Improvers and functional ingredients in whole wheat bread: A review of their effects on dough properties and bread quality

Improvement of whole wheat dough and bread properties by emulsifiers

The objective of this research was to determine effects of five enzymes on whole wheat bread properties, particularly loaf volume, bread texture, and staling. Enzymes containing conventional α-amylase (α-amyl), cellulase (cel), glucose oxidase, maltogenic α-amylase (m amyl), and xylanase (xyl) were added at three levels. Vital wheat gluten (VWG) was added as an additional, separate treatment at 2.5% (flour weight basis). Enzymes had minimal effect on water absorption and mixing time. Each enzyme increased specific loaf volume for at least one of the usage levels tested (P <0.01). Among the enzyme treatments, the greatest loaf volume was seen for xyl at the medium and high levels. No enzyme was as effective as VWG at increasing loaf volume. Overall, enzymes did not significantly change cell structure. The greatest reduction in fresh bread hardness was obtained for the high level of xyl. VWG, m amyl, and xyl reduced the rate of bread firming over 7 days. α-Amyl, cel, and m amyl decreased starch retrogradation at day 7 as measured by differential scanning calorimetry (P <0.01). M amyl nearly eliminated the endothermic peak for recrystallized amylopectin. This study demonstrated the specific application of enzymes in whole wheat bread to increase loaf volume and decrease initial crumb hardness and bread staling. PRACTICAL APPLICATION: This study will provide guidance for practical uses of enzymes in improving whole wheat dough and bread quality.

Proper gas cell stability during fermentation and baking is essential to obtain high-quality bread. Gas cells in wheat dough are stabilized by the gluten network formed during kneading and, from the moment this network locally ruptures, by liquid films containing nonstarch polysaccharides (NSPs) and surface-active proteins and lipids. Dough liquor (DL), the supernatant after ultracentrifugation of dough, is a model system for these liquid films and has been extensively studied mostly in the context of wheat bread making. Nonwheat breads are often of lower quality (loaf volume and crumb structure) than wheat breads because their doughs/batters lack a viscoelastic wheat gluten network. Therefore, gas cell stabilization by liquid film constituents may be more important in nonwheat than in wheat bread making. This manuscript aims to review the knowledge on DL/batter liquor (BL) and its relevance for studying gas cell stabilization in wheat and nonwheat (rye and oat) bread making. To this end, the unit operations in wheat, rye, and oat bread making are described with emphasis on gas incorporation and gas cell (de)stabilization. A discussion of the knowledge on the recoveries and chemical structures of proteins, lipids, and NSPs in DLs/BLs is provided and key findings of studies dealing with foaming and air-water interfacial properties of DL/BL are discussed. Next, the extent to which DL/BL functionality can be related to bread properties is addressed. Finally, the extent to which DL/BL is a representative model system for the aqueous phase of dough/batter is discussed and related to knowledge gaps and further research opportunities.

Dried and crushed dandelion roots (Taraxacum officinale F. H. Wigg.) (TO) were used as a formulation additive (at the amount of 0, 1, 3, 4, 5, and 6 g 100 g−1 flour) to wheat bread. The farinographic properties of the dough and the physical and chemical properties of the bread were evaluated. It was found that the addition of dried flour caused a significant decrease in water absorption by the flour (1% and higher TO level), an increase in the development time (from 2% to 5% TO addition) and dough stability (3% and 4% TO level), and an increase in dough softening (4% and higher TO level). As the substitution of TO for wheat flour increased, there was a gradual decrease in loaf volume, an increase in specific weight and crumb hardness, and a darkening of the crumb color. The total polyphenol content increased linearly with the percentage increase of dried root additions TO from 0.290 to 0.394 mg GAE g−1 d.m., which translated into an increase in the antioxidant activity of the bread. It was found that dried crushed roots of Taraxacum officinale can be a recipe additive for wheat bread; however, due to their specific smell and bitter aftertaste, the level of this additive should not exceed 3 g 100 g−1 flour.

Background and objectivesThis study aimed to determine the effect of xanthan gum on whole wheat dough and bread, especially dough rheological properties, gluten structures, loaf volume, and bread texture and staling.FindingsXanthan gum increased the water absorption and mixing time for whole wheat dough as determined by mixograph. Xanthan gum altered dough rheology as evaluated through the Kieffer extensibility test, Chen–Hoseney stickiness test, and compression test employed for extensional viscosity calculation. Gluten secondary structure was analyzed by FTIR spectroscopy. Changes to glutenin and gliadin extractability were measured by RP‐HPLC. Specific loaf volume increased from 3.74 to 4.38 cm3/g. Crumb hardness of fresh bread decreased more than twofold by xanthan inclusion. Hardness after 48 hr of bread storage was also lower than the control, but the rate of hardness increase was not reduced. Moisture loss over 48 hr decreased for 0.6% and 1.0% xanthan gum. DSC revealed that xanthan gum decreased amylose–lipid complexation, but did not affect amylopectin retrogradation.ConclusionsXanthan gum altered the rheological properties of whole wheat dough, increased whole wheat bread volume, and decreased the hardness of both fresh and stored bread. Future research could examine the effect of xanthan gum in combination with other crumb softeners and antistaling agents, in order to achieve both an increase in loaf volume and a decrease in staling for whole wheat bread.Significance and noveltyThis study may help improve the sensory appeal of whole wheat bread and ultimately increase whole grain consumption.

This study investigates the exploitation of buckwheat sourdough for the production of wheat bread. The fermentation induced extensive hydrolysis of buck- wheat main storage proteins, but did not influence the total protein, starch and polyphenols content of buckwheat. Buckwheat sourdough was incorporated at 10 and 20 % (w/w) in wheat dough, and control doughs were produced with the addition of a chemically acidified (CA) buckwheat batter. The addition of buckwheat sourdough greatly affected the rheological properties of the dough, by inducing a strengthening of the gluten network and decrease in elasticity. The acidification of wheat dough also stimulated the baker's yeast activity during proofing, resulting in higher release of CO2 in shorter times (volume of CO2 released (ml), control dough, 1,671.5; dough with 10 % sourdough, 2,600; dough with 10 % chemically acidified dough, 2,715.5). The properties of wheat bread were enhanced by the addition of 10 % buckwheat sour- dough, which led to higher specific volume (control, 3.41 ml/g; bread with 10 % sourdough, 4.03 ml/g) and softer crumb (crumb hardness, control, 5.28 N; bread with 10 % sourdough, 3.93 N). On the other hand, the higher acidification level did not influence the bread volume, but slightly hardened the crumb (crumb hardness, bread with 20 % sourdough, 7.41 N; bread with 20 % chemically acidified dough, 6.48 N). The fermentation positively influenced the nutritional properties of buckwheat flour and wheat bread, in terms of polyphenols (control bread, 8.84 mg GAE/100 g; bread with 10 and 20 % sourdough, 17.83 and 18.20 mg GAE/100 g, respectively) and phytic acid contents. Incorporation of buckwheat sourdough also led to an extension in the shelf life of wheat bread, which became more evident for the higher addition level. Overall, the results of this study suggest that buckwheat sourdough represents a suitable tool for enhancing the overall quality and nutritional properties of wheat bread.

Introduction. The aim of the present study was to investigate the effect of rosehip flour on some properties of wheat dough and bread. Materials and methods. Bread was prepared from wheat flour with the addition of rosehip flour in the amount of 5, 10 and 15% to replace the equal amount of the wheat flour. The used methods are standardized and generally accepted for evaluation of bread. Results and discussion. It was found that the addition of different amounts of rosehip flour to wheat flour affected the intensity of gas formation, as the percentage of rosehip flour added had increased, the intensity of gas formation decreased. When adding 5% rosehip flour, there was no significant deterioration of gas formation. Incorporation of rosehip flour into wheat dough resulted in a decrease in water absorption and degree of softening and the lowest results were found in the sample with 15% rosehip flour added. In terms of dough development time and consistency, there were no significant differences between the samples. Dough stability was found to be higher in the samples containing rosehip flour, with the highest value reported for the sample with 5% rosehip flour. Dough and bread color characteristics decreased with increasing the rosehip flour quantity. Darker colour of rosehip flour enriched samples could be due to the original colour of rosehip fibre, which is rather brown and slightly reddish. The substitution of wheat flour with rosehip flour resulted in a decrease in volume, specific volume, height/diameter ratio and baking loss of the wheat bread. Some of the sensory parameters of bread (crust color, aroma and taste) in the rosehip flour supplemented samples were rated higher by the panelists compared to the control sample, regardless of the amount of rosehip flour added. Conclusions. The rosehip flour could be successfully used as an additive in wheat bread formulation. In the sensory assessment bread samples with rosehip flour in terms of some properties such as crust color, aroma and taste had higher scores than the control sample.

Wheat flour, bread, and bakery products are an important source of macronutrients, micronutrients, dietary fibers, and antioxidants. Considering that Iran’s bread industry is the second highest bread-consuming industry in the world, this research is focused on the main operations of the bread production chain (wheat cultivation, milling, dough processing, and bread production). Investigating the sustainability and improvement strategies and farm-to-fork approach for the wheat-bread production chain was the aim of this work. Exergy analysis is a powerful tool in designing, optimizing, and evaluating the performance of energy systems to determine energy quality, compare different energy sources, and achieve maximum system performance. In this research, the cumulative degree of perfection, renewability index, and sustainability index of Iranian traditional loaves of bread (Sangak, Lavash, Barbari) and Baguette bread as a semi-industrial bread were estimated. Considering the functional unit of the weight of the produced bread, Baguette and Sangak breads had the highest and lowest sustainability, respectively. Considering the functional unit of energy of the produced bread, Baguette bread has the lowest exergy consumption per 100 cal of the embedded energy of bread. According to the obtained results, the bakery consumes the most exergy in the wheat-bread chain. Natural gas input is the most important indicator of unsustainability in bakeries. Meanwhile, in the entire wheat-bread chain, human labor and natural gas consumption were factors of unsustainability. By using renewable sources, the renewable index increased by 76–89%. Additionally, the use of renewable resources increased the sustainability index of bread production by 7.6 to 1.9 times.

The effect of flour extraction rate and baking on thiamine (vitamin B1) and riboflavin (vitamin B2) content and antioxidant capacity of traditional ginger cake was studied and then compared to white wheat bread. Ginger cake was formulated either with whole-grain (100% extraction rate) or with brown (92% extraction rate) rye flour and baked at 180 °C for 18 min. The antioxidant capacity was evaluated in terms of radical scavenging activity against peroxyl (ROO·) and superoxide anion radicals (O2·−). Thiamine content in rye doughs (F-100% and F-92%) was found to be 38% lower when compared to wheat dough. In contrast, whole-grain and brown rye doughs exhibited an almost fourfold higher riboflavin content than wheat dough. Rye dough baking led to reductions in thiamine (from 53 to 65%) and riboflavin (from 69 to 71%) contents. Likewise, thiamine and riboflavin contents in wheat dough were also reduced (56 and 10%, respectively) after baking; however, ginger cake with whole-grain rye flour exhibited significantly higher thiamine and riboflavin contents. Rye doughs and ginger cakes showed higher scavenging activities against ROO· radicals when compared to that of wheat dough and bread. Thus, baking significantly enhanced ROO· scavenging properties of ginger cakes while only a slight increase was observed in wheat bread. In contrary, baking gave rise to a decrease in SOD-like activity both in ginger cake or wheat bread. Our findings suggest that formulation with whole-grain rye flour can potentially increase B1 and B2 vitamin contents as well as the ROO· scavenging capacity of traditional ginger cake.

Background and objectivesTea fiber is a co‐product of black tea production. It is a cheap and good source of fiber and polyphenols. In this study, the impact of finely ground tea fiber addition (2.5, 5.0, 7.5, and 10.0%) on wheat dough and bread was evaluated.FindingsTea fiber contained 8.39% moisture, 15.65% protein, 1.58% fat, 3.63% ash, 17,289 mg GAE/kg tea fiber phenolic, and 67.62% total dietary fiber. The addition of tea fiber (2.5%, 5.0%, 7.5%, and 10.0%) decreased dough stability and extensibility, index of swelling, baking strength, loaf volume, and specific volume while increased dough development time, water absorption, dough tenacity, configuration ratio, the degree of dough softening and firmness. The baking loss of bread made with tea fibers and control were not significantly different. Crumb characteristics were similar to control loaf, except bread with 10.0% tea fiber added. The control, bread with 2.5% and 5.0% had the same sensory parameters.ConclusionIn bread making, 2.5% of tea fiber can be recommended as a fiber‐enriching agent.Significance and noveltyThis paper shows the characterization of tea fiber and its effect on wheat flour and dough.

Cyclodextrins (CDs) are cyclic oligosaccharides that have found widespread application in numerous fields. CDs have revealed a number of various health benefits, making them potentially useful food supplements and nutraceuticals. In this study, the impact of α-, β-, and γ-CD at different concentrations (up to 8% of the flour weight) on the wheat dough and bread properties were investigated. The impact on dough properties was assessed by alveograph analysis, and it was found that especially β-CD affected the viscoelastic properties. This behavior correlates well with a direct interaction of the CDs with the proteins of the gluten network. The impact on bread volume and bread staling was also assessed. The bread volume was in general not significantly affected by the addition of up to 4% CD, except for 4% α-CD, which slightly increased the bread volume. Larger concentrations of CDs lead to decreasing bread volumes. Bread staling was investigated by texture analysis and low field nuclear magnetic resonance spectroscopy (LF-NMR) measurements, and no effect of the addition of CDs on the staling was observed. Up to 4% CD can, therefore, be added to wheat bread with only minor effects on the dough and bread properties.

Influence of dextran-producing Weissella cibaria on baking properties and sensory profile of gluten-free and wheat breads

Regulation of baking quality and starch digestibility in whole wheat bread based on β-glucans and protein addition strategy: Significance of protein-starch-water interaction in dough

Effect of different molecular weight β-glucan hydrated with highland barley protein on the quality and in vitro starch digestibility of whole wheat bread

Compared to refined wheat flour, whole wheat flour contains higher nutrients, but its high content of dietary fiber can have a significant impact on the quality of the final product. Therefore, how to enable consumers to obtain health benefits from whole wheat flour and improve the processing performance of whole wheat products has become a concern. The purpose of this study is to apply 2 strains Bacillus sp. SH and Aspergillus oryzae Y21 with cellulase production capacity and study their adaptability in whole wheat dough. The results indicate that the addition of cellulase-producing strains enhanced the acid production ability of whole wheat dough, rapidly reduced its pH value and insoluble dietary fiber content, and significantly increased the water-soluble arabinoxylan and water-soluble dietary fiber content. During the fermentation process, the viscoelasticity of the dough decreased, free sulfhydryl content increased, wet gluten content decreased, and the degree of reduction was consistent with the degree of acidification. Moreover, the proteolytic activity of the dough was increased, and the hydrolysis of gliadin was the most extensive. SH showed a higher advantage and has been used in whole wheat bread making. Increasing the proportion of strain SH in whole wheat bread can improve the structural characteristics and texture of the bread. When SH (5 × 107 CFU/g) is added to whole wheat bread, its hardness, elasticity, chewiness, and resilience can be similar to those of bread made from control group wheat flour, far exceeding that of whole wheat bread without adding SH. The addition of cellulase producing strains has obvious advantages in the development of whole-wheat dough, and also promote the development of whole wheat fermented foods as staple foods.