Optimisation of flours for chapatti preparation using a mixture design

A mixture design was evaluated for the preparation of composite chapatti flours from two wheat cultivars, Mercia and Galahad, as single cultivars did not yield flours suitable for chapatti production. Physicochemical and rheological tests were applied to determine flour quality. Dough development time (Peak time) and dough stability increased and tolerance index decreased with increasing level of Mercia in the composite flour. Instron and sensory tests were applied to evaluate changes in softness of chapattis at different intervals of storage. Maximum response in texture softness was found with 500 g kg^?1 Mercia in the composite flour. Dough prepared from this composite flour showed low stickiness, moderate sheeting resistance and moderate subsequent shrinkage, making it of suitable sheeting quality for chapatti production. It yielded chapatti of soft texture whose scoop formation capability did not change significantly during storage. Copyright © 2006 Society of Chemical Industry     

Relationship of polymeric proteins with pasting,gel dynamic- and dough empirical-rheology in different Indian wheat varieties

The protein characteristics of flours from fifteen Indian wheat varieties were studied and related to pasting, gel viscoelasticity and dough properties. The analysis of polymeric proteins showed glutenins, gliadin and glutenin to gliadin ratio ranged between 28.14 and 40.44%, 45.33 and 55.83% and 0.50 and 0.89, respectively. Paste breakdown was low in flours with higher protein content. Viscoelastic properties of flour gels from different varieties showed significant variation and were dependent more on protein than amylose content. The gelation behavior of cooked pastes measured during cooling and holding at 10 °C was explained by an equation. Dynamic moduli of gels were positively correlated with total protein content and negatively correlated to the percentage of unextractable polymeric protein (UPP). Dough strength was positively related to UPP and glutenin content.     

Chapatti quality from British wheat cultivar flours

The aim was to study wheat flour parameters relevant to suitability for production of chapattis, made from British wheat cultivars. Wholemeal flours from eight British cultivars grown in UK differed in physicochemical and rheological properties, and were less suited to chapatti production than Mehrani, commercial wholemeal chapatti flour. Chapatti quality of Mehrani wholemeal flour was rated as excellent, hence this was used as a benchmark. Flours from cultivars Riband and Galahad gave weak dough whereas those from Fresco and Mercia yielded dough high in resistance to sheeting that contracted after rolling. Dough from Avalon, Hereward and Pastiche had moderate resistance to sheeting properties. Changes in softness of chapatti during storage were evaluated using an Instron testing machine. Evaluation by sensory panel indicated that all cultivars produced chapattis that were fair to good in sensory characteristics. Some correlations were found between sensory and instrumental attributes of chapatti.     

A farinograph study on the viscoelastic properties of sago/wheat flour dough systems

Doughs containing mixtures of sago and wheat flours of differing protein content at different levels of sago substitution (10, 15, 20, 25, 30, 40 and 50%) were prepared as follows: sago + high protein wheat (HPW) flour, sago + medium protein wheat (MPW) flour and sago + low ? protein wheat (LPW) flour. The viscoelasticity of doughs from control sago and wheat flours and sago/wheat flour mixtures was determined using a Braberder farinograph. It was found that arrival time increased with increasing protein content in the mixture. Peak time for control wheat flours and sago/wheat flour mixtures increased with increasing protein content. Dough stability, 20 min drop and water absorption were found to decrease as the sago proportion in the mixture decreased. The 50% sago/LPW mixture was unable to form a dough. Breakdown times for control HPW flour and HPW flour mixtures were the highest, followed by MPW flour and then LPW flour. However, breakdown time for control MPW flour was higher than that for HPW flour mixtures. The same trend was observed at all ratios of mixture over the whole experiment. Copyright © 2004 Society of Chemical Industry     

A Comparative Study of the Inter-Relationships Between Mixograph Parameters and Bread- Making Qualities of Wheat Flours and Glutens

The mixing characteristics and bread-making qualities of flours, reconstituted flours and glutens from a diverse range of wheat cultivars obtained from Canada, France and the UK, were investigated. Simple correlations were calcu-lated among Mixograph parameters, loaf volume, Glu - 1 quality scores, protein content, SDS-sedimentation volume and baking absorption. The results indicate that the mixing properties of flours from cultivars in the medium–strong range are significantly influenced by their protein contents. On the other hand, the mixing properties of ‘extra strong’ or weak flours are relatively less affected by their protein contents, and it appears that the protein quality primarily controls their behaviour during mixing. Gluten samples, other than weak glutens from cvs Riband and Corin, required a longer time to mix to peak dough resistance (PDR) than their corresponding flour or reconstituted flour samples. However, the differences in mixing time were more pronounced between ‘extra strong’ glutens and their corresponding flours or reconstituted flours. The Mixograph parameter PDR showed highly significant ( P< 0·001) correlations with loaf volume for flour, reconstituted flour and gluten samples. In each case, variation in PDR explained more than 65% of the variation in loaf volume, reaching about 83% for glutens. PDR was also significantly correlated with Glu - 1 quality scores. However, the mixing times for flours, reconstituted flours and glutens demonstrated no simple correlations with loaf volume. On the basis of the results, it appears that the 2 g Mixograph PDR value for flour or gluten may be used to assess flour or gluten bread-making quality. It may be used as a viable alternative to the baking test for the evaluation of the baking potential of flour or gluten, as well as an alternative to currently used ‘gel protein’-based pro-cedures for differentiating between ‘strong’ and ‘extra strong’ wheats.     

Flour quality and dough elasticity: Dough sheetability

Current practices in testing flours call for measuring dough strength, not elasticity. Sheeting is a common method for processing developed doughs, the elasticity of which governs dough’s sheetability as dough springs back exiting rollers. To characterise dough sheetability, a study was conducted testing 18 different doughs made from six different flours. Each dough was sheeted using an instrumented sheeter and data for exit sheet thickness and roll forces were captured under a range of sheeting conditions. The true rheological properties of doughs were measured and used to calibrate the ABBM constitutive model for dough (1). Numerical simulations of sheeting operations were conducted; the R² coefficients between measured and predicted sheet thicknesses and roll forces (vertical and horizontal) were nearly all >0.9. Relaxation times were derived from dough model parameters and revealed that flour quality for dough elasticity should be assessed by examining moisture effects on dough relaxation time.     

Cassava (Manihot esculenta Crantz) Flour Fortification with Soy Flour

A flour was prepared from “sweet”cassava tubers. Cyanogenic acid content was 24.4 mg/kg of flour. Proximate analysis was made; crude protein content was 2.1%. Soy flour with 53.8% protein was used to fortify cassava flour at 5, 10, 15, and 20%. Quality of the cassava flour protein was very low; addition of soy raised the quality. Protein efficiency ratio of 80% cassava-20% soy composite flour was 1.55 when fed to rats. Rats receiving diets with 100% cassava, and 95% cassava-5% soy lost body weight. Diets with 90% cassava-10% soy caused no change in body weight. Soy softened the dough made from cassava-soy flours. Therefore, the smaller amounts of water needed to maintain a uniform dough consistency with increased levels of soy were determined. Dough became darker, more red and more yellow with increased amounts of soy. Panel scores for dough were increased with increased levels of soy up to 15%. Scores for appearance and eating quality for dough with 20% soy were lower than scores for dough containing no soy.     

Characteristics of yellow alkaline noodles prepared from Korean wheat cultivar

Physicochemical properties of Korean wheat flours were evaluated to determine the effect of flour characteristics on yellow alkaline noodles by comparing commercial and imported wheat flours. Optimum water absorption, thickness, and color of noodle dough significantly correlated with protein content-related parameters of flour. Korean waxy wheats showed shorter cooking time (8 min) and softer texture of cooked noodles than other Korean wheats. Cooking time significantly correlated with protein content, optimum water absorption, and thickness of noodle dough. Hardness of cooked noodles positively correlated with protein content (r=0.614, p<0.01) and protein content related parameters. Cohesiveness of cooked noodles positively correlated with SDS-sedimentation based on a constant protein weight (r=0.437, p<0.05). Several Korean wheat cultivars showed comparable noodle making properties to commercial flour for yellow alkaline noodles despite of dark noodle color. Wheat cvs. Baekjoong, Jeokjoong, and Ol had softer and more elastic texture than other Korean wheats.     

LEGUME SUPPLEMENTED FLAT BREAD: NUTRITIVE VALUE, TEXTURAL and ORGANOLEPTIC CHANGES DURING STORAGE

Flat breads were prepared from wheat flour substituting chick pea and pigeon pea flours at 10 and 20% levels and their nutritive value, textural, organoleptic properties and storability studied. Dough development time and stability of supplemented flours increased; however, their water absorption capacity decreased. Dough handling was satisfactory at 10% supplementation of both the legumes but extra dusting was needed for sheeting at higher levels of pigeon pea. Supplemented flat breads had lower moisture but harder texture than the unsupplemented one, the hardness increased further upon storage. Sensory evaluation revealed that superior quality flat breads could be produced by supplementation of chick pea up to 20% and pigeon pea up to 10%. Protein Efficiency Ratio (PER) of supplemented breads was significantly higher than that of unsupplemented ones. Supplementation also resulted insignificantly improved haemoglobin content of the blood in rats.     

陕西省主要推广小麦品种配粉特性的研究

分析了陕西省15个推广小麦品种及其26个混配粉的面团流变学特性。结果表明，年际间和不同批次制粉间强筋小麦品质变化较大，中筋和弱筋小麦品质变化相对较小。不同混配方式配粉由于其面团流变学特性变化规律不同而产生不同的配粉结果。混配粉面团评价值、拉伸阻力和延伸性测定值与由基础品种估算的理论值无显著差异，而且有板显著正相关性。混配粉品质趋于混配品种平均值，并有“超高种”、“超低种”现象。陕253、绵阳19、小偃22、武农148等作为配粉品种较为理想。     

Effect of Rice, Corn and Soy Flour Addition on Characteristics of Bread Produced from Different Wheat Cultivars

Preparation and consumption of bread enriched with flours that contain appreciable amounts of protein, lysine, dietary fiber, and minerals will provide a healthy alternative to consumers and also a lowering of bread making cost in countries where wheat is not a major domestic crop. Addition of rice, corn, and soy flour to bread and durum wheat flours at 10, 20, 30, 40, 50% levels was carried out to examine the effects on the baking (specific volume, color, firmness) and sensory characteristics of bread. Dough rheological properties were also studied using Brabender Farinograph and Extensograph. Results of the present study suggest that incorporation of rice, corn, and soy in bread wheat flour up to a level of 10% (flour basis) and in durum wheat flour up to 20% produces bread without any negative effect in quality attributes such as color, hardness, and flavor and reasonable acceptance offering promising nutritious and healthy alternative to consumers. Increasing levels of substitution (30 and 50%) resulted in decreasing dough strength, extensibility, and loaf volume, due to the replacement of gluten by the added protein. Overall acceptability scores of these breads were found to be very low. The durum flour can be substituted with nongluten flours up to 10% more than the bread wheat flour because of its stronger gluten matrix and better dough rheological characteristics.     

Rheological properties of sheeted wheat flour dough measured with large deformations

Abstract

Large deformation rheological properties of a bread dough sheet were compared with baking quality of dough from the same sheet. Both rheological test and baking test could differentiate between dough made from a strong and a weak flour. Apparent viscosity at large deformation appeared to be the best predictor of the minimum sheeting requirement to obtain high loaf volume. This is similar to Mechanical Dough Development (MDD) mixing of dough where the mixing curve (apparent viscosity) is used to determine mixing requirement. Baking tests showed that loaf quality (volume and crumb texture) for bread made with sheeting was different from bread made with MDD mixing, particularly when dough was developed beyond the minimum sheeting requirement. These differences indicate that dough development (or over‐development) by sheeting may occur through a different mechanism than by MDD mixing.     

EFFECT OF PROCESSING CONDITIONS ON THE QUALITY OF SOUTH INDIAN PAROTTA— AN INDIAN TRADITIONAL FOOD

Parotta is a wheat flour based, circular and creamish white colored south Indian traditional product. It possesses light brown spots on the surface, a soft pliable hand‐feel, soft and slightly chewy texture, with distinct layers, optimum oiliness, easy breakdown in the mouth, and with typical pleasant taste and aroma. A sensory score card, based on the above parameters, was prepared to assess the quality of parotta. The survey of the quality characteristics of parotta from different commercial sources showed variation in the overall quality score from 40‐75 for the maximum score of 100 indicating a lack of consistency in the quality of parotta. Parotta dough water absorption was standardized using a farinograph. The effect of mixing period (1, 4 and 8 min), rest period (0, 30 and 60 min), sheeting thickness (2.5, 5.0 and 7.5 mm), baking time (1, 2 and 3 min) and baking temperature (175, 205 and 230C) on the quality of parotta was studied. The optimum processing conditions arrived at for the preparation of parotta are mixing time, 4.0 min; rest period, 30 min; sheeting thickness, 5 mm; baking time, 2.0 min, and baking temperature, 230C. The overall quality score of parotta prepared from the flours varying in protein quantity, quality, dough mixing time and stability was highest at 4.0 min mixing time.     

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.     

小麦面粉的3D打印特性

本实验以8种不同蛋白质量分数小麦面粉为研究对象,通过测定其理化特性、糊化特性、混合特性、流变特性及3D打印特性,研究小麦面粉不同品质特性与3D打印特性的关系。结果显示,蛋白质量分数对小麦面粉的3D打印特性有显著影响,蛋白质量分数在9%～10%时（ZY原味小麦粉、BN 4199小麦粉和XL中式面点粉）打印效果较好,制品整体形状规则、表面平整、纹路清晰,与模型的符合程度较高。面团的损耗模量（G’’）影响其挤出行为,而储能模量（G’）影响其支撑三维结构的能力,ZY原味小麦粉面团的损耗角正切值（tan δ）较大,有利于面团挤出成型;XL中式面点粉G’较大,有利于面团打印后保持自身的形状。在选用的8种小麦面粉中,XL中式面点粉的蛋白质量分数为9.33%,与设计的30 mm×30 mm×10 mm模型相比,其打印体积误差仅为0.26%。打印制品蒸制熟化后在X轴和Y轴方向上长度略有增加,但Z轴方向上长度略有减小,且发生一定程度的褐变。综上,小麦面粉作为3D打印材料是可行的,这有利于拓展3D打印技术在食品领域的应用。     

Dough properties and baking characteristics of white bread,as affected by addition of raw,germinated and toasted pea flour

Thermal and non-thermal processing may alter the structure and improve the techno-functional properties of pulses and pulse flours, increasing their range of applications in protein-enhanced foods. The effects of germination and toasting of yellow peas (Pisum sativum) on flour and dough characteristics were investigated. Wheat flour was substituted with raw, germinated and toasted pea flour (30%). The resulting bread-baking properties were assessed. Toasting increased dough water absorption and improved dough stability compared with germinated and raw pea flour (p < 0.05). This resulted in bread loaves with comparable specific volume and loaf density to that of a wheat flour control. Significant correlations between dough rheological properties and loaf characteristics were observed. Addition of pea flours increased the protein content of the breads from 8.4% in the control white bread, to 10.1–10.8% (p < 0.001). Toasting demonstrated the potential to improve the techno-functional properties of pea flour. Results highlight the potential application of pea flour in bread-making to increase the protein content.     

Quantitative and Qualitative Assessment of Wheat Gluten Proteins and their Contribution to Instant Noodle Quality

This study was carried out to examine the effect of quantity and quality of wheat gluten proteins on the quality attributes of instant fried noodles. Dough development time, dough stability, SDS sedimentation volume, gluten index and Resistance to extension/Extensibility (R/E) ratio were found to be positively correlated with glutenin content, whereas negatively associated with the quantity of gliadin sub-fractions. Medium strong flours were found most suitable for noodle preparation. The weaker flours from cultivars HW 2004 and C 306 having HMW-GS composition of Null, 2+12 and 20 alleles expressed at Glu-A1, B1 and D1, respectively could not withstand sheeting, resulted in rough surface and high breakage of noodles. The best noodle cultivars DBW 16 and WH 542 had 5+10 glutenin subunits at Glu-D1, however, differed in subunits expressed at Glu-A1 and Glu-B1 loci. Oil uptake and cooking time of noodles varied considerably from 15.4 to 22.7% and 2.0 to 4.0 min, respectively. Oil uptake in noodles was positively correlated with dough softening, however, all the parameters related to gluten quality and strength were negatively associated with the oil uptake. Cooking time of instant noodles was found to be highly associated with protein content (R² = 0.778) of flour, gluten quality and strength. Hardness or firmness of cooked noodles was found to be significantly linked with SDS sedimentation volume (R² = 0.725), gluten index (R² = 0.610), glutenin content (R² = 0.619), gliadin content (R² = ?0.567), R/E ratio (R² = 0.532) and gliadins/glutenins (R² = ?0.605) ratio.     

Rheological properties of wheat flour doughs I.—Method for determining the large deformation and rupture properties in simple tension

A method and an apparatus are described for determining the large deformation and rupture properties of wheat flour doughs in simple tension. Dough rings are submerged in a liquid of matching density to prevent the dough from deforming under its own weight and are stretched at constant rates of extension until rupture occurs. Stress-strain curves obtained at different temperatures and extension rates on doughs prepared from a medium strength flour and a weak flour are presented, and the effects of rest period, mixing time, and mixing atmosphere on dough properties are discussed.     

Changes of chemical composition and dough rheology in two fractions of sieve-classified Polish spring wheat flour

The study of chemical composition and dough rheology changes in sieve-classified two fractions (up to 60 and 60-240 microm particles) of wheat flour was the subject of this study. The straight grade flours were obtained by the milling of three Polish varieties of spring wheat, differing in particle size index (PSI) values. The flours were separated with the use of an SZ-1 laboratory sifter. The yield of fine fraction was in the range 50.0-55.7%. The obtained fractions were assayed for the content and composition of free lipids, gluten proteins, damaged starch, ash, water absorption and amylograph viscosity. Dough rheology (extrusion in OTMS cell, alveograph and farinograph tests) and baking trials were also performed. The content of free lipids, including the non-polar and phospholipids was lower and the content of glycolipids was higher in fine flours. Those fractions were more rich in linoleic acid but the lower content of oleic and linolenic acids resulted in a higher oxidizability index of free lipids. Fine flours contained less ash and significantly more damaged starch. At the same time, they were characterized by a higher content of wet gluten, water absorption, amylograph viscosity and better dough parameters. This was reflected in the bread volume, which was higher by 6.3-10.7%. The influence of the changes in composition and the content of free lipids upon the rheology of the dough after the 90 days flour storage has not been defined unambiguously and requires further research.     

Improving wheat for bread and tortilla production by manipulating glutenin‐to‐gliadin ratio

Gluten, starch, water soluble material, and glutenin‐rich and gliadin‐rich proteins were extracted from three Canadian wheat cultivars representing the Canada Western Red Spring (CWRS) (cv Roblin), Canada Western Extra Strong (CWES) (cv Glenlea) and Canada Prairie Spring (CPS) (cv AC Crystal) classes having glutenin‐to‐gliadin (Glu:Gli) ratios of 0.70, 0.75 and 0.85 respectively, all giving the same high‐molecular‐weight glutenin subunit score (Glu‐1 score) of 10. The resulting fractions were reconstituted to produce 18 mixtures of flour components, representing all combinations of Glu:Gli ratio and protein content observed in the original three flours. Dough rheological properties and baking (bread and tortilla) performance were determined using small‐scale techniques. Within any of the cultivars, increasing the Glu:Gli ratio in a reconstituted dough system had significant effects on dough and end‐use properties, causing increases in mixograph development time (MDT), maximum resistance (Rmax), pan bread loaf volume, tortilla dough maximum resistance and cooked tortilla puncture force. The CWRS wheat Roblin, proved to be best suited for pan bread at higher protein content and higher Glu:Gli ratio, and also produced a high protein tortilla of large diameter at a Glu:Gli ratio of 0.70. The CPS flour, AC Crystal, was good for making tortillas at protein contents of 110–130 g kg⁻¹ and at its original ratio of 0.85. The CWES wheat Glenlea, did not perform as well in bread or tortilla‐making but in its role as a blending wheat, altering the Glu:Gli ratio of Glenlea to 0.70 may have an advantage by lowering mixing time without compromising baking properties. Manipulating the Glu:Gli ratio may make a wheat cultivar suitable for a particular end‐product. For the Department of Agriculture and Agri‐Food, Government of Canada, © Minister of Public Works and Government Services Canada 2005. Published for SCI by John Wiley & Sons, Ltd.