Higher Loaf Volume Research Articles

Introducing new wheat milling passages to manage the ultra-fine flours of primary streams: Roles of granulation in starchy content

The size distribution of ultra-fine flours (UFF) is crucial for determining the physicochemical properties of the final wheat milling product. To optimize the milling process, new passages with a stack of fine mesh sieves are used. The UFF extracted from both break and reduction passages exhibits a wide range of functionality and physicochemical characteristics, were incorporated into five reconstituted flour blends. By splitting of UFF fraction isolated from primary passages, the quality of baked bread can be modified manually without using any enzymes or chemical improvers. Substituting the default milling stream with 60% of primary UFF increases the availability of starch for gelatinization by shifting the peak temperature to a higher number. This creates stronger starch-gluten network exhibiting increased elasticity. Raised viscoelasticity and hence water absorption value result in higher loaf volume. The infrared spectroscopy analysis revealed a specific peak at 1659 cm−1, associated with water absorption in the amorphous region of starches, which was recorded as the highest intensity for UFF reduction samples. These results were in agreement with imposing a higher starch damage. Furthermore, structural amorphization was also observed based on a broader shallow XRD curve for samples incorporated with UFF of reduction passages due to higher grinding strength generated through the smooth rolls. The lowest polydispersity index content was calculated for break UFF samples and more uniformity in particle size distribution was found. This finding highlighted the effective role of corrugated rolls for producing the certain range of flour granulation.

Microwave-treated rice flour halves the need of hydroxypropyl methylcellulose in the formulation of gluten-free bread

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.

The entrainment and evolution of gas bubbles in bread dough—A review

AbstractBackground and ObjectiveFor control of bread quality to achieve high loaf volume and uniform crumb structure, gas bubble dynamics in dough needs to be better understood throughout different breadmaking processes. The objective of this review was to establish a solid theoretical basis on how flour type, water and salt content, and mixing conditions affected the incorporation, evolution, and stabilization of gas bubbles in a dough.FindingsBubble dynamics including entrainment, disentrainment, break‐up, disproportionation, growth, and coalescence were outlined and their effects on the gas phase of the dough were assessed. The application, advantages, and disadvantages of microscopy, magnetic resonance imaging (MRI) and X‐ray microtomography techniques for qualitatively or quantitatively characterizing the void fraction and bubble size distribution (BSD) in the dough at various stages of the breadmaking process have been discussed.ConclusionsSince the BSD evolution in bread dough is associated with the quality of the resultant products, to devise strategies for improving the product quality, dough formulation, and mixing conditions need to be considered.Significance and NoveltyDue to the obvious challenges of monitoring the fast evolution of BSD in yeasted dough, future research needs to focus on the effects of yeast activity on dough's BSD.

Effects of different types of electrolyzed waters on rheological characteristics of dough and quality properties of bread.

Water is an ingredient of considerable importance in bread dough. Effects of four different types of electrolyzed water (Anolyte NaCl, Catholyte NaCl, Anolyte Na2CO3, Catholyte Na2CO3) on quality characteristics of bread were investigated. For this aim, rheological and textural analysis of bread doughs and color, physical properties, water activity, moisture content, antioxidant activity, total phenolic content, texture profile analysis, and micrographic analysis of bread samples were performed. Electrolyzed water affected quality characteristics of dough and bread samples significantly (p < 0.05). Anolyte Na2CO3 increased the water-holding capacity of the dough from 60 ± 0.05 to 66 ± 0.07. The bread samples prepared with Anolyte Na2CO3 (363 ± 1.70) and Catholyte Na2CO3 (346 ± 1.61) electrolyzed water has higher loaf volume than the bread samples prepared with Anolyte NaCl (320 ± 1.00) and Catholyte NaCl (310 ± 1.52) electrolyzed water and control bread (270 ± 1.04) (p < 0.05). Electrolyzed water also increased the antioxidant activity (23.62 ± 0.05% inhibition) and total phenolic content (460.61 ± 2.12 GAE/100 g) of bread samples. The results of this study may be evidence that using electrolyzed water can improve the quality characteristics of bread.

Ripening rice grains under low temperature for the high loaf volume and slow firming of gluten-free rice bread without additives

Low specific volumes and high firming rates are major issues in the preparation of gluten-free rice bread. Herein, we discovered that flour acquired from rice grains ripened under lower temperatures improved the specific volume and firming rate of the resultant gluten- and additive-free rice bread. Two cultivars with different amylose contents were grown during three growing seasons (early, normal, and late) over two years (2016 and 2017). The temperatures during grain filling ranged from 22.0 to 30.1 °C, and the small differences observed between the average particle sizes and the damaged-starch contents of the samples indicated that their grain-filling temperatures had minimal influence on their flour properties. There were significant negative correlations between the grain-filling temperatures and the amylose contents or ratios of short amylopectin chains of the rice-flour samples. The bread loaf volumes were influenced by their amylose contents, not by their amylopectin structures, and correlated negatively with the grain-filling temperatures. Inversely, the bread-firming rates during storage were influenced predominantly by their amylopectin structures, and positively correlated with the grain-filling temperatures. These results indicate that rice grains ripened under lower temperatures are desirable, and that the grain-filling temperature can be an indicator of the firming of gluten-free rice bread.

Increasing the Versatility of Durum Wheat through Modifications of Protein and Starch Composition and Grain Hardness

Although durum wheat (Triticum durum L. ssp. durum Desf.) has traditionally been used to make a range of food products, its use has been restricted due to the absence of the D-genome glutenin proteins, the relatively low variability in starch composition, and its very hard grain texture. This review focuses on the manipulation of the starch and protein composition and modification of the hardness of durum wheat in order to improve its technological and nutritional value and expand its utilization for application to a wider number of end products. Starch is composed of amylopectin and amylose in a 3:1 ratio, and their manipulation has been explored for achieving starch with modified composition. In particular, silencing of the genes involved in amylose and amylopectin synthesis has made it possible to isolate durum wheat lines with amylose content varying from 2–3% up to 75%. This has created opportunities for new products with different properties and enhanced nutritional value. Durum-made bread has generally inferior quality to bread made from common wheat. Attempts to introduce the Glu-D1 subunits 1Dx5 + 1Dy10 and 1Dx2 + 1Dy12 produced stronger dough, but the former produced excessively strong, inelastic doughs, and loaf volume was either inferior or not affected. In contrast, the 1Dx2 + 1Dy12 sometimes improved bread loaf volume (LV) depending on the glutenin subunit background of the genotype receiving these genes. Further breeding and selection are needed to improve the dough extensibility to allow higher LV and better texture. The versatility of durum wheat has been greatly expanded with the creation of soft-textured durum via non-GMO introgression means. This soft durum mills like soft hexaploid wheat and has similar baking properties. The pasta quality is also not diminished by the soft-textured kernels. The Glu-D1 locus containing the subunits 1Dx2 + 1Dy12 has also been introgressed to create higher quality soft durum bread.

In situ production of vitamin B12 and dextran in soya flour and rice bran: A tool to improve flavour and texture of B12-fortified bread

This study aimed to develop a fermentation process that allows the concomitant production of dextran (a texture-enhancing agent) and vitamin B12 (in situ fortification) for bread applications. Mixed fermentation of soya flour or rice bran using Propionibacterium freudenreichii DSM 20271 and Weissella confusa A16 with added sucrose resulted in substantial quantities of dextran (5.6–5.8% dry matter) and B12 (7.9–8.9 μg/100 g fresh weight), together with antifungal metabolites (e.g. acetic and propionic acids). In addition to an extended mould-free shelf life, the bread containing 50% (dough weight) fermented soya flour or rice bran not only contained adequate levels of B12 but also exhibited improved texture and sensory quality compared to the control, such as a higher loaf volume, a softer crumb, and a more cohesive and moister mouthfeel. The mixed fermentation reduced the beany or cooked-rice flavour but increased sour and cheesy flavours and aftertaste. Dextran produced during the fermentation process exhibited a masking effect on the beany and sour notes and aftertaste, consistently with reduced levels of green or grassy volatiles (e.g. hexanal, heptanal, (E,E)-2,4-decadienal, and 2-pentylfuran). Overall, the mixed fermentation method using P. freudenreichii DSM 20271 and W. confusa A16 showed potential for B12 fortification of bread products with high sensory quality.

Significance of milling methods on brown teff flour, dough, and bread properties.

Teff (Eragrostis tef) has gained wide popularity mainly attributed to its gluten-free nature catering the needs of gluten-sensitive population. The higher water absorption capacity and gelling properties of teff flour promote its food applications, especially in the baking sector. The nutritional and sensorial properties of teff flour have been studied by incorporating with wheat flour at different proportions, but no study has reported the impact of various milling methods on the rheological and bread-making properties of teff flour. In this regard, the present study is envisaged to assess the physical, rheological, and bread-making properties of teff flour acquired over roller, hammer, and pin milling. Among the milling methods, the distribution of particles was more uniform in case of roller mill, while finer particles were obtained for the pin milled flour fractions with 60% of the sample falling below 90 μm. It was observed that the protein, crude fiber, and crude fat contents for all the flours were on par with each other irrespective of the milling method. Whereas, the pasting properties varied significantly between the flours obtained from different milling methods. It was observed that the pin milled flour bread was superior in quality owing to its higher loaf volume (331.67 cm3 ) with lower hardness value (5.99 N). The present study indicates the fact that pin mill could be more suitable for milling brown teff grains owing to the better pasting and bread-making properties.

Evolutionary engineering to improve Wickerhamomyces subpelliculosus and Kazachstania gamospora for baking.

The conventional baker's yeast, Saccharomyces cerevisiae, is the indispensable baking yeast of all times. Its monopoly coupled to its major drawbacks, such as streamlined carbon substrate utilisation base and a poor ability to withstand a number of baking associated stresses, prompt the need to search for alternative yeasts to leaven bread in the era of increasingly complex consumer lifestyles. Our previous work identified the inefficient baking attributes of Wickerhamomyces subpelliculosus and Kazachstania gamospora as well as preliminarily observations of improving the fermentative capacity of these potential alternative baker's yeasts using evolutionary engineering. Here we report on the characterisation and improvement in baking traits in five out of six independently evolved lines incubated for longer time and passaged for at least 60 passages relative to their parental strains as well as the conventional baker's yeast. In addition, the evolved clones produced bread with a higher loaf volume when compared to bread baked with either the ancestral strain or the control conventional baker's yeast. Remarkably, our approach improved the yeasts' ability to withstand baking associated stresses, a key baking trait exhibited poorly in both the conventional baker's yeast and their ancestral strains. W. subpelliculosus evolved the best characteristics attractive for alternative baker's yeasts as compared to the evolved K. gamospora strains. These results demonstrate the robustness of evolutionary engineering in development of alternative baker's yeasts.

Native and fermented waxy cassava starch as a novel gluten-free and clean label ingredient for baking and expanded product development.

Amylose-free and wild-type cassava starches were fermented for up to 30 days and oven- or sun-dried. The specific volume (ν) after baking was measured in native and fermented starches. The average ν (across treatments) for waxy starch was 3.5 times higher than that in wild-type starches (17.6 vs. 4.8 cm3 g-1). The best wild-type starch (obtained after fermentation and sun-drying) had considerably poorer breadmaking potential than native waxy cassava (8.4 vs. 16.4 cm3 g-1, respectively). The best results were generally obtained through the synergistic combination of fermentation (for about 10-14 days) and sun-drying. Fermentation reduced viscosities and the weight average molar mass led to denser macromolecules and increased branching degree, which are linked to a high loaf volume. The absence of amylose, however, was shown to be a main determinant as well. Native waxy starch (neutral in taste, gluten-free, and considerably less expensive than the current alternatives to cassava) could become a new ingredient for the formulation of clean label-baked or fried expanded products.

Selectively hydrolyzed soy protein as an efficient quality improver for steamed bread and its influence on dough components

Selectively hydrolyzed soy protein (SHSP) has the potential to improve the quality of steamed bread. To clarify its underlying mechanism, the influence of SHSP on dough properties and components was investigated and compared with that of soy protein isolate (SPI). The results showed that SHSP addition resulted in steamed bread with higher loaf volume, lower hardness, and higher viscoelasticity. In contrast, SPI addition had the opposite effect. Nevertheless, both soy proteins decreased melting enthalpy and increased starch particle exposure due to competition for water. By analyzing molecular weight distribution and the secondary structure, we determined that the GMP content of fermented dough decreased by 10.04% following 1% SPI addition; however, it was enhanced by 7.90% following 1% SHSP addition. Moreover, the content of β-turns decreased with SHSP addition. The present study provides a theoretical basis for the exploitation of soy proteins as a nutritious and technofunctional dough improver.

Thin film drainage dynamics of wheat and rye dough liquors and oat batter liquor

To obtain bread with a high loaf volume and homogeneous crumb, gas cells require sufficient stability until the discontinuous gas structure of dough is transformed into the continuous structure of bread. At the end of fermentation, dough gas cells are supposedly regionally separated by two air-water (A-W) interfaces and a liquid film. ‘Dough liquor’ (DL) or ‘batter liquor’ (BL), i.e. the supernatant after ultracentrifugation of dough and batter, respectively, is a model system for the fluid in these films. We report here on drainage dynamics of free-standing thin films (TFs) prepared from wheat and rye DLs and oat BL after applying a driving pressure of either 50 or 200 Pa at bulk concentrations lower than and equal to (‘native’) those in the respective supernatants obtained by ultracentrifugation. At lowered bulk concentrations, wheat and rye DL TFs were surrounded by planar and dimpled A-W interfaces, respectively, both of which were composed of weakly viscoelastic mixed protein-lipid films. In contrast, lipids stabilized dimpled oat BL TFs by migrating along their A-W interfaces and thus by generating Marangoni stresses. Liquid drainage and subsequent film rupture occurred rapidly in these TFs. At native bulk concentrations, TFs generally drained much slower and they were even found to be stable at small thicknesses (<100 nm). Here, lipids stabilized dimpled wheat DL and oat BL TF A-W interfaces by Marangoni effects or by forming a densely-packed layer, respectively. In addition, wheat DL and oat BL TFs at their native concentrations exhibited stratification due to layered structuring of micelles, which contributed to TF stability by exerting oscillatory structural forces. Thus, it can here be concluded that wheat DL and oat BL constituents at their native concentrations may contribute substantially to stabilizing gas cells in dough.

Technological methods for reducing the content of fructan in rye bread

The irritable bowel syndrome (IBS) is a functional disorder of the gastrointestinal tract that may afflict even 12% of the European population. One of the ways to counteract IBS-related ailments is to implement a diet with reduced contents of fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). The prevailing components from the FODMAPs group that may be found in rye bread include fructans. The study was conducted with endosperm and wholemeal rye flours. Dough was prepared from both flours with the use of two methods: I-stage method—with the addition of dry leavening—and II-stage method with the use of a sourdough produced with Lactobacillus plantarum, and all with fermentation times of 90, 120, 150, and 180 min. After baking, bread loaves were subjected to quality and consumer analysis and fructan content determination. The endosperm rye flour used for bread-making revealed better baking properties. Bread made of this flour had a higher loaf volume and received higher scores in the consumer assessment than bread made with wholemeal. Study results conclude that the content of fructans in bread was significantly affected by the dough-making method, and that it was decreased by the use of the sourdough. In contrast, the extended fermentation time of dough failed to reduce the fructan content of the bread.

Elucidation of rheological properties and baking performance of frozen doughs under different thawing conditions

The effects of thawing methods (refrigerator, ambient, proofer, and microwave thawing) on the quality attributes of frozen doughs were investigated mainly in terms of dough rheology and baking performance. While the use of microwave shortened the thawing times, it caused the dough samples to have uneven temperature distribution, which was thermo-graphically confirmed. The highest weight loss was observed in the microwave-thawed samples, followed by ambient, refrigerator, and proofer thawed ones. The dough samples thawed in a proofer and microwave tended to have lower and higher resistance against mixing, respectively. The microwave-thawing produced doughs with higher storage and loss moduli that were related to a harder and more chewy texture. The dough thawed at refrigerated and ambient temperatures produced bread samples with higher loaf volume, showing a highly linear correlation with the number of viable yeast cells (R2 = 0.9957). The refrigerator and ambient thawing produced breads with a softer texture.

Crucial role of amylose in the rising of gluten- and additive-free rice bread

Gluten- and additive-free rice bread is suitable for consumption by individuals who are sensitive to gluten and prefer to avoid additives. Here, we prepared 100% rice bread, which is a gluten-free rice bread prepared in the absence of additives, using 19 rice flour samples containing amylose contents ranging from 9.6 to 22.3%. The amylose content was positively correlated with the specific volume of the 100% rice bread, whereas no correlation was observed between the protein content and the specific volume. The amylose content was also positively correlated with the specific volume of gluten-free rice bread prepared following protease treatment of the dough. The dough of 100% rice bread prepared from rice flour containing higher amylose contents was better stabilized during leavening than that prepared from rice flour containing a lower amylose content. It was therefore apparent that amylose plays an important role in the preparation of 100% rice bread with a high loaf volume through stabilization of the dough.

Effect of bran hydration with enzymes on functional properties of flour–bran blends

AbstractBackground and objectivesHard red wheat bran and hard white wheat bran were prehydrated and treated with cellulase, xylanase, or cellulase + xylanase to mitigate the adverse effects of bran on the bread‐baking quality of whole wheat meals.FindingsThe hydration of bran with cellulase increased its soluble sugar content and decreased its soluble and insoluble fiber contents. Bran hydration with cellulase + xylanase was more effective at increasing soluble sugar and lowering insoluble fiber, indicating more extensive degradation of cell wall materials. The compositional changes of bran induced by hydration with cellulase or cellulase + xylanase affected the starch pasting and dough mixing properties of the flour–bran blends, showing delayed/inhibited starch gelatinization and decreased water absorption during dough development. A higher loaf volume was observed in bread containing bran hydrated with a low dose of xylanase or cellulase + xylanase in hard red wheat and in bread containing bran hydrated with low‐dose xylanase in hard white wheat.ConclusionsThe prehydration of wheat bran with enzymes could effectively improve the baking quality of whole wheat meals prepared from flour–bran blends by inducing changes in the composition of bran and subsequently in the physicochemical properties of starch and gluten.Significance and noveltyThe prehydration of wheat bran with enzymes can be an effective approach for enhancing whole wheat bread processing.

A comparative study of gluten-free sprouts in the gluten-free bread-making process

The addition of sprouted grains and seeds to cereal products has been identified as one of the upcoming trends in recent market reports. In this study, seven types of sprouts (amaranth, brown millet, corn, lentil, lupin, pea, quinoa) were milled and characterised with respect to their compositional (starch, protein, fat, ash, fibre, moisture) and functional properties (water hydration properties). These sprouted flours were included in a gluten-free bread formulation at a level of 5% and the impact on dough (temperature-dependent rising behaviour, pasting and rheological properties) and bread quality parameters (volume, crumb structure and texture) was evaluated. Factors such as the method of germination and the botanical origin influenced the chemical composition of the applied raw material. The functional properties of the different malts and sprouts are affected by the chemical composition of the individual grains. The differences in functional properties were, in turn, found to affect the dough properties and the quality parameters of the baked gluten-free breads. However, statistical analysis showed no correlation between the various factors. Based on this, effects on dough and bread properties were hypothesised to be caused by a combination of multiple factors. All bread formulations containing sprouted flour had significantly improved bread quality parameters in comparison to the control (without sprouted flour). The addition of amaranth sprouted flour, however, resulted in the highest loaf volume and the softest breadcrumb, suggesting its potential for further investigations in further studies.

Effect of lavender (Lavandula angustifolia) and melissa (Melissa Officinalis) waste on quality and shelf life of bread

The effect of lavender (Lavandula angustifolia) and melissa (Melissa Officinalis) waste on preparation, characteristics and shelf life of bread was investigated. It was found that lavender and melissa waste, generated yearly in large amounts, were rich on polyphenols (especially rosmarinic acid) and aroma compounds, and exhibited high antioxidant and antimicrobial activity. The bread with 2.5% lavender waste was characterized with the highest loaf volume and loaf specific volume. The total dietary fiber increased three times and the polyphenols and flavonoids increased more than four times for breads with added 5% lavender and melissa waste, compared to control sample. The breads with 2.5% and 5% added lavender waste had increased shelf life (up to 96 h) compared to control, and no fungal or bacterial spoilage was observed during storage at 22 °C, 30 °C and 37 °C for four days. The sensory evaluation demonstrated that the consumers preferred mainly bread with 2.5% lavender waste.

POTENSI EDAMAME SEBAGAI PENGGANTI KUNING TELUR DALAM PEMBUATAN DONAT MENGANDUNG KENTANG

Addition of potato in doughnut will decrease the loaf volume, thus it requires the addition of egg yolk egg as emulsifiers to improve the loaf volume of the doughnut. Egg yolk is known to contain high cholesterol, therefore in this study edamame (Glycine max L. Merill) slurry is used as an egg yolk replacer. Five different proportions of edamame slurry were added to doughnut dough and their influence on the specific volume, porosity, water content, oil absorption, texture of hardness, cohesiveness and springiness were observed. The optimum variable was determined based on highest loaf volume using Response Surface Method (RSM). Factor used for the RSM was the slurry proportion to achieve 7 levels which were then verified. The optimum treatment was the addition of 18.14% of edamame slurry with resulted in 117.53% of loaf volume, 2.92 N of hardness level, 0.83 of cohesiveness level, 4.45 of springiness level, 30.66% of water content, 7.68% of protein, 17.87% of fat, 8.04% of crude fiber, 0.74% of ashes, 43.06% of carbohydrate, and 16.55% of total sugar.

Whole Grain Wheat Flour Production Using an Ultracentrifugal Mill

Interest has been growing in whole grain products. However, information regarding the influence of the ultracentrifugal mill on whole grain flour quality has been limited. An experiment was conducted to produce whole wheat flour with hard red spring (HRS) wheat using an ultracentrifugal mill. This study determined the effect of centrifugal mill parameters as well as grain moisture (10–16%) on producing whole wheat flour and its final products. Mill parameters studied were rotor speed (6,000–15,000 rpm) and feed rate (12.5–44.5 g/min). Results showed that fine particle size (&lt;150 µm) was favored by low seed moisture content (10–12%) and high rotor speed (12,000–15,000 rpm). Flour moisture content was positively related to seed moisture content. Wheat grain with low seed moisture content (10–12%) milled with high rotor speeds (12,000–15,000 rpm) produced desirable whole grain wheat flour quality, with 70–90% of fine particle size portion and low damaged starch (less than 11%). This whole wheat flour produced uniform and machinable dough that had low stickiness and formed bread with high loaf volume.