Flour quality tests for selected wheat cultivars and their relationship to Arabic bread quality

Analytical and rheological parameters were established for flours from nine selected wheat cultivars, each covering a range of protein contents. Arabic and pan breads were baked from these flours and baking quality was determined. Wheat cultivars were found to differ in their suitability for Arabic bread production. Within cultivars the relationship between protein content and Arabic bread score was best described by a quadratic equation. Traditional flour quality tests do not adequately describe the flour quality requirements for Arabic bread as clearly as for pan bread. Ranges and optimum values for a number of parameters can be set to describe flours most likely to be suited to the production of Arabic bread. However, for reliable evaluation of baking quality for Arabic bread, flours fitting the prescribed range must be test baked.     

Incorporation of pulse flours of different particle size in relation to pita bread quality

BACKGROUND: To increase pulse consumption, pita bread was fortified with pulse flours milled from green lentils, navy beans and pinto beans, which were ground to produce fine and coarse flours. Pita breads were prepared using composite flours containing pulse flours (25, 50, 75%) and wheat flour or 100% pulse flours and adjusting the amount of water required for mixing based on farinograph water absorption. Pita bread quality was evaluated according to diameter, pocket height, specific loaf volume, texture and crust colour. RESULTS: Blends made from pulse flours with coarse particle size showed higher rates of water absorption. All composite flours and 100% pulse flours produced pitas with pockets, confirming their suitability for this product. Crust colour of pitas was affected less by navy bean flour than by lentil flour. Pita breads made with pinto bean flour were superior in texture. Overall, navy and pinto bean flours appeared more suitable for pita bread. Flours with coarse particle sizes produced pitas with better colour and texture. Sensory parameters of pitas containing 25% coarse pinto or navy bean flour were as good as or better than those from the wheat control. CONCLUSION: Acceptable pita breads can be made using pulse flours, although the substitution level is limited to 25%. Copyright © 2012 Society of Chemical Industry     

不同品种马铃薯对马铃薯-小麦复合馒头品质特性的影响

本文以22个品种的新鲜马铃薯为原料制备马铃薯全粉,并对马铃薯全粉的基本成分进行了分析和比较;然后以22个不同品种的马铃薯全粉为原料制作马铃薯-小麦复合馒头(马铃薯全粉:小麦粉=3:7),并对其比体积、高径比、气孔结构和质构特性进行了分析和比较。结果表明,不同品种马铃薯-小麦复合馒头的比体积、高径比、气孔特性和质构特性存在显著差异性(p0.05)。高径比和比体积均较高的品种是紫花白、夏波蒂、陇薯6号、陇薯7号、中薯2号;气孔密度和气孔表面积分率都较高的品种是一点红、青薯9号、大西洋;硬度和咀嚼性都较好的品种是一点红、费乌瑞它、青薯6号、青薯9号、大西洋。综合考虑馒头的感官和物理特性,一点红、青薯9号和大西洋3个品种比较适合替代小麦粉,制得体积较为理想、硬度较低、气孔结构较好的馒头。     

Influence of genotype and protein content on the baking quality of hearth bread

The relationships between protein content and quality and the loaf characteristics of hearth breads made from the respective flours were investigated for 20 wheat genotypes, comprising both commercially grown cultivars and advanced breeding lines, grown in 1997 and 1998. In both years the average protein content was increased by increasing the level of nitrogenous fertiliser application, this effect being more pronounced in 1997 than in 1998. Grain samples were milled and evaluated for endosperm hardness, protein content, SDS sedimentation volume, mixing properties and baking quality determined by a hearth bread baking test using optimal mixing and fixed proving time. When producing hearth bread, both the form (height/width) ratio and loaf volume are critical external characteristics. Genotype differences, mainly due to differences in protein quality, were more important for both form ratio and loaf volume than differences in protein content. The dough development time of the Farinograph, operated at high speed (126 rev min^?1), was the best indicator of heart bread baking quality, giving high positive correlations to both the volume (r = 0.89) and form ratio of the loaf (r = 0.90). Climatic differences between the two years, in particular temperature during ripening, also affected the quality parameters studied. Copyright © 2004 Society of Chemical Industry     

Effects of flour from different barley varieties on barley sour dough bread

Twenty flours from 16 different barley varieties cultivated in 1990 and 1992, and a Swedish reference flour, were fermented by Lactobacillus plantarum A1 to sour doughs. Barley breads (40% barley/60% wheat flour) from each flour type were baked with and without an admixture of barley sour dough in order to investigate how the sour dough admixture would affect the baking properties. A trained panel carried out sensory evaluation by conventional profiling on breads made from three of the barley varieties and the Swedish reference flour, made with and without sour dough admixture.

The barley varieties influenced both the sour dough properties and the properties of the barley bread. The pH of bread with sour dough ranged from 4.6 to 4.8 as compared to 5.4 to 5.6 in bread without sour dough. The acidity of the breads with sour dough ranged from 4.1 to 5.0 ml NaOH/ 10 g bread crumb as compared to 2.4 to 3.6 in breads without sour dough. In 14 of the twenty bread types an addition of sour dough lowered the bread volume. Breads with a sour dough admixture scored higher for total taste and acidulous taste than breads without sour dough. The β-glucan content of the flours had no significant influence on the sour dough or the sensory characteristics of the bread, except for the breadcrumb colour.     

Influence of maize flour particle size on gluten‐free breadmaking

BACKGROUND: Maize, one of the suitable grains for coeliac consumption, is, together with rice, the most cultivated cereal in the world. However, the inclusion of maize flour in gluten‐free bread is a minority and studies are scarce. This paper analyses the influence of different maize flour types and their particle sizes on the quality of two types of bread without gluten (80% and 110% water in the formulation) obtained from them. We also analysed the microstructure of the dough and its behaviour during the fermentation. RESULTS: Finer flours had a lower dough development during fermentation in all cases. Among the different types of flour, those whose microstructure revealed compact particles were those which had higher specific bread volume, especially when the particle size was greater. Among the formulations, the dough with more water gave breads with higher specific volume, an effect that was more important in more compact flours. The higher volume breads had lower values of hardness and resilience. CONCLUSION: The type of corn flour and mainly its particle size influence significantly the dough development of gluten‐free bread during fermentation and therefore the final volume and texture of the breads obtained. The flours having coarser particle size are the most suitable for making gluten‐free maize bread. © 2012 Society of Chemical Industry     

不同粒径小米粉对面团流变特性及馒头质构特性的影响

为研究小米粉添加对面团流变特性和馒头制品质构特性的影响,分别选取不同粒径的粳性和糯性小米粉,利用损伤淀粉测定仪、快速黏度分析仪等对不同小米粉的损伤淀粉含量和糊化特性进行分析,通过流变仪测定小米面团的流变学特性,结合扫描电镜观察小米面团微观结构变化,并利用质构仪测定小米馒头的质构特性。结果表明：随着小米粉粒径的减小,多数品种小米粉（除冀谷39和汇华金米）损伤淀粉的碘吸收率增加;受直支比的影响,相同目数下,粳性小米粉的峰值黏度、谷值黏度、最终黏度和回生值较糯性小米粉大。流变学研究表明,除汇华金米和冀谷39,储能模量与损耗模量随角频率增加总体上升。扫描电镜观察发现小米粉的添加使面团结构更加松散。小米粉的添加会对馒头质构性质中硬度、咀嚼性和弹性等有一定程度的负面影响。主成分分析表明馒头咀嚼性、损伤淀粉、峰值黏度、谷值黏度、最终黏度、崩解值和回生值可作为区分粳糯品种和馒头品质特征的指标。     

Modelling and optimization of quality and costs on empirical data of hearth bread

Mathematical programming is an optimization technique, which can be used to simultaneously ensure several qualities of a product (cost, chemical composition, product characteristics, etc.). This requires mathematical models for the qualities, and especially different characteristics of a product may be challenging to model. One approach is to make empirical models based on data from experimental designs. In the present paper hearth breads are studied. The protein quality and protein content of the wheat flour have together with the mixing and proving time been found critical for hearth bread characteristics. By adjusting the process settings according to wheat flour properties, hearth breads within acceptable quality limits may be made from very different flours. A mixture-process design was constructed and 99 hearth bread batches were made. Models for hearth bread characteristics and production costs were estimated and optimized by mathematical programming. The study also considers how model uncertainty and different pricing systems of wheat flours and capacity costs influence the optimal solutions.     

大豆粉对馒头品质影响的研究

通过向小麦粉中添加全脂豆粉、脱脂豆粉及大豆蛋白,来研究其对小麦粉及馒头品质的影响.结果表明:随着全脂豆粉、脱脂豆粉及大豆蛋白使用量的增加,小麦粉湿面筋含量与沉降值逐渐下降,馒头的比容逐渐减小,品质逐渐变差;但当全脂豆粉与脱脂豆粉添加量在10%以内,大豆蛋白的添加量在5%以内时不会对馒头的品质产生不良影响,还可以弥补馒头中必需氨基酸特别是赖氨酸的不足,提高馒头的营养价值.     

Effect of Extruded Wheat Germ on Dough Rheology and Bread Quality

Wheat germ, a by-product of the milling industry, has interesting nutritional properties. However, it has limited use due to a high risk of rancidity, which could be reduced by using certain thermal treatments such as extrusion. The aim of this study was to investigate how wheat germ extrusion affects the changes induced by its addition to bread dough. For this purpose, different quantities of extruded or raw wheat germ (2.5, 5, 7.5, 10, and 20?g/100?g flour) were added to bread dough. Rheological characteristics of the dough and final quality characteristics of the bread were analysed from both the physical and the sensory points of view. Wheat germ addition increased water absorption and development time but decreased stability after over-kneading, dough tenacity, extensibility, and dough alveographic strength. The addition of extruded wheat dough improved stability and decreased extensibility and strength. Bread made from dough with added wheat germ presented decreased volume, cohesiveness, and elasticity and increased firmness. However, extrusion increased the volume of breads with added wheat germ and improver and decreased firmness. All breads obtained positive acceptability scores in sensory analysis, although wheat germ addition (10?g/100?g flour) slightly decreased texture, appearance, and overall acceptability scores of breads. Germ extrusion therefore improves dough rheology and bread quality and constitutes a suitable treatment to stabilise wheat germ in bread dough.     

顶空固相微萃取- 气质联用分析小麦馒头制作过程中的挥发性成分变化

为研究小麦挥发成分在加工过程的形成变化,选用具有代表性的3种不同筋力小麦品种--普冰143、晋麦47、西农9817,采用顶空固相微萃取技术萃取其小麦粉、发酵面团和馒头的挥发性成分并进行气相色谱-质谱分析鉴定。结果表明：普冰143、晋麦47、西农9817小麦粉检测出23种相同的挥发性成分,分别占总量的84.01%、77.82%和82.28%,其中主要成分为萘、1-甲基-萘、(Z)-2-丁烯二酸二甲酯、1,7-二甲基-萘、2-甲基-萘;发酵面团中检测出共同成分18种,分别占总量的80.99%、71.65%和70.44%,主要成分为乙醇、萘、1-甲基-萘、丁二酸乙基甲酯、苯乙醇;馒头中检出26种相同的挥发性成分,分别占总量的80.26%、75.99%和80.43%,主要成分为萘、1-甲基-萘、2-戊烷基-呋喃、乙醇、壬醛。不同筋力小麦制品之间的挥发性成分存在差异,但大部分主要成分相同。从小麦粉到馒头的制作过程中,挥发性成分发生明显变化,其中烃类物质相对含量明显减少而醇类物质种类和相对含量均增多。     

Wheat bread enrichment with hard-to-cook bean extruded flours: nutritional and acceptance evaluation

This study describes the enrichment of wheat bread with hard-to-cook black bean (BBEF) and cowpea (CEF) extruded flours. Breads containing 10% BBEF and 10% CEF presented increase of, respectively, 9% and 10% in protein content. In addition the fiber content was 2.6 higher in 10% BBEF bread and 2.2 higher in 10% CEF bread in comparison with standard bread. Despite protein and fiber increasing, the energetic value of substituted breads remained unchanged. An increase in the substitution to 15% resulted in decrease of specific volume and density of the breads. Results of sensory analysis to 10% BBEF bread presented overall appearance scores higher than standard bread and overall flavor acceptance very similar to standard. A total of 10% CEF bread presented similar appearance to those standard bread and 73% overall flavor acceptance. It is interesting to point out that distribution of 10% CEF bread overall flavor scores showed 3 distinct levels of consumer's sensibility. Practical Application: Breads enriched with extruded bean flours presented fiber and protein content improved and a very good consumer's acceptance. These results indicate that extruded bean flours constitute ingredients nutritionally and economically viable for technological application in breads elaboration, conferring improvement of nutritional characteristics without changing sensory attributes.     

Characterisation of traditional Albanian breads derived from different cereals

The long isolation of Albania and the scarcity of raw materials has traditionally led to the production of bread from crops other than wheat, like maize, which is the basic ingredient for maize bread (bukë misri), rye, which is used to prepare rye bread (bukë thekre), and chick-pea, used in chick-pea bread (bukë me qiqre). Today, these traditional breads are accompanied by other types, such as brown bread from soft wheat (bukë zize). In the present work, the traditional Albanian breads were characterised in order to assess their quality. The results obtained indicated that the protein content reflected the characteristics of the raw material used, being higher in the chick-pea bread and in bread made from high extraction rate wheat flour, while both fat and yellow pigment levels were higher in maize bread. A high humidity value was found in many of the breads examined, especially in maize bread, with consequent risks of moulds and a shortened shelf-life.     

Applicability of DATEM for Chinese steamed bread made from flours of different gluten qualities

BACKGROUD: The diacetyl tartaric acid ester of monoglycerides (DATEM) is an anionic oil‐in‐water emulsifier. The effects of DATEM on bread vary with the type of flour. However, there is insufficient information concerning the effects of DATEM on the qualities of Chinese steamed bread (CSB) even though it is also sold as a CSB improver. RESULTS: The effects of DATEM on CSB varied with flours. The overall qualities of CSB made from either weak or strong wheat flours were improved by the use of the additive, but the effects for medium strong flours were slight and uncertain. The effects of DATEM on individual parameters, such as specific volume, skin and inner structure, were similar to those on overall quality. The addition of DATEM increased the gluten strength and the dough stability of weak flour, whereas it weakened gluten strength and strengthened dough stability of strong flour. The addition of DATEM weakened the gluten strength and gave variable effects on dough stabilities for two medium strong flours. CONCLUSION: The effects of DATEM on CSB quality varied with flour type, by affecting flour characteristics, such as gluten strength, dough stability and lipid content. Copyright © 2008 Society of Chemical Industry     

Use of durum residue flour,a lower value product of durum milling,by incorporation into wheat flour dough without deterioration in baking quality

BACKGROUND: During the milling of durum wheat to semolina, about 10–15% of total products produced is residue flour, a lower value product than the semolina. This study investigated the potential for using the durum residue flour as an additive in bread‐making to improve its potential commercial value. RESULTS: Incorporation of residue durum flour from 102 breeding lines into a low protein flour and standard bakers' flour at 20% incorporation improved the bake loaf volume with minimal change in Mixograph dough mixing time and peak resistance in many of the lines tested. Loaf yellow b was always increased even with only a 10% incorporation. Baking flours can tolerate 20% incorporation with no deleterious affects on loaf volume and bake score. CONCLUSION: The results show a potential for using the lower value durum residue flour for baking bread of acceptable quality with a slightly higher yellow colour. This would improve the profitability for the miller and provide alternative ingredients to the baker for preparing specialty breads. Copyright © 2008 Crown in the Right of the State of New South Wales and Society of Chemical Industry     

Relationships between biochemical and quality-related characteristics of breads, resulting from the interaction of flour, microbial starter and the type of process

 The possible relationships between biochemical characteristics [total starch, sugars, low-molecular-weight dextrins (LMWD), acetic and lactic acids, soluble solids and crumb-swelling power] and characteristics related to the quality of wheat bread (volume, texture and sensory quality scores) have been investigated. Variables influencing the possible interactions occurring were the type of flour (white and whole-wheat flours), the starter microorganism (Lactobacillus brevis, L. plantarum) and the type of process used to introduce the lactobacilli inoculum (sourdough, straight). The main factor explaining variability of data was related to sensory quality attributes and physical characteristics of the breads. The second factor was related to LMWD and the third to the acidity and lactic acid content of breads. The first factor permitted separation of the bread samples into two groups on the basis of flour extraction rate, whereas LMWD allowed differentiation between white breads made with sourdough or straight processes. Cluster analysis included the level of acidity and the lactic acid content as additional factors grouping control breads (without starter) together with breads made using a straight process. The best canonical correlation was established between the physical characteristics of breads and carbohydrates, soluble solids and crumb-swelling power. The first pair of canonical variables between two sets of experimental variables showed a squared correlation coefficient of 0.986. Received: 15 July 1996     

Suitability of various australian wheats for chinese-style steamed bread

Three methods of preparation of steamed bread on a laboratory scale were evaluated to determine the one most suitable for discriminating between flour samples. The preferred method was then applied to a number of wheat varieties at different protein levels to select the most suitable ones for this product, and to determine the key analytical parameters of the most suitable flour. Flour colour and protein content appeared to be more important than other physical and chemical properties. Flour samples with high protein content (greater than 12%) and strong doughs gave bread with a wrinkled surface and dark colour, whereas low protein (less than 10%) soft wheat flours gave poor texture and eating quality, although the surface was smooth. It is suggested that flours of medium protein content (10–12%) and medium dough strength are the most suitable for steamed bread. Processing conditions affected steamed bread quality. Blending of high protein hard strong wheats with soft weak wheat could be practical for preparing flour for steamed bread.     

Analysis of volatile compounds in polished-graded wheat flour bread using headspace sorptive extraction

Flavor compounds are one of the very important factors for the taste of commercial breads, and then the volatile flavor compounds in the present novel polished-wheat-flour breads were determined by headspace sorptive extraction method to develop the baking properties, comparing two baking procedures of straight-common- and sourdough-methods. The polished flours of outermost, middle and innermost fractions, and common flour, CW were used. There were some differences on the compounds and proportions of volatile flavors in all flours between the both methods. The sourdough-method increased the proportions of acids and aldehydes in crust, but decreased those of alcohols and methoxybenzenes identified in the outermost fraction, rather than the straight-common-method. In addition, the sourdough-method lowered the amounts of some compounds related to oxidation products from unsaturated fatty acids and metabolites of species with moldy grains, as compared with the straight-common-method. Furthermore, the amounts of 2-methylpropanol (iso-butanol) and 2-phenylethanol (β-phenyl-ethyl-alcohol) that have been known as favorable flavor compounds on breadmaking distinctly increased in polished flour breads than CW bread, regardless of baking methods. Therefore, the sourdough-method with lactic acid fermentation would be suitable baking procedure for polished flours from the viewpoints of flavor properties. Furthermore, the utilization of sourdough-method for polished flours from middle and innermost fractions might be appropriate to taste and texture of consumers’ request for bread qualities.     

Effects of particle size in wasted bread flour properties

Bread is wasted at different stages in the food value chain, mainly in industry and retail markets. Wasted bread can be milled into flour to be used in the elaboration of other food products. Milling can generate flours with different particle sizes that influence their properties. This study analysed the effect of particle size (200, 500 and 1000 μm) on the hydration, pasting and gel properties of flours elaborated with four different stale breads. Bread flours show a higher cold water absorption capacity and a lower oil absorption capacity than wheat flour. No differences in water absorption properties after heating were observed. The viscosity curves of bread flours presented lower values than wheat flour curves, and the gels obtained were weaker. Bread flour properties were not influenced by different particle sizes. Therefore, a less aggressive milling, with a lower energy cost, can generates flours with properties similar to finer flours.     

Wheat bran particle size effects on bread baking performance and quality

Commercial hard red spring, hard red winter, soft white and durum wheat brans were used to evaluate the particle size effect of wheat bran on bread baking performance and bread sensory quality. Three different particle size bran samples were obtained from each bran by grinding, not by sifting, the bran samples. The bran samples were similar in chemical composition, but different in particle sizes. Results of baking experiments showed that breads containing fine bran had lower specific loaf volume and darker crumb colour than breads containing coarse or medium size bran. Sensory test panellists found that fine bran contributed smoother crust appearance and less gritty mouthfeel than the coarse bran. The sensory panel also indicated that breads containing soft white wheat bran had significantly better flavour and mouthfeel than breads containing hard red spring wheat bran. © 1999 Society of Chemical Industry