Rheological properties of wheat flour and quality characteristics of pan bread as modified by partial additions of wheat bran or whole grain wheat flour

The use of bran and whole grain flour changes dough rheology and causes difficulties in manufacturing bakery products. The aim of this study was to analyse the influence of substituting refined wheat flour (WF) by wheat bran (WB; 5%, 10%, 20%, 30% and 40%) or whole grain wheat flour (WGWF; 10%, 20%, 30%, 40% and 50%) on dough rheological properties and pan bread quality characteristics. The addition of WB and WGWF increased water absorption and resistance to extension and decreased stability, extensibility and peak viscosity. Effects with WB were more pronounced. The presence of WB or WGWF increased crumb moisture content, firmness and hardness and decreased specific volume of pan bread. It is important to set new farinographic and extensographic standards when using WB and WGWF, allowing for a correct correlation between rheology and quality characteristics of bakery products, as the same standards used for WF are not valid.     

Sunflower protein concentrate: A possible and beneficial ingredient for gluten-free bread

The global demand for gluten-free products increased and resulted in a significant technological challenge for the bakery industries: producing gluten-free bread with similar quality to wheat bread. This study aimed to analyze the effects of different concentrations of sunflower protein concentrate (SPC) addition on the gluten-free bread quality parameters compared to the use of pea flour. The SPC flour was inserted at 5%, 10%, and 20% on a flour basis mixture (70% rice flour and 30% cornstarch). Some parameters as specific volume, color, and texture profile were evaluated during 21 days of storage. The obtained results showed that SPC has a significant potential to be used in gluten-free bread with high quality and sensory acceptability. The addition of this beneficial ingredient, in all concentrations, resulted in gluten-free bread with lower hardness after 21 days of storage and with a 100% increment in the protein content when compared to pea flour bread.     

Okara flours from chickpea and soy are thickeners: increased dough viscosity and moisture content in gluten-free bread

The by-product of plant-based beverages, okara, can be dried in a nutritious flour, but it generates dense bakery products due to high water absorption. Gluten-free bread often tastes dry, so the objective of this work was evaluating okara flour as thickener for mouthfeel enhancement. Proximate analysis revealed that chickpea okara contained more starch than soy (35.3 vs. 3.41 g/100 g), less insoluble fibre (43.3 vs. 57.0 g/100 g) and protein (9.51 vs. 18.1 g/100 g). Water absorption capacity was higher in okara than flour and for soy (8.29 vs. 6.01 g g⁻¹, respectively). When added to a gluten-free batter, both okara flours significantly increased viscosity. Upon addition of either okara to gluten-free bread (2% w/w) moisture content increased from 31.6 to 33.5 and 36.5 g/100 g, while crumb hardness increased by up to 45% and specific loaf volume decreased by up to 42%. Soy okara flour enhanced moistness of gluten-free bread.     

New opportunities for gluten-free diet:teff (Eragrostis tef) as fibre source in baking products

This study assessed physicochemical parameters of high fibre and gluten-free breads made with teff and associated flours. Four breads samples were developed: wheat flour (T1), teff flour (T2), teff flour + cassava starch + rice flour (T3 and T4). Hedonic evaluation of sensory attributes characterising the samples was performed by coeliac and non-coeliac subjects. Breads made with different percentages of teff flour showed huge amount of total and insoluble fibres. The wheat bread presented the highest values for pH and the texture parameters analysed, except for crumb hardness and elasticity. The sensory analysis showed that all samples made with teff were well accepted by coeliac and non-coeliac subjects. Purchase intention and the acceptability index suggested a potential market success for the developed products. Teff flour showed promising use for its technological and nutritional values as well as sensory properties, supporting the hypothesis that it is possible to develop new gluten-free bakery products without decreasing consumers’ satisfaction.     

Effect of dietary fibre enrichment on selected properties of gluten-free bread

The enrichment of gluten-free baked products with dietary fibre seems to be necessary since it has been reported that coeliac patients have generally a low intake of fibre due to their gluten-free diet. In the present study different cereal fibres (wheat, maize, oat and barley) were added at 3, 6 and 9 g/100 g level into a gluten-free bread formulation based on corn starch, rice flour and hydroxypropyl methyl cellulose (HPMC). Doughs were evaluated based on consistency, viscosity and thermal properties. Results showed that maize and oat fibre can be added to gluten-free bread with positive impact on bread nutritional and sensory properties. All breads with 9 g/100 g fibre increased the fibre content of control by 218%, but they were rated lower than those with 3 and 6 g/100 g fibre due to their powdery taste. The formulation containing barley fibre produced loaves that had more intense color and volume comparable to the control. During storage of breads a reduction in crumb moisture content and an increase in firmness were observed. The micrographs of the crumb showed the continuous matrix between starch and maize and/or oat fibre obtaining a more aerated structure.     

Effect of Microwave Radiation Pretreatment of Rice Flour on Gluten-Free Breadmaking and Molecular Size of β-Glucans in the Fortified Breads

Cereal β-glucan concentrates can be used in gluten-free breads to improve dough handling properties and quality of final products as well as to enhance their nutritional value; however, the presence of endogenous β-glucanases in rice flour, in combination with prolonged mixing, fermentation, and proofing time, can cause a substantial reduction in β-glucan molecular weight, affecting detrimentally their efficacy for bioactivity. In this study, microwave (MIWA) heating was applied to the rice flours before breadmaking at different flour water contents (13–25%) and treatment times (0-4 min) to reduce β-glucanase activity. Gluten-free breads made from the MIWA-treated rice flours were fortified with oat β-glucan concentrate to enhance their nutritional profile. The molecular weight of added β-glucan in the final products increased with increasing both flour water content and time of MIWA treatment, reflecting the magnitude of residual β-glucanase activity in the flour. Pretreatment with MIWA radiation for 4 min of the rice flour tempered at 25% moisture resulted in negligible residual β-glucanase activity and preserved to a great extent the molecular weight of β-glucans in the enriched breads. End-product quality was not affected by flour MIWA pretreatment, and even a slightly higher loaf specific volume was noted for breads made from the MIWA-treated flours (4 min MIWA at 25% moisture content) compared to that of untreated flour. These findings can contribute to the improvement of nutritional value of rice-based gluten-free breads for celiac consumers as well as of any β-glucan-containing yeast-leavened bakery product without altering its sensorial attributes. Additional studies are still required for further evaluation of the effect of more intense microwave treatment on rice flour and its application on breadmaking.     

Gluten-free pasta production from banana and cassava flours with egg white protein and soy protein addition

Egg white protein and soy protein were incorporated into a banana and cassava flour blend (75:25) to produce gluten-free pasta. The objectives of study were to investigate the effects of the different protein sources on the physico-chemical properties of gluten-free pasta. The levels of protein inclusion were 0%, 5%, 10% and 15% of composite flour (w/w) for each type of protein. Pasta made from 100% durum wheat semolina was used as controls. The protein fortification affected the total starch, resistant starch and protein content of gluten-free pasta compared to semolina pasta. No significant effects of soy/egg white protein addition were found in either insoluble or soluble dietary fibre content. Cooking properties of pasta (optimum cooking time, swelling index, water adsorption index and cooking loss) and texture properties (firmness and extensibility) were affected by the level of protein addition and the type of protein. Results showed the utilisation of 25% cassava flour and protein inclusion have a promising application in gluten-free pasta production.     

The advantage of using extrusion processing for increasing dietary fibre level in gluten-free products

Gluten-free products generally are not enriched/fortified and frequently are made from refined flour and/or starch. Such products have been found to provide lower amounts of total dietary fibre than their enriched/fortified gluten-containing counterparts.The objective of this study was to increase the level of total dietary fibre in gluten-free products by using extrusion technology and by incorporating a number of different fruits and vegetables, such as apple, beetroot, carrot, cranberry and gluten-free Teff flour cereal. The materials were added at the level of 30% into the gluten-free balanced formulation (control) made from rice flour, potato starch, corn starch, milk powder and soya flour. Different process conditions, such as water feed rate 12%, solid feed rate 15–25 kg/h, screw speed 200–350 rpm, barrel temperatures: 80 °C at feed entry and 80–150 °C at die exit were used. Pressure, material temperature and torque were monitored during extrusion runs. The relationships and interactions between raw ingredients, extrusion processing parameters and resulting extrudate nutritional and textural properties were investigated.The results of this study clearly show that extrusion technology has the potential to increase the levels of total dietary fibre in gluten-free products made from vegetables, fruits and gluten-free cereals.     

Extrusion of Soybean and Wheat Flour as Affected by Moisture Content

The effect of moisture content (MC) on texture and properties of extrudates with varied ratios of soybean flour (SF) and wheat flour (WF) was studied. A single-screw extruder was used at screw speed 200 rpm. MCs of blends were 16, 17 or 18%, w.b. The properties of extrudates depended on flow rate of the material during extrusion. The flow rate revealed a nonlinear dependence on the blend composition and the MC at the same volume of filling of the screw feeding section. The expansion ratio of WF or SF extrudates increased with lowering of the MC. Unexpectedly, the expansion ratio decreased with lower MC for the composite extrudates. Optimal extrudate properties at 16% (w.b.) MC corresponded to 80, 90 or 100% (d.b.) WF and 20, 10% or no SF, respectively. At 17 and 18% MC, optimal properties were found for products containing 80 or 90% WF and 20 or 10% SF, respectively.     

The role of corn starch,amaranth flour,pea isolate,and Psyllium flour on the rheological properties and the ultrastructure of gluten-free doughs

The removal of gluten from bakery products, in order to produce foods (mainly based on gluten-free cereal flours and starch) for people with celiac disease, impairs dough’s capacity to properly develop during leavening and baking. The main aim of this research was to produce and evaluate some experimental gluten-free (GF) doughs containing different levels of corn starch, amaranth flour (to enhance the nutritional benefits), pea isolate (to increase the protein content) and Psyllium fiber (as thickening agent and fiber source) in order to study the influence of the different ingredients on the rheological properties and on the ultrastructure of the doughs. Psyllium fiber generally enhanced the physical properties of the doughs, due to the film-like structure that it was able to form, and the most complex among the experimental formulations looked promising in terms of final bread technological and nutritional quality even when compared to two different commercial GF mixtures.     

Chemical, nutritional and sensory properties of bread supplemented with lupin seed (Lupinus albus) products

Sweet lupin Lupinus albus seed flour (SLSF), two sweet lupin protein isolates (SLPI-I and SLPI-II) and sweet lupin seed protein concentrate (SLSPC) were added to wheat flour (WF) in an amount of 3, 6, 9 and 12% of wheat flour. The effects of lupin products supplementation on physical dough properties were studied using a Brabender farinograph. Loaves were prepared from the various blends using the straight dough procedure and then evaluated for volume, crust and crumb colour, crumb texture, flavour and overall quality. Water absorption, development time and dough weakening were significantly (P < 0.05) increased as the lupin product levels increased in all doughs; however, dough stability decreased. Lupin products could be added to WF up to 9% level (SLPI-I and SLPI-II) and 6% level (for other lupin products), without any observed detrimental effect on bread sensory properties. No significant (P > 0.05) differences were recorded in loaf volume between control and breads containing SLPI-I and II (up to 9% level) and SLSPC (up to 3% level). Addition of lupin products increased the content of protein and total essential amino acids, especially lysine. The addition also improved in-vitro protein digestibility.     

Possibilities to increase the quality in gluten-free bread production: an overview

The market for gluten-free products is increasing. Owing to better diagnostic methods, more and more people are identified to have coeliac diseases. Production of bakery products that do not harm these people is a big challenge for bakers and cereal scientists in the twenty-first century. The use of different cereals and flours makes it necessary to find possibilities to take over the task of gluten by other flour ingredients, by the addition of different components, by different flour and dough treatment or by changing the method of baking. The purpose of this review is to give an overview about the various possibilities to increase the baking quality of gluten-free bakery products, increasing their water-binding capacity, uniform the crumb structure and increase the final bread volume. All the listed methods and ingredients are already in single use helpful to increase the quality in gluten-free bread production.     

Nutritional,physicochemical, and textural properties of gluten-free extruded snacks containing cowpea and whey protein concentrate

Ready-to-eat extruded snacks with high protein and fibre were developed from a composite flour comprising rice flour, cowpea flour and whey protein concentrate (WPC). Nutritional, physicochemical, and textural properties of extrudates were evaluated, at five ratios of cowpea: WPC (10:0, 15:05, 20:10, 25:15, 30:20); rice flour was used as a control. The protein and fibre content in the extrudates significantly increased (P ≤ 0.05) with cowpea (10%–30%) and WPC (5%–20%) incorporation compared to the control. The extrudates with higher levels of cowpea and WPC showed a significant increase in bulk density and hardness. A slight decrease of 12% was observed in the expansion of 15% cowpea and 5% WPC fortified extrudates compared to the control. The number of peaks during compression increased with incorporations of cowpea and WPC. All cowpea and WPC containing snacks were darker than the control. Significant correlations were found between the protein, fibre, colour values and textural properties. The essential and non-essential amino acid profiles increased in the extrudates, proportionally to the cowpea and WPC fortification.     

Utilisation of pigeon pea (Cajanus cajan L) byproducts in biscuit manufacture

Biscuits were prepared by substituting wheat flour with dehulled pigeon pea (Cajanus cajan L) flour (PPDF) or pigeon pea byproduct flour (PPBF). PPBF was obtained by recovering edible cotyledon material from milling byproducts. PPBF had a higher level of protein (29.42 g/100g) compared to PPDF (24.67 g/100g). Composite flour blends were prepared by substituting wheat flour (WF) with either PPDF or PPBF at 95:5, 90:10, 85:15, 80:20 and 75:25 incorporation levels. Biscuits were analysed for composition, physical and sensory parameters. Protein content of PPDF and PPBF fortified biscuits increased by 1.3 and 1.4 times respectively compared to control along with a significant increased in fibre content. Results indicate that good quality biscuits with increased levels of protein and fibre can be prepared by substituting wheat flour using 85:15 of PPDF or 90:10 of PPBF without significantly affecting the sensory quality of biscuits. This study demonstrates the potential feasibility of incorporating pigeon pea milling byproducts in the manufacture of biscuits.     

Enrichment of Egyptian 'Balady' bread. Part 1. Baking studies, physical and sensory evaluation of enrichment with decorticated cracked broadbeans flour (Vicia faba L.)

Physical, rheological and baking properties of decorticated cracked broadbeans-wheat composite flours were studied and the acceptability of the Egyptian 'Balady' bread was evaluated by sensory tests. Decorticated cracked broadbeans flour (DCBF) was used to replace 5%, 10%, 15% and 20% of the wheat flour (WF) in bread. Farinographic studies showed that water absorption, arrival time and dough development time increased as the amount of DCBF increased, while dough stability time increased at 5% and 10% of DCBF substitution and decreased at 15% and 20% substitution. Also, the extensographic energy of the dough decreased as DCBF substitution increased, while the ratio between resistence and extensibility increased. There was a decrease in peak viscosity with increased amounts of DCBF. A reduction of the diameter and weight of bread loaf was observed as the amount of DCBF increased. The sensory properties of 'Balady' bread showed that at the two levels of 5% and 10% DCBF-substitution, the 'Balady' loaves did not show any significant differences (P > 0.05). It is concluded that the replacement of bread flour (WF) with up to 10% decorticated cracked broadbeans flour produced acceptable Egyptian 'Balady' bread.     

The effect of fermentation temperature, flour type, and starter on the properties of sour wheat bread

The effects of the type of wheat flour (white or dark), fermentation temperature (25°C or 30°C) and origin of starter (bakery A compared with bakery B) on acid production and bread properties were examined in a factorial design. The type of flour was the most important factor; with dark flour (ash content 1.64%) the acetic acid concentration in the bread was almost double that from white flour (ash content 0.86%); lactic acid was 30 to 50% higher. Acid production increased as fermentation temperature increased to 30°C, but was not influenced by the origin of the starter.
Loaf specific volume decreased with acid concentrations, but souring lengthened the mould-free time from 4 days to 5 to 8 days or more as acidity increased. Sour wheat bread had a characteristic taste. Those with higher acidity values were more bitter and pungent.
Rye sour and rye sour bread production technology could also be utilized in white bread making.     

添加玉米醇溶蛋白对荞麦面团特性的影响

为探究玉米醇溶蛋白（Zein）对荞麦无麸质面团流变学特性的影响,将气流膨化苦荞粉与甜荞粉以1:1混合制得基料粉（以下称混粉）。用90%乙醇溶液对Zein进行增塑处理,然后按照0%、5%、10%、15%、20%的添加量（以混粉计）与混粉及水揉混制得荞麦无麸质面团（以下称面团）,并对面团静态流变学特性（质构特性、拉伸特性和应力松弛特性）、动态流变学特性、光学性质（色度和反光率）以及微观结构等进行测定。结果表明,随着Zein添加量从0%增加到20%,面团的硬度从482.38 g降低到346.60 g,弹性从0.21升高到0.29,拉伸距离从15.44 mm升高到38.16 mm,抗拉伸力从13.10 g升高到72.04 g。面团的残余应力、黏弹系数和松弛时间相对于对照组显著升高（P<0.05）,但随着Zein添加量的增加均逐渐减小,面团G’和tanδ值、面团表面亮度及反光率均得到明显改善,微观结构相比对照组能够明显地观察到蛋白纤维丝。以上结果充分表明,Zein可有效地改善荞麦无麸质面团结合力和延伸性差的缺陷。本研究为无麸质食品结构及加工特性改善提供了一个新的途径。     

Insects as ingredients for bakery goods. A comparison study of H. illucens,A. domestica and T. molitor flours

Due to a rising demand for proteins, food industry is considering new alternative protein sources that can be used for human food. The aim of this research was to explore the potential use of insects' flour as protein-rich ingredient for bakery products. Hermetia illucens, Acheta domestica and Tenebrio molitor were ground and used to replace 5% wheat flour in doughs and breads. The protein content of the insect flours ranged from 45% to 57% (d.m.) and fat content from 27% to 36% (d.m.). The inclusion of insects' flour affected the rheological properties (water absorption and stability), of dough during mixing, having less water adsorption. Breadmaking process could be carried out with all the composite flours. Breads containing A. domestica flour showed similar specific volume and texture parameters than wheat bread, but with higher content of proteins and fibers. Globally, results confirmed the usefulness of insects' flour for making breads with improved nutritional value.Industrial relevanceThis study evaluated the potential application of three different insects as protein source ingredients for bakery products. Results confirm that insects flour could be added to replace wheat flour in breads without significantly affecting dough properties and leading to breads with acceptable technological quality and improved nutritional profile.     

Enrichment of Egyptian ‘Balady’ bread. Part 1. Baking studies,physical and sensory evaluation of enrichment with decorticated cracked broadbeans flour (Vicia faba L.)

Physical, rheological and baking properties of decorticated cracked broadbeans‐wheat composite flours were studied and the acceptability of the Egyptian ‘Balady’ bread was evaluated by sensory tests. Decorticated cracked broadbeans flour (DCBF) was used to replace 5%, 10%, 15% and 20% of the wheat flour (WF) in bread. Farinographic studies showed that water absorption, arrival time and dough development time increased as the amount of DCBF increased, while dough stability time increased at 5% and 10% of DCBF substitution and decreased at 15% and 20% substitution. Also, the extensographic energy of the dough decreased as DCBF substitution increased, while the ratio between resistence and extensibility increased. There was a decrease in peak viscosity with increased amounts of DCBF. A reduction of the diameter and weight of bread loaf was observed as the amount of DCBF increased. The sensory properties of ‘Balady’ bread showed that at the two levels of 5% and 10% DCBF‐substitution, the ‘Balady’ loaves did not show any significant differences (P > 0.05). It is concluded that the replacement of bread flour (WF) with up to 10% decorticated cracked broadbeans flour produced acceptable Egyptian ‘Balady’ bread.