BAKING PERFORMANCE OF 1BL/1RS SOFT RED WINTER WHEATS

Baking performance of nine 1BL/1RS soft red winter wheat (SRWW) lines and six non‐1BL/1RS lines was assessed during two crop years, 1995–96 and 1996–97, and at two locations, Blacksburg and Warsaw, Virginia. The 1BL/1RS flours produced cookies with significantly smaller diameters than non‐1BL/1RS flours (p ≤ 0.0026) across both growing years and locations. There was a highly significant negative correlation (r =?0.709) between cookie spread and alkaline water retention capacity (AWRC) of SRWW flours. Overall, there was no significant difference (p = 0.2552) in biscuit volume of 1BL/1RS and non‐1BL/1RS flours. There were no significant differences in cake volumes of 1BL/1RS and non‐1BL/1RS flours when data from both years and locations were combined, p = 0.0710; or when Blacksburg and Warsaw locations were considered separately, p = 0.2009 and 0.1882, respectively. Finally, there were no significant differences in the texture of cakes made from 1BL/1RS and non‐1BL/1RS flours regardless of growing year or location. These results suggest that the 1BL/1RS translocation significantly reduces the cookie spread of SRWW flours but has no significant impact on biscuit or cake quality.     

Origin and practical significance of the sticky dough factor in 1BL/1RS wheats

When translocated into wheat, the short arm of the 1R chromosome of rye carries with it linked resistance genes to powdery mildew, stripe rust, leaf rust and stem rust. The translocation is also reported to increase yield potential of hard wheats. However, many doughs made from some 1BL/1RS hard wheats are unacceptable for breadmaking purposes because of excessive stickiness and mixing intolerance. 1BL/1RS wheats may be sticky because of: the inheritance of secalin proteins from rye and absence of key glutenin subunits; higher amounts and/or differences in the composition of cell wall polysaccharides, β‐glucans and pentosans; and/or the presence of a ferulic acid ester moiety residing with the water‐soluble fraction of 1BL/1RS flours. None of these hypotheses has been proven or disproven, to date, as a cause of excessive stickiness. Investigators have found that 1BL/1RS doughs are not uniformly sticky and are in some instances less sticky than non‐1BL/1RS doughs. Significant genotype–environment interactions have been reported for dough stickiness and flour quality characteristics of 1BL/1RS wheats. Investigators have generally failed to find significant differences in the breadmaking performance of 1BL/1RS and non‐1BL/1RS hard wheats despite a report that 1BL/1RS doughs break down and soften during high‐speed mixing. The 1BL/1RS translocation has been shown to reduce cookie spread of soft wheat flours but has no deleterious effects on cake volume or texture. © 2002 Society of Chemical Industry     

EXTENSIONAL FLOW STUDIES ON WHEAT FLOUR DOUGHS WITH DIFFERENT PROTEIN CONTENT1

Uniaxial compression technique was used to relate the rheological behavior of dough to wheat quality for bread. Dough of nine flours of the cultivar Rayon, grown in three different regions of Sonora, Mexico, and with a protein content from 10% to 12.8%, were studied using the lubricated squeezing‐flow test connected to a texturometer. Wheat flour quality determinations were protein, moisture and ash content, dry gluten, falling number, and sedimentation volume. Traditional dough rheological evaluations were made with the farinograph and alveograph. The baking test was also done. The extensional viscosity was measured at three crosshead speeds (0.2, 0.5, and 1.0 mm/min). Extensional viscosity, measured at the lowest speed, significantly (P < 0.05) and negatively correlated with protein content (r = ‐0.63) and bread volume (r = ‐0.72). The rheological behavior of wheat doughs during lubricated uniaxial compression showed dependence on the strain rate as demonstrated by the patterns of the extensional viscosity curves.     

Prediction of mechanical dough development,water absorption and baking performance from farinograph parameters

Two systems for measuring flour water absorption (WA), the farinograph (FAR) and the Wheat Research Institute, 125 g mechanical dough development (MDD) standard bake test system, were compared using a representative sample of 20 commercial flours. A highly significant correlation (r = 0.93) was found which yielded the predictive equation: WA_MDD = 0.66 × WA_FAR + 181 The 95% prediction limits for 125 g MDD water absorptions from this equation were ± 15 g kg^?1. This degree of accuracy was largely due to excellent farinograph reproducibility. Other farinograph parameters (development time, stability and breakdown) were highly correlated with the work input required for 125 g mechanical dough development, but only development time was significantly correlated with the volume of loaves baked on the 125 g standard bake system. This lack of prediction of baking quality for the farinograph could partly be because it simulates bulk fermentation mixing, rather than the more intensive mixing of the mechanical dough development process used for the loaves in this experiment. However, the loaf volume range was diminished since sample preparation involved bulking flours by water absorption.     

小麦面团粘度影响因素研究进展

该文介绍国内外对小麦面团粘度影响因素研究进展;粘度是由面团粘结特性和内聚特性所共同决定一种特性,粘度过大会造成生产中断,且最终产品质量也会有所降低;麦谷蛋白及醇溶蛋白比例及结构、戊聚糖、1BL／1RS易位均对面团粘度产生影响。     

Impact of fat types on the rheological and textural properties of gluten-free oat dough and cookie

This study investigated the effect of six fats (margarine, butter, lard-LAR, refined palm oil-RPO, refined palm oil with stearin-RPOS, hydrogenated palm oil-HPO) with different solid fat content (SFC) on gluten-free oat dough and cookie properties. RPOS and HPO had the highest SFC. RPO dough was the softest, whereas HPO was the hardest one. Dough hardness was correlated with SFC (r = 0.87). Dough stickiness was positively correlated with dough hardness (r = 0.92). Dough hardness influenced the breaking force of the cookies (r = 0.79). HPO were the hardest cookies. Oscillatory test revealed that HPO dough was the stiffest as well as presented a higher rigidity compared to the other samples as showed by the creep tests. LAR cookies were the darkest, while HPO were the lightest. SFC of fats is the most important composition parameter which influences thermal, textural and rheological properties of the oat dough.     

多糖类亲水胶体对速冻油条面团特性及油条品质的影响

为了系统地研究7种常见的多糖类亲水胶体卡拉胶（KC）、魔芋胶（KGM）、海藻酸钠（SA）、阿拉伯胶（GA）、羟丙基甲基纤维素（HPMC）、黄原胶（XG）、瓜尔胶（GG）对速冻油条生坯制作中面团特性及速冻前后油条品质的影响，本研究通过OPLS-DA聚类分析、皮尔逊相关性等方法，对物性、理化、感官指标进行综合分析。结果表明：多糖类亲水胶体显著影响和面面团的硬度（r=0.62,P=0.020<0.05）与饧面面团的内聚性（r=-0.48,P=0.023<0.05），但二者之间无显著相关性（r=-0.27,P=0.22>0.05）；添加GA对饧面面团弹性影响最大（P<0.05）；多糖类亲水胶体显著影响油条酥脆性（r=-0.43,P=0.044<0.05）、内聚性（r=0.51,P=0.015<0.05）及口感（r=0.46,P=0.032<0.05）；油条各指标之间存在显著相关性（P<0.05）,KGM、HPMC、GG、GA、KC、XG、SA显著影响其外观及口感（P<0.05）；所考察指标之间相互影响显著（P<0.05），比容与组织结...     

ROLE OF OIL ON PHYSICAL PROPERTIES OF CORN MASA FLOURS AND SENSORY CHARACTERISTICS OF CORN TORTILLAS

This study was conducted to evaluate the effect of oil on physical properties of corn masa and sensory of tortillas. Oil from commercial and lab-made whole dry corn masa (DCM) was extracted with hexane. Both flours were reconstituted with 2, and 4% w/w of commercial corn oil, to have 50 and 100% oil reconstituted flours. These levels of reconstitution were to determine the impact of oil on dough properties and sensory characteristics of corn tortillas. The sensory analysis of both types of flours showed the same patterns. The absence of oil did not affect dough stickiness or tortilla reliability. But, low content of oil did adversely and significantly (p<0.05) affect the typical corn tortilla flavor. Presence of oil significantly improved tortilla firmness and chewiness.     

OBJECTIVE MEASUREMENTS OF THE CONSISTENCY OF CHAPATI DOUGH USING A RESEARCH WATER ABSORPTION METER

A Research Water Absorption Meter (RWAM) was adapted to measure the consistency of chapati doughs made from whole wheat flour (WWF). Doughs of optimum consistency were characterized by an extrusion time of 60 ± 5 s when extruded with an additional weight of 2 Kg, after resting the dough for 20 min. The RWAM consistency was Significantly correlated to the farinograph consistency ( r =+ 0.97), as well as to hardness ( r =+ 0.96) recorded on a General Foods Texturometer. The water required to prepare a chapati dough of this consistency can be determined from a semi-logarithmic plot of the extrusion time of doughs of varying water contents against the water added. Chapati water absorption can be determined by multiplying the farinograph water absorption measured at 500 B. U. by a factor of 0.85, or by adjusting the farinograph consistency to 460 ± 20 BU at a lever setting of 1:3 instead of 1:1. A multiple regression equation, derived for predicting chapati water absorption based on particle size, damaged starch, and protein content, accounted for 88% of the variation.     

QUALITY ATTRIBUTES OF CANADIAN HARD WHITE SPRING WHEAT

Quality characteristics of five pilot‐scale milled Canadian hard white spring wheats were compared to a No.1 grade commercial composite Canada Western Red Spring (1CWRS) wheat. One metric ton of samples was milled on the Canadian International Grains Institute pilot Buhler mill (Buhler AG, Uzwil, Switzerland) into straight‐grade (SG), 85% and whole wheat flours. At the SG extraction level, the white wheats with their lighter colored seed coats had improved milling yields (up to 2.6%) and lower ash (0.01–0.09%) than the 1CWRS control wheat. Majority of white wheat flours had higher protein contents than the 1CWRS control flours for all flour extractions. Based on dough rheological properties of the flours, three of the white wheats (Kanata, Snowbird and BW 275 ) were equal to or better than the red 1CWRS control for nearly all farinograph and mixograph parameters at all flour extractions other than farinograph absorption. Two of the white wheat lines (RL 4863 and RL 4858 ) had excessively weak and overly strong dough properties, respectively. Evaluation of pan bread, bagels and tortillas showed that white wheats generally produced end‐products that were comparable or superior to 1CWRS and that their most significantly positive quality compared to 1CWRS was their substantially lighter colored end‐products.     

Rheological and sensory characteristics of doughs and cookies based on wheat,soybean, chick pea and lupine flour

Levels of 5, 10 and 15% of legume flours i.e. soybean, lupine and chick pea were used to supplement cookie. The effect of this supplementation on the rheological properties of the resulting dough was investigated using farinograph and extensograph as objective methods for quality assessment of the final product. It was found that there was an increase in water absorption capacity, dough stability, arrival time, dough development time and mix tolerance index. Extensograph results indicated that dough resistance to extension, dough energy and proportional number were minimized with increasing the lupine flour in the formula, while it was not changed on dough extensibility. However, soy flour increased resistance to extension, proportional number and energy and diminished dough extensibility. At the same time supplementing wheat flour with chick peas decreased both dough resistance to extension and proportional number while it increased dough extensibility and energy. For sensory evaluation, it was found that using either until 5% soybean or 10% chick pea or 15% lupine flour could replace the wheat flour in cookies formula without adversely affecting baking performance or altering the physical characteristics of the end product.     

Comparative Effects of Various Sucrose-Fatty Acid Esters upon Bread and Cookies

Standardized bread and cookies were baked to test the effects of sucrose fatty-acid esters, ranging in HLB (hydrophyl-lipophyl-balance) from 1 to 15. Bread volume and tenderness and cookie spread were determined. Interactions between shortening and the esters were tested in bread, and between nonwheat flours and the esters in both bread and cookies. Bread volume was restored when up to 20% sorghum, millet and corn flours were added. Bread tenderness over a five-day period was also improved by use of the esters. The most practical emulsifier use levels ranged from 0.5—1.0%, depending upon emulsifier HLB.     

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.     

Physical and sensory characteristics of cookies prepared with flaxseed flour

BACKGROUND: Flaxseed has many health benefits and is considered a functional food ingredient. Flaxseed flour (0–18%) was used to partially replace wheat flour in cookies and its effects on the physical and sensory characteristics of the cookies were investigated. A correlation analysis was conducted between the instrumental and sensory data. RESULTS: The cookie dough stickiness significantly (P < 0.05) decreased in relation to higher percentages of flaxseed flour. The 18% flaxseed cookies had the firmest texture, darkest color and lowest water activity. The 18% flaxseed cookies had the greatest spread ratio. However, this resulted in cookies of unacceptable quality properties. In consumer acceptance tests, cookies made with 6% and 12% flaxseed flour had the highest rating among all sensory attributes, while the 18% flaxseed cookies had the lowest sensory scores. The flavor attribute was most highly correlated with the overall acceptability (r = 0.90). CONCLUSION: Results indicated that flaxseed flour can be incorporated in cookies as a partial replacement up to 12% of wheat flour without negatively affecting the physical and sensory quality. The correlation results suggest that the flaxseed flavor attributes best predict consumer preference for overall acceptability, though texture and color attributes also contribute. Copyright © 2012 Society of Chemical Industry     

蒸汽爆破甘薯渣粉对小麦粉粉质及饼干品质特性的影响

研究蒸汽爆破甘薯渣粉对小麦粉粉质及混合粉制作饼干品质特性的影响。将蒸汽爆破甘薯渣粉添加到小麦粉中,测定不同比例蒸汽爆破甘薯渣粉与小麦粉混合后的沉淀指数、糊化特性、粉质特性以及混合粉饼干质构性质。结果表明：小麦粉中添加不同量的蒸汽爆破甘薯渣粉后,小麦混合粉的沉淀指数、峰值黏度、低谷黏度、稀懈值、最终黏度和反弹值均降低;蒸汽爆破甘薯渣粉添加到小麦粉中,面筋蛋白被稀释,吸水能力随可溶性膳食纤维质量分数的增加而增加,而面团的形成时间和稳定时间缩短,弱化度升高,粉质质量指数降低;混合粉焙烤出的饼干质构特性发生变化。根据饼干的质构特性和感官评定结果,在低筋面粉中添加质量分数6%的蒸汽爆破甘薯渣粉时,混合粉制作的饼干品质最佳。     

UNIAXIAL COMPRESSIBILITY OF BLACKGRAM DOUGHS BLENDED WITH CEREAL FLOURS

The uniaxial compression characteristics of papad dough (moisture content 62%, dry basis), made from blackgram flour as well as after incorporation of different types of cereal (rice, sorghum and wheat) flours at different levels (20 and 40%), were determined. The stress-strain data can be interrelated by a power law type equation. The sensory attributes (stickiness, firmness, elasticity and ease of flattening/rolling) were correlated with the energy for compression, deformability modulus and apparent biaxial elongational viscosity. Inelastic doughs resulted from the blackgram dough; doughs with 20% rice or wheat blends were also inelastic but sorghum samples were elastic. The deformability modulus for sorghum doughs were extremely high. The blackgram dough as well as the wheat blended doughs were the easiest doughs to roll/flatten. Blended dough consisting of wheat flour (at 20 and 40% level) or rice flour up to 20% level was suitable for making cereal-blended papad doughs.     

EFFECT OF MINERAL FORTIFICATION ON RHEOLOGICAL PROPERTIES OF WHOLE WHEAT FLOUR

This study was aimed to evaluate the rheological changes that take place in the dough as a result of addition of elemental iron, ferric sodium ethylenediaminetetraacetate, zinc sulphate and zinc oxide in various combinations to whole wheat flour (WWF), packaged in polypropylene woven bags and tin boxes and stored for a period of 60 days under ambient and controlled conditions of temperature and relative humidity. Water absorption (WA) capacity, dough development time (DDT) and dough stability time (DS) of the fortified WWF were measured by farinographic method, and peak viscosity was assessed by viscographic analyses. WA capacity and DDT of flours increased during storage. Fortification significantly (P  <  0.05) affected WA, DDT, DS and viscographic characteristics of the flours. Packaging materials (P  <  0.05) influenced WA, DDT and DS, while storage condition had only affected viscographic properties of the flours.

PRACTICAL APPLICATIONS

The success of any fortification program depends on the stability of micronutrients and food to which they are added. Exposure of the fortificants to any of the physical and chemical factors including heat, moisture, air, or light and acid or alkaline environments during food processing, packaging, distribution or storage affects their stability. The rheological properties of dough made from fortified flours determine the quality of the fortified end product. Changes in rheological properties as a result of the incorporation of fortificants in the flour, its storage under variable conditions and length of time might have an effect on quality, cost and nutrition of the product.     

Wheat washing with ozonated water: effects on selected flour properties

Soft and hard wheat samples were washed using ozonated water (1.5 mg L⁻¹). Milling (rate of extraction), rheological (farinograph and extensograph characteristics), chemical (protein, falling number, sedimentation volume), colour (Hunter Laboratory values) and microbiological (total bacterial and yeast/moulds) properties of flours milled from the washed wheat were evaluated. Results indicated that washing with ozonated water did not significantly alter the chemical, physical or rheological properties of the flours from hard wheat samples. However, small but statistically significant ( P =0.05) differences were observed on extensograph values of flours milled from the soft wheat washed with ozonated water. A significant reduction ( P =0.05) in the total bacterial and yeast/mould counts was obtained after washing with ozonated water for both soft and hard wheat samples. Results suggest that ozonated water can be successfully used to wash hard wheat without affecting flour quality.     

Secalin蛋白检测及其与面团黏性关系的研究

用SDS—PAGE检测了70个小麦品种是否带有黑麦Secalin蛋白，并测试了它们的面团黏性，用PCR检测了部分品种是否含有1RS染色体片断，结果表明：70％的品种为1B／1R易位系；有54．3％的品种面团发黏；带有黑麦Secalin蛋白的品种约有72．5％面团发黏，而不带有黑麦Secalin蛋白的品种只有30％面团发黏；影响面团黏性的主要因素为来源于黑麦的Secalin蛋白；PCR扩增结果表明，在我国存在不带有Sec-1基因的1B／1R小片断易位系。     

Effect of β-Glucan Concentrate on the Water Uptake,Rheological and Textural Properties of Wheat Flour Dough

The effects of the addition of β-glucan concentrate (2.5–10 g/100 g flour) and water (58–70 mL/100 g flour) on the rheological and textural properties of wheat flour doughs were studied. Various empirical (farinograph, extensograph, dough inflation, and dough stickiness) and fundamental rheological tests (oscillatory and creep-recovery) were employed to investigate composite dough structure and an attempt was made to correlate the data obtained from different instrumental measurements. The water absorption increased with the addition of β-glucan concentrate into wheat flour. An increase in mixing time and stability were recorded upon addition of β-glucan concentrate (≤ 5 g/100 g flour), and the extensibility decreased at similar condition. The composite dough exhibited predominating solid-like behavior. The mechanical strength, dough stickiness, the peak dough inflation pressure decreased with increasing water content but those parameters increased with β-glucan concentrate incorporation within the studied concentration range. Creep-recovery tests for 5 g β-glucan concentrate/100 g flour doughs recorded less resistance to deformation with an increase in water level and data were well described by the Burger model. Thermal scanning of doughs revealed that the protein denaturation peak was significantly influenced by water content, and the values were ranged between 110 and 124°C. Significant relationships between empirical and fundamental rheological testing methods were found.