABSTRACT FROM AUTHOR]

Featured Application: The obtained results may be applied in gluten-free bread production. Inulin may be widely used in in the food industry due to its many health benefits. It has the potential to increase the insufficient nutritional quality of gluten-free bread. Therefore, the aim of this study was to test the applicability of inulin in rice baking. The impact of added inulin (5%, 10%, 20%, 30%, and 40%) on the dough's rheological, bread's textural and sensory characteristics was evaluated. The extensibility of rice dough during uniaxial deformation tests (8.5 mm) was improved by the added inulin (10.2–12.3 mm). The presence of inulin softened the dough and shifted the gelatinization temperature toward higher values. The added inulin also increased the loaf's specific volume (1.16–1.48 mL/g), tenderized the breadcrumbs, increased the crumb porosity (36–58%), and generally improved the crumb structure. The panelists favored the sensory characteristics of breads with inulin. However, baking losses were increased in these breads as well (15.1–18.5%). The effect of the added inulin on the dough and bread characteristics generally rose with an increasing addition of inulin, reaching the maximum in samples with 30% inulin. The presence of 40% inulin deteriorated some characteristics of the bread. Therefore, the addition of up to 30% of inulin seemed to be optimal for rice bread. [ABSTRACT FROM AUTHOR]

Tannic acid (TA) has been recently considered as a new dough additive for improving the bread-making quality of wheat. However, the effects of TA supplementation on the sensory quality parameters (color, crumb grain structure, and sensory properties) of bread have not been studied. Further, the potential of TA supplementation in bread-making quality improvement has not been evaluated by using commercial flour. In the present study, three commercial wheat flours (namely, XL, QZG, and QZZ) with different gluten qualities were used to evaluate the effects of TA supplementation (in concentrations of 0.1% and 0.3%, respectively). TA supplementation did not change the proximate composition of the breads but increased the volumes and specific volumes of XL and QZG breads. TA supplementation enhanced antioxidant activities, with 0.3% TA significantly increasing the antioxidant capacities of bread made from all three flour samples by approximately four-fold (FRAP method)/three-fold (ABTS method). Positive effects of TA on the reduction in crumb hardness, gumminess, and chewiness were observed in the XL bread, as determined by the texture profile analysis. For the analyses on visual and sensory attributes, our results suggest that TA did not affect the crust color, but only slightly reduced the L* (lightness) and b* (yellowness) values of the crumb and increased the a* (redness) value. TA supplementation also increased the porosity, total cell area, and mean cell area. Satisfactorily, the sensory evaluation results demonstrate that TA-supplemented breads did not exhibit negative sensory attributes when compared to the non-TA-added breads; rather, the attributes were even increased. In summary, TA-supplemented breads generally had not only better baking quality attributes and enhanced antioxidant activities, but, more importantly, presented high consumer acceptance in multiple commercial flour samples. Our results support the commercial potential of TA to be used as a dough improver. [ABSTRACT FROM AUTHOR]

This article explores the use of unconventional herbal raw chia seeds. We studied bread made from whole wheat and rye grains with the addition of moistened chia seeds. According to the recipe for making bread, an optimal sample of bread was selected, all indicators of the quality of the dough and finished bread were determined. According to the results of the study, a sample with the addition of 10% chia seeds as an additive to the wheat dough was chosen as the most optimal option. In general, it was found that the consistency of a semifinished product prepared from the optimal variant, in terms of dryness and in general, in terms of rheological properties, does not impair the quality of the finished bread. According to the research data, in the optimal variant, the content of antioxidants is higher than in the control sample. In the raw materials used, the amount of starch is less, and the presence of proteins is greater, based on this, the total starch content decreases, this helps to slow down the hardening of bread, which is proved by the research results.

Amaranth flour from germinated (GA) and non-germinated (A) seeds (0%-C, 5%, 15%, 25%) were mixed with wheat flour for breadmaking. Fermentation parameters of dough (time-tf, maximum volume-Vmax) were obtained. Specific volume (Vsp) of breads, crust color, texture and relaxation of crumb were analyzed. A high amount of germinated amaranth flour decreased Vmax and increased tf, obtaining breads with low Vsp and darkness crust. A firmed and chewy crumb, although with a more aerated structure (high area occupied by alveoli) was obtained. The GA25 bread presented the softer crumb. The elastic modulus-E1 of crumb increased and the relaxation time-T1 decreased with higher amounts of amaranth flour, suggesting the formation of a more structured crumb; mainly in the case of non-germinated amaranth flour. Wheat flour resisted the inclusion of 25% of germinated amaranth seeds (GA25) without substantial changes in bread quality. [ABSTRACT FROM AUTHOR]

Within the flour wheat genetic improvement program, bakery quality as a selection criterion is delayed and expensive, so variables that help to select it indirectly must be identified. The objective of this research was to relate the kneading variables in whole wheat flour with the industrial characteristics of the doughs and their volume of bread in refined flour. Protein content and sedimentation volume in refined flour, kneading time and stability, kneading tolerance and mixogram height in whole and refined flour, dough strength, tenacity-extensibility relationship and bread volume in refined flour were measured. The average value and Pearson correlations were obtained, genotypes were classified based on their bread volume, and an average comparison was made. The volume of bread was positively correlated with kneading time in whole meal flour (0.6). In addition, the stability to kneading in whole meal wheat flour was correlated with kneading time in refined flour (0.5) and dough strength (0.5). Bread volumes greater than 800 cc had kneading times of 2.4 to 2.9 min in whole flour. So, the use of time and stability of kneading in whole meal flour would help to efficient the selection of genotypes with masses of baking characteristics. [ABSTRACT FROM AUTHOR]

To study the effect of quinoa and canahua wholemeals on wheat flour quality, addition dosages of 10 and 20% wt. were tested. Both non-traditional materials lowered protein baking quality (Zeleny sedimentation), and present dietary fibre increased the Falling number. The fermentograph and maturograph tests showed differences in the optimal fermentation and proofing times, as well as in dough volumes during both tests (which were somewhat higher for the wheat-quinoa flour composites). Besides this, dough volumes in the third stage of fermentation simulated on the oven-rise apparatus decided about baking trial results; in this regard, wheat-canahua flour composites reached statistically better results. All obtained data together with sensory scores pointed to the maximal tolerable quinoa or canahua dosage up to 15% wt. [ABSTRACT FROM AUTHOR]

Strain hardening of wheat flour (WF) proteins during fermentation and baking is at the basis of the excellent quality of wheat breads. Yet, there are good reasons to use rye flour (RF), such as its high content of dietary fiber and other bioactives. However, rye proteins lack the ability to form dough with sufficient strain hardening capacity under extension, which partially explains the inferior quality of rye breads. A promising strategy to make high-quality breads with high nutritional value is the use of WF and RF blends. Despite this, the rheological behavior of WF/RF bread doughs has not yet been investigated. This study examines their rheology by non-linear uniaxial extensional and small-amplitude oscillatory shear measurements, and relates these measurements to the quality of the resulting breads. The strain hardening index (SHI), derived from extensional measurements, is expressed as the transient extensional viscosity at maximum strain [ηe+(εmax)] relative to the linear extensional viscosity extrapolated to maximum strain [ηe0+(εmax)]. Both the SHI and bread volume decreased when the level of RF in the blend increased. As an example, replacing 60% WF by RF led to a relative decrease of the SHI and bread volume of 34 and 64%, respectively. The decrease of the SHI is correlated to an increase in ηe0+(εmax). Comparison of the extensional curves of doughs made with blends of WF and RF and doughs made with blends of WF and wheat starch (WS) further revealed that RF components play a major role in the rheology of the doughs. In conclusion, it was found that WF/RF blends need to contain at least 60% WF to obtain bread of proper quality. [ABSTRACT FROM AUTHOR]

Water-extractable cereal flour constituents influence bread loaf specific volume, suggesting a contribution to gas cell (de)stabilization in dough. However, the underlying mechanism remains largely unexplored. We studied the impact of incorporating five cereal flour aqueous extracts in model gluten-starch bread (doughs) on specific volume, dough extensional rheology, and protein extractability changes during bread making. Incorporating wheat, rye, or triticale flour aqueous extracts in gluten-starch doughs increased bread specific volume by 12–17%. There were no changes in dough rheology that could explain this specific volume increase, suggesting that other mechanisms relating to gas cell stabilization might be at play. Incorporating oat flour aqueous extracts decreased bread specific volume by 50%. This negative impact was related to poor dough strain hardening behavior, in turn probably explained by disruption of intermolecular glutenin disulfide bonds, as revealed by chromatography. While this study has provided a novel perspective on the mechanisms by which water-extractable cereal flour constituents influence bread volume, it also demonstrates that the compositional heterogeneity of the flour aqueous extracts needs to be addressed to allow an even better understanding of the role of water-extractable cereal flour constituents in stabilizing gas cells in bread dough. [Display omitted] • Wheat, rye, and triticale flour extracts increased gluten-starch bread volume. • Changes in dough extensional rheology did not explain this bread volume increase. • Wheat, rye, and triticale extract proteins might adsorb at gas cell interfaces. • Oat extracts decreased gluten-starch bread volume. • Doughs with oat extract strain hardened less and had less glutenin disulfide bonds. [ABSTRACT FROM AUTHOR]

New strategies for a reliable assessment of baking quality of wheat are required since the protein content is a widely discussed indicator in this respect. In this study, the indicator value of the protein content for baking quality was evaluated using almost 600 wheat samples representing different quality and varieties. NIRS calibrations were developed to estimate bread volume at different levels of processing. Bread volume increased with increasing protein content in a wide curvilinear relationship with an R 2 of 0.59. At protein contents above 12% representing the relevant range for trading, the R 2 dropped to 0.15. Different wheat varieties showed differential responses (i.e. linear and non-linear) in bread volume to increasing protein content. The performance of NIRS calibrations for bread volume were best at the processing level of dough (R 2 0.81) and good at the level of whole grains (R 2 0.70). Hence, the protein content is not a reliable indicator for baking quality on its own. Bread volume was predicted better by NIRS calibrations than by protein content. A strategy is presented paying attention to the variety specific interplay between baking quality and protein content with implications for the variety registration system, trading, breeding and nitrogen fertilisation. [ABSTRACT FROM AUTHOR]

Samples of seven winter wheat cultivars, grown in several environments contrasting in N availability in 2013-2015, were analysed for grain protein concentration (by Perten Infrared analyser), and for two bread-making parameters estimated by Reomixer. Differences between cultivars in the response of bread volume and dough strength to grain protein concentration, as measured by the slope (b) of the linear regression were significant when tested against the variance of interaction Cultivars*Years. The regression coefficients (b) were not significantly correlated with the average values of the quality parameter (with the exception of the correlation between peakheight and the slope of its regression on protein concentration, which was significant in one of three years). This suggests that breeding for ensuring suitable bread-making quality with relatively lower protein content of the grain, based on studying the regression of bread-making parameters on grain protein concentration, might be feasible. [ABSTRACT FROM AUTHOR]

The baking performance and gas retention capacity of wheat dough depends on production rate and total volume of CO 2 during fermentation. This study aims to examine the effect of the CO 2 formation kinetics and the gas volume fraction on the structural integrity of wheat dough and the resulting bread quality. The gas release characteristics were evaluated using a rheofermentometer with varied concentrations of compressed yeast and instant dry yeast (CY and IDY respectively). For this purpose, the maximum CO 2 formation rate was calculated through the derivation of hydrostatic pressure curves measured in the rheofermentometer. For CY, the time when gas escapes the dough matrix (Tx, time of porosity) as well as the corresponding gas volume depended on the gas formation rate, whereas the gas retention capacity of wheat dough leavened with IDY was not affected by the CO 2 formation rate. Although the dough leavened with IDY showed improved extensibility during fermentation, the specific bread volume was 21% below that of the samples leavened with CY. These results indicate that an increase in the maximum gas formation rate considerably affects the structural integrity of the dough matrix. Because of the reduction of the loaf volume, the effect is reinforced by the application of IDY. [ABSTRACT FROM AUTHOR]

Abstract: A quality characteristic of bread is that it has a homogeneous and fine crumb structure. The latter depends on the number and size of gas cells present in dough as well as their stabilization during fermentation and baking. Discontinuities in the gluten–starch matrix result in liquid films formed from the dough aqueous phase taking over gas cell stabilization. This is especially important in late fermentation. How fermentation affects (the composition and properties of) the dough aqueous phase is unclear. In the present study, the dough's aqueous phase was isolated as dough liquor (DL) from unfermented and fermented dough made from flour and water (with or without added sugar and salt). Fermentation increased DL yield and changed its composition. With regards to surface active proteins, especially the extractability of α-amylase/trypsin inhibitors and puroindolines (PINs) in DL increased. More foam of higher stability was formed from DL from (defatted) fermented dough than from that from (defatted) flour-water dough. PINs were specifically enriched in foam from DL from fermented dough. Finally, supplementation of dough with the latter DL sample yielded bread with finer gas cells than those of control bread. Thus, fermentation enhances the foaming properties of DL, which is also translated in improved bread quality. [Copyright &y& Elsevier]

Abstract: Creep-recovery measurements were used to analyze the non-linear viscoelastic properties of wheat flour. First the effect of creep time, recovery time and shear stress was investigated on the non-linear viscoelastic properties of Bussard dough. The Burgers model was fitted to the creep and recovery curves. A linear increase of maximum creep compliance was observed with increasing creep time. On the other hand, maximum recovery compliance remained constant but an increase of the retardation time was observed which indicates a slower recovery. A recovery time of 10min seemed to be sufficient to obtain most of the recovery. Maximum creep compliance increased proportionally with increasing shear stress until a plateau was reached. Maximum recovery was constant between 100 and 500Pa but the speed of the recovery increased as shear stress increased. Finally, the optimised creep-recovery methodology was used to analyze the non-linear viscoelastic properties of 17 pure wheat cultivars. By applying principal component analysis, it was possible to identify three groups of wheat cultivars with similar rheological properties and bread volumes. [Copyright &y& Elsevier]

Abstract: This study compares the effects of freezing temperature and rate as well as storage temperature and time on the quality of frozen dough. Yeasted bread dough was frozen using four freezing rates (19–69°C/h), then stored at −10, −20, −30, or −35°C for up to 180 days. Dough strength diminished with longer storage time and higher storage temperatures. Cryo-SEM showed that dough stored at −30 and −35°C had the least damaged gluten network. NMR studies showed that more rapidly frozen dough, and that stored at lower temperatures had lower transverse relaxation (T 2) times (9–10ms). However, dough stored at −20°C displayed the highest yeast activity among samples. Bread loaf volume decreased with storage time, and bread made from dough stored at −20°C showed the highest loaf volume. Breads produced from −30 and −35°C stored dough displayed less change in the texture profile during storage as well as less change in T 2 values. Response surface analysis showed that optimal properties occurred at freezing rates of around 19–41°C/h and storage temperatures of −15 to −20°C. [Copyright &y& Elsevier]

Abstract: The combined effects of dough freezing rate, storage temperature and time on bread quality were studied. Yeasted bread dough was frozen using four freezing rates, and stored between −10°C and −35°C for up to 180 days. Dough stored at −10°C or −20°C and frozen at 18–39°C/h resulted in higher specific volume and softer bread, but higher rates of staling, and was related to relatively high yeast activity. NMR studies showed that while frozen dough stored at −30°C or −35°C produced bread with lower volume, it also had reduced staling rates. Crust color was lighter and more uniform for slower frozen dough stored at −10°C or −20°C. Longer frozen dough storage produced darker, less uniform colored crust. Increased understanding of the combined effects of processing conditions is essential for producing better quality dough and bread. This research demonstrated that specific combinations of freezing rates and storage conditions contribute to better bread quality and staling. [Copyright &y& Elsevier]

Vital gluten is often used in baking to supplement weak wheat flours and improve their baking quality. Even with the same recipe, variable final bread volumes are common, because the functionality differs between vital gluten samples also from the same manufacturer. To understand why, the protein composition of ten vital gluten samples was investigated as well as their performance in a microbaking test depending on the water content in the dough. The gluten content and composition as well the content of free thiols and disulfide bonds of the samples were similar and not related to the specific bread volumes obtained using two dough systems, one based on a baking mixture and one based on a weak wheat flour. Variations of water addition showed that an optimal specific volume of 1.74–2.38 mL/g (baking mixture) and 4.25–5.49 mL/g (weak wheat flour) was reached for each vital gluten sample depending on its specific water absorption capacity. [ABSTRACT FROM AUTHOR]