Studies on the quality of Turkish flat breads based on blends of triticale and wheat flour

The effect of different levels of triticale flour on the rheological and sensory characteristics of a range of Turkish flat breads made with blends of triticale with two bread wheat cultivars (K?nac? 97 and Daǧda? 94) was studied. Wheat flour was replaced with triticale flour at 20, 40, 50, 60 and 80% levels. Bread samples were tested for shape and symmetry, crust colour, crumb colour and structure, mouth‐feel, taste and aroma and flexibility. All bread types had high overall sensory scores and they were considered acceptable. Analysis of variance (anova ) and principal component analysis (PCA) showed that Daǧda? 94 and Triticale blends are more suitable than K?nac? 97 and Triticale blends for bazlama, yufka and lavash production. Results show that Triticale‐wheat flour blends can be successfully used for the production of flat breads. Dough and sensory properties of triticale‐wheat flour blends were highly cultivar specific and dependent on blend proportion.     

Characterisation of different typical Italian breads by means of traditional,spectroscopic and image analyses

In this paper a complete characterisation of four typical durum wheat breads produced in Italy was performed, from the starting semolinas to the final product, also considering the intermediate dough. An evaluation of the quality of durum wheat re-milled semolinas was carried out by means of routine investigations, together with nuclear magnetic resonance (NMR) and isotope ratio mass spectrometry (IRMS) analyses, that were also applied to dough ready for baking and bread to monitor the variations that occur during processing. The experimental data obtained from routine and spectroscopic determinations were investigated using multivariate statistical analysis to evaluate the possibility of differentiating flours, doughs and breads according to their geographical origin. Computerised image analysis was applied to quantify the crumb grain features of different bread types, and to try to characterise each bread type through a set of crumb morphological and colour parameters.     

Adequacy of different wheat cultivars for low-hydration bread making

BACKGROUND: There is considerable interest in recovering landraces as genetic resources and as raw materials in ecological production. Low-hydration bread, whose dough is submitted to a sheeting roll process, is commonly prepared in Spain and other countries. The aim of this study was to assess the adequacy of some landraces, compared with commercial cultivars and flours, for making this type of bread. Eight Spanish landraces, four wheat cultivars developed during the green revolution and three commercial flours were chosen, their alveographic and kneading behaviours were analysed and the characteristics of the resulting breads were determined. RESULTS: The best correlations were obtained in breads with improver. Flours with extreme alveographic behaviour differed markedly from the rest. When these flours were excluded from the analysis, the parameters best correlated with bread quality (when using improver) were strength, tenacity and development time. A significant correlation between flour colour, a genetic factor, and crumb colour was found. This correlation was higher in breads without improver. CONCLUSION When flours with extreme characteristics were removed, the protein quality characteristics of flours defined the quality characteristics of low-hydration breads.     

Dough and crumb grain changes during mixing and fermentation and their relation with extension properties and bread quality of yeasted sweet dough

Dough and crumb grain evolution of yeasted sweet dough, as affected by the combined effect of mixing (dough development) and fermentation times, and their relation to rheological properties and bread quality was studied. Structural changes of under or optimum developed dough, without fermentation, were related mainly to increments in extensibility (P > 95%), without a noticeable change in pH. At all mixing stages, fermentation duration increased R_m, whereas extensibility and pH decreased. When plotting R_m with bread specific volume, cell area, total cell area fraction or yellow crumb colour parameter (b*) simple mathematical models, with determination coefficients larger than 0.85 were obtained. Bread crumb image analysis showed that crumb cell size was not affected by mixing time, while fermentation duration had a direct influence on this parameter, increasing the proportion of the smallest and the largest crumb cells, without changing cell density, possibly as a result of Ostwald ripening, coalescence and separation‐redistribution mechanisms.     

Synergism between lipoxygenase‐active soybean flour and ascorbic acid on rheological and sensory properties of wheat bread

BACKGROUND: The interaction between lipoxygenase‐active soybean flour (LOX) and ascorbic acid (AA), on colour, rheological and sensory properties of wheat bread was studied with the aim of reducing the applied quantity of additives in bread formulations. RESULTS: The ascorbic acid (0–500 ppm) and active soybean flour (0–1%) mixture improved bread‐crumb colour by lowering the yellow hue in a higher proportion than those expressed by the components alone, characterising a synergistic mechanism (?_b = 15.1? (1.7 × LOX) ? (0.5 × AA) ? (5.8 × LOX × AA), where ?_b represent the estimated value for the yellow hue parameter). No differences in flavour and porosity were seen between the samples. As supported by the instrumental methods, breads made with active soybean flour and ascorbic acid (LOX + AA) had whiter crumbs and were softer and springier than controls as assessed by a trained sensory panel. In summary, the combination of both active soybean flour and ascorbic acid showed synergism, promoting a greater bleaching effect than when used alone. CONCLUSION: These results suggest the potential use of active soybean flour as a synergistic ingredient in the substitution of artificial additives in bread making. Since the interaction on the bleaching response was not linear and active soybean flour showed a higher iron concentration (66.40 ± 4.23 µg g^?1) than non‐active soybean flour (52.30 ± 0.40 µg g^?1), more studies are warranted to establish the biochemical mechanisms involved in this interaction. Copyright © 2007 Society of Chemical Industry     

Effect of different iron compounds on wheat and gluten‐free breads

BACKGROUND: Iron fortification of bread often results in sub‐optimal quality of the final product due to undesirable changes in the physical characteristics and sensory properties of the bread. In this study both the form of iron (soluble, insoluble or encapsulated) and the type of bread (wheat or gluten‐free) were varied in order to investigate the effect of iron and gluten on the product characteristics. RESULTS: The effect of iron on the quality characteristics of the breads investigated depended on iron type, but not on iron solubility. Colour, crust firmness, specific volume, cell number and uniformity as well as aroma were the attributes that were mainly affected in iron‐enriched wheat bread. In some cases, specific volume was 30% lower than that of the control sample, while cell uniformity was significantly lower, as low as 50% of the control sample in some fortified samples. In gluten‐free breads, differences between unfortified and fortified samples included colour, crust firmness, cell number, ‘moisture’ odour, metallic taste and stickiness. In some cases, the sensory scores were better for fortified samples. CONCLUSIONS: Differences due to iron fortification were less pronounced in gluten‐free compared to wheat breads. The choice of the appropriate iron compound which will not cause adverse quality changes is still a challenge. Copyright © 2010 Society of Chemical Industry     

Effect of Soybean 7S Protein Fractions, Obtained from Germinated and Nongerminated Seeds, on Dough Rheological Properties and Bread Quality

Germinated soybean flour has been proposed for use in bread making as a product to improve bread quality when small amounts are added to wheat flour. However, it is not clear which soybean components promote this action, and how these components may influence bread quality. The aim of this work was to evaluate the effect of the addition of soybean 7S protein fraction obtained from germinated and nongerminated seeds in dough rheological properties (farinographic and extensographic) and bread quality, including loaf volume, texture (firmness, compression force, resilience), colour (L*, a*, b*), crumb grain structure (cell density, mean cell area, shape factor), and consumer acceptance (sensory analysis). Results showed that this protein fraction just slightly affects bread quality, since no significant changes (P > 0.05) on bread volume and texture were obtained. Only crust and crumb colour were affected in a small amount, and a coarser crumb structure was also observed when adding 7S protein obtained from germinated soybean at its highest concentration. As the proportion of protein increased in the flour, both kinds of 7S fraction (germinated and nongerminated) were related to the increment in water absorption, as well as to the increment in extensographic maximum resistance to extension, specifically when adding 7S protein obtained from nongerminated soybean seeds. These results showed that the 7S soybean protein, as obtained in this work, is not related to the reported loaf bread quality improving effect of this legume when it is added in small quantities.     

百香果皮果胶提取工艺及其对面团和面包品质的影响

从百香果皮中提取果胶作为面包改良剂,以未添加改良剂和添加豆渣的面团为对比,通过质构仪分析百香果皮果胶对生面团延展性和面包坚韧性的影响。结果显示:百香果皮果胶提取的最佳工艺条件为:质量分数为0.45%的草酸铵、料液比1∶45(g/mL)、50 W超声波辅助提取90 min,果胶提取率为24.79%。质构测试结果表明:添加百香果皮果胶的面团拉丝长度、弹性、粘性和内聚性较大,而硬度较小,其面团品质最好。添加豆渣和百香果皮果胶均使面包的硬度和咀嚼性降低,有效改善面包的质构特性。Kramer感官评定结果表明百香果皮果胶面包最受消费者喜爱。     

山梨糖醇对面包储藏期间品质的影响

利用质构仪﹑低场核磁共振(LF-NMR)等方法研究山梨糖醇对面包储藏期间的品质变化以及水分含量的影响。结果表明:山梨糖醇的加入使得面团发酵速率有所下降,也能够显著降低面包的硬度和咀嚼性(P0.05),减小储存期间的老化度。LF-NMR测试表明山梨糖醇的加入能提升面包的持水性能。利用面包硬度拟合Avrami方程,面包的老化速率常数有所减小,且得到的相关系数较高,说明面包硬度是面包老化在质构上的表征。总体而言,山梨糖醇能提升面包的持水性能,改善面包的口感。     

Bread improvers: Comparison of a range of lipases with a traditional emulsifier

This study compares three generations of lipase enzymes with the emulsifier, diacetyl tartaric esters of mono-glycerides (DATEM), on white wheat flour bread. Baking recipes with addition of DATEM (4500 ppm), Lipopan F-BG (15 ppm), Gryndamyl Exel-16 (115 ppm), Lipopan Xtra-BG (25 ppm) and Lipopan 50-BG (27.5 ppm) were test-baked after 60 and 150 min fermentations, to study their effects on the baking characteristics of volume, oven rise, crust colour, crumb texture and colour, shelf-life, flavour and aroma. The enzymes and emulsifier preparation caused significant increase in bread oven rise and specific volume with the exception of Lipopan 50-BG, which failed to improve loaf volume in the short fermentation method. There was no significant difference between other lipase enzymes and DATEM as a bread volume improver. Increase in fermentation time resulted in increase in volume in all samples, except for Lipopan-Xtra.     

Effect of enzymatic crosslinking on the handling properties of dough as a function of NaCl levels for CWRS varieties,Pembina and Harvest

The effects of transglutaminase (TG) and glucose oxidase (GO) on the handling properties of model bread dough were examined at both normal (2% wt. by flour) and reduced (1% wt.) sodium chloride (NaCl) levels using two Canada Western Red Spring (CWRS) cultivars; Pembina and Harvest. The reduction of NaCl level had negative effects on dough rheology and stickiness, however, the inclusion of GO (0.001 and 0.01% by flour weight) or TG (only at the 0.5% by flour weight inclusion) was able to improve dough strength and reduce stickiness. GO appeared to be more effective than TG (at 0.01%) at equivalent concentrations for improving dough‐handling properties. Flour cultivar had significant effects; Harvest flour (weaker) was more impacted by salt reduction and enzyme inclusion compared to Pembina flour (stronger). Crosslinking assays showed significant differences in glutenin macropolymer (GMP) content in dough prepared with GO, and dough prepared with different flours. Additionally, significantly fewer free thiol groups were found in dough produced with GO compared to dough without any enzymes and those with TG. GO appears to have potential for use as a bread improver to reduce stickiness and improve the strength of bread dough produced at lower salt concentrations, especially for dough prepared with weaker flour cultivars.     

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.     

Bread crumb quality assessment: a plural physical approach

The aim of this study was the assessment of pan bread crumb quality attributes of commercial samples using a plural physical approach to better match consumer awareness. Static (texture profile analysis, firmness AACC and relaxation test) and dynamic (innovative oscillatory test) deformation techniques, image analysis, sensory analysis and colour measurements (colorimeter and Photoshop system) were used for white/whole commercial pan bread quality evaluation over 10 days of storage. Static (k ₁, k ₂, cohesiveness, springiness, hardness, chewiness and resilience) and dynamic (stress) bread crumb rheological properties were correlated illustrating that both techniques can be useful in evaluating crumb physical characteristics. In addition, sensory perceiveness with regard to softness and overall acceptability exhibited dependence with either dynamic stress or static firmness. Despite the fact that empirical measurements are closely linked to macroscopic features whilst dynamic tests are strongly linked to molecular characteristics, the obtained results support that both techniques are complementary since derived instrumental parameters are related to some sensory attributes. As data achieved using the proposed novel approaches might be better linked to the consumer awareness than those obtained from classical analyses, the obtained results are promising for a proper bread crumb quality assessment.     

面包改良剂功能与特性的研究（Ⅱ）

生产高品质的面包离不开优质的面包原料,诸如面粉、酵母、改良剂的使用等。本论述了面包改良剂的主要种类及其对面包的品质改良作用,并就国内外研究概况进行了分析和探讨。     

Impact of oleuropein on rheology and breadmaking performance of wheat doughs,and functional features of bread

Oleuropein (OP) is a polyphenol present in drupes and leaves of olive tree with health benefits and, as antioxidant, potentiality to alter gluten functionality. Effects of OP inclusion to wheat flour (0.01% and 0.02% on flour weight basis) on dough rheology and breadmaking performance, and bread features were investigated. Farinograph, uniaxial extension and shear rheometry (oscillatory and creep-recovery) were applied. Doughs containing OP were stronger, more elastic, and less sticky indicating the ability of OP to act as flour improver. The strengthening effect of OP on gluten led to the increase in bread volume and softer crumb compared to control. A lower crumb density of bread with the addition of OP was related to a higher in vitro glycaemic response. An increase in the antioxidant capacity of bread made with the phenolic compound was also found.     

Performance of wild Saccharomyces and Non-Saccharomyces yeasts as starter cultures in dough fermentation and bread making

The use of wild Saccharomyces and non-Saccharomyces yeasts might result in bread with different and attractive sensory characteristics. This study aimed to evaluate the performance of Saccharomyces and non-Saccharomyces yeasts as starter culture in dough fermentation to bread making and the physicochemical parameters and aromatic profile of bread. All 26 wild yeasts strains isolated from Brazilian Cerrado fruit and tree bark were osmotolerant, and 19.4% were able to ferment maltose. Candida tropicalis ART101.3 and Saccharomyces cerevisiae SC5952 had the best growth capacity under high concentrations of glucose and maltose. Also, they were resistant to lyophilisation. Kinetic parameters of bioreactor cultivations showed high cell growth and lower generation time with 10 g L⁻¹ maltose. Bread produced with C. tropicalis ART101.3 and the control bread had similar physicochemical properties and acceptance of consumers. Bread with S. cerevisiae SC5951 had a lower specific volume and a different colour than control bread; however, the consumers found no significant difference. More than 70% of the consumers demonstrated purchase intention of bread produced with both wild yeasts. The present study shows the potential of native Cerrado yeasts to be used and exploited in industrial processes and contributes to the diversification of bread starter cultures.     

Effect of hydrocolloids on gluten‐free batter properties and bread quality

The objectives of this study were to assess the effect of the addition of different hydrocolloids on gluten‐free batter properties and bread quality and to obtain information about the relationship between dough consistency and bread quality. Breads were made of rice, corn and soy flours and 158% water. Following hydrocolloids were added: carrageenan (C), alginate (Al), xanthan gum (XG), carboxymethylcellulose (CMC) and gelatine (Gel). Batter consistency, bread specific volume (SV), crumb analysis, crust colour, crumb hardness and staling rate were determined. Hydrocolloids increased batter consistencies: the highest value was obtained with XG, which doubled that of control batter, followed by CMC. Breads with hydrocolloid presented higher SV than control, especially with XG whose SV was 18.3% higher than that of control bread. A positive correlation was found between SV and batter consistency (r = 0.94; P < 0.05). Crumbs with Gel, XG and CMC presented higher cell average size. XG and CMC crumbs looked spongier. Breads containing hydrocolloid evidenced lighter crusts. Crumb firmness was decreased by XG and CMC addition, and staling rate was slower. Overall, XG was the hydrocolloid that most improved gluten‐free bread quality. These results show that, in formulations with high water content, batter consistency is strongly associated with bread volume.     

Identification of multiple grain image samples from tray

This paper presents a methodology to identify the different grain types from image samples of tray containing multiple grains using colour and textural features. The multiple grain images are segmented into individual grain images. From these images, eighteen colour and twenty‐four textural features are obtained. A neural network model is implemented for identification of bulk food grains. Five different types of grains namely, alasandi, green gram, metagi, red gram and wheat commonly used in Indian food preparations are considered in this work. The maximum and minimum food grain identification accuracies observed in this work are 94% and 80% for wheat and alasandi, respectively. The work finds application in development of machine vision system for grain identification, classification and grading.     

Pomegranate seed powder as a functional component of gluten‐free bread (Physical,sensorial and antioxidant evaluation)

The purpose of this study was to evaluate the effect of the addition of pomegranate seed powder (PSP) on physical, sensorial and antioxidant properties of gluten‐free bread. The PSP was incorporated at different levels (2.5%, 5.0%, 7.5% and 10%) into formula of gluten‐free bread. Control gluten‐free bread made without any addition of PSP was used for comparison. The results showed that the specific volume and springiness of gluten‐free breads increased, whereas hardness and chewiness decreased significantly with increasing PSP addition. The addition of PSP into gluten‐free bread decreased the lightness and yellowness of crumb and crust colour, while redness increased. Total phenolics content (TPC) increased from 46% to 181% with PSP addition (2.5%–10%). Moreover, antioxidant activity was significantly higher for bread with PSP. For bread with the highest percentage of PSP, the highest antioxidant activity was obtained. For sensorial and antioxidant activity, the optimum level of PSP addition was found to be 7.5%.     

Influence of phosphorylated rice flour on the quality of gluten‐free bread

The chemical modification of rice flour by phosphorylation is an alternative to improve the technological quality of bakery products. The aim of this study was to investigate the effect of phosphorylation process of rice flour on technological properties (specific volume, crumb and crust colour) of gluten‐free breads and the hardening of these breads during two storage temperatures (21 °C and ?24 °C). Breads were made with native rice flour, with phosphorylated rice flour and with wheat flour, used as control. The phosphorylation causes significant reduction in the synaeresis of pastes and in retrogradation tendency of rice flours, varying from 258.7 cP (native rice flour) to 122 cP (phosphorylated rice flour). The breads prepared with phosphorylated rice flour showed reduction in the hardness in both storage temperatures studied and effect on rice bread volume, crumb appearance and colour, demonstrating the possibility of use of the phosphorylated rice flour in gluten‐free breads.