Optimization of Additive Combination for Improved Soy–Wheat Bread Quality

The protein content of ordinary white bread ranges from 8% to 9%. Specialty breads can be made with 13–16% protein by including soy protein. However, incorporating high levels of soy protein depresses loaf volume, gives poor crumb characteristics, and decreases acceptability. The objective of this study was to determine the influence of sodium stearoyl-2-lactylate (SSL), transglutaminase (TG), and xylanase (HE) on high-protein dough properties and bread quality and to improve dough handling and bread quality of soy–wheat bread by using an optimized additive combination. The influence of SSL, TG, and HE on soy–wheat dough and bread properties was modeled by response surface methodology. The negative effect of soy products on gluten network was confirmed. With regards to the additives tested and their combination, TG showed a major improving effect on dough rheological properties and crumb uniformity, whereas SSL and HE enhanced both dough and bread quality. The best formulation tested produced an increment of approximately 65% soy–wheat bread volume and a decrease of 79% and 71% crumb hardness and chewiness, respectively, compared with the standard formulation.     

硬脂酰乳酸钠对冷冻面团及其烘烤面包品质的影响

将硬脂酰乳酸钠(Sodium stearyl lactate,SSL)加入自制冷冻面团中,通过测定冷冻面团的流变学特性,以及冷冻面团烘烤面包的比容、质构特性和感官评分,研究SSL对冷冻面团及其烘烤面包品质的影响。结果显示,随着SSL添加量增加,冷冻面团弹性模量先升高后降低,损耗角正切tanδ先降低后升高,其中最优SSL添加量为0.20%;冷冻面团烘烤面包的硬度、咀嚼性先降低后升高,弹性、回复性、比容和感官评分先升高后降低,当SSL添加量为0.20%时,各指标达到各自的峰值,说明SSL改善了冷冻面团及其烘烤面包的品质。30 d冷冻储藏期内,加入SSL后,冷冻面团及其烘烤面包劣变幅度减小,说明SSL改善了其储藏特性。上述结果表明:加入SSL后,冷冻面团及其烘烤面包的品质及储藏特性得到改善,且最佳添加量为0.20%。     

麦胚对面包质量影响的研究

研究了全脂麦胚和脱脂麦胚对面团的流变学特性和面包质量的影响。结果表明,面团的筋力随麦胚量的增加而降低;脱脂麦胚比全脂麦胚的面包质量较好;脱脂麦胚的适宜加量为8％;麦胚能改善面包的皮色、风味和营养价值。     

氧化酶在全麦面包制作中的应用研究

将一种多酚氧化酶漆酶(Laccase,简称LAC)应用于全麦面包的制作,比较其与2种常用的氧化酶对面团的流变性质和面包品质的影响,旨在开发一种新型的烘焙用酶制剂。通过面团流变性质的测定及面包品质的综合评价研究氧化酶对面团和面包质量的影响,结果表明LAC可提高普通面团和全麦面团的黏弹性,对全麦面团的作用更强。全麦面包中加入LOX和LAC能显著增加全麦面包的比容,并以LAC提高比容最为明显。LAC对全麦面包质构的改善作用最明显,且能改善全麦面包的风味。质构测定结果表明LAC对全麦面包质构的改善作用最强。LAC可明显延长面包的老化时间。     

脱脂大豆粉对小麦粉及馒头品质影响研究

将脱脂大豆粉添加到小麦粉中,研究其对小麦粉理化特性和馒头制作品质的影响。研究结果表明,在小麦粉中添加低于2%的脱脂大豆粉时,可以明显地改善小麦粉的品质,具体体现在可以增加面粉的白度,增加面团的吸水量、稳定时间以及拉伸曲线面积和拉伸比数,还可以改善馒头的品质;当在小麦粉中添加高于2%的脱脂大豆粉时,其对面粉的品质具有不好的影响,具体体现在降低小麦粉的白度以及面团的筋力,对馒头的品质也具有不良的影响,表现为馒头体积变小,颜色发暗。     

Antistaling Additives, Flour Type and Sourdough Process Effects on Functionality of Wheat Doughs

Antistaling additives—distilled monoglycerides (MGL), diacetyl tartaric ester of monodiglycerides (DATEM), sodium stearoyl lactylate (SSL), carboxymethylcellulose (CMC), hydroxypropylmethylcellulose (HPMC) and fungal α-amylase—were studied for effects on rheological and fer- mentative properties of white/whole wheat bread doughs, made following straight/sour dough processes. A fractionated factorial design (L³²) was used to evaluate single additive effects and interactions. Single addition of DATEM, followed by SSL, α-amylase and hydrocolloids improved oven rise and final volume. In presence of DATEM, synergistic (MGL) and antagonistic (SSL) effects of additional emulsifiers were found on gassing power. SSL was the only effective conditioner for enhancement of mixing properties. Dough plasticity was negatively affected by MGL addition and by CMC/HPMC in white/whole flours respectively. Some combinations resulted in detrimental dough handling properties.     

品质改良剂对复合杂粮面包粉流变学特性的影响

以营养优化后的复配杂粮面包粉为原料,选择谷朊粉、硬脂酰乳酸钠（sodium stearoyl lactylate,SSL）、黄原胶及瓜尔豆胶为品质改良剂,通过单因素试验研究4 种品质改良剂对杂粮面包粉流变学特性的影响,在此基础上通过响应面分析试验,以面团综合得分为响应值,得出复合改良剂的最佳配方为：1 000 g杂粮面包粉（杂粮粉占比34%）为基重,谷朊粉3.77%、SSL 0.35%、黄原胶1.08%、瓜尔豆胶0.35%。各因素对杂粮面包粉综合评分的影响大小为：黄原胶添加量＞谷朊粉添加量＞瓜尔豆胶添加量＞SSL添加量。添加复合改良剂后杂粮面包粉的稳定时间由4.7 min上升到14.2 min,形成时间由3.9 min上升到了13.3 min,粉质指数从56上升到192。复配杂粮面包粉流变学特性有很大程度改善,达到制作杂粮面包的粉质要求。     

米糠可溶性膳食纤维对馒头抗老化特性的影响

为了提高小麦面制品的抗老化能力,本研究将脱脂米糠可溶性膳食纤维以不同的比例加入小麦淀粉,经面团发酵后制成馒头,分析该馒头的品质变化及抗老化效果.结果 表明,米糠膳食纤维的加入能够延缓馒头的老化.当添加量为5％时,面团的膨胀体积最大,与对照组相比馒头的硬化速率降低了35％,且在4℃下贮藏5d后,硬度、咀嚼度分别降低了33...     

Baking Studies with Winged Bean (Psophocarpus tetragonolobus L.DC) Flour-Wheat Flour Blends

Physical, rheological and baking properties of winged bean-wheat composite flours were studied and the acceptability of the bread was evaluated by sensory tests. The sponge-dough method (SPD) gave bread with significantly greater specific loaf volume (P<0.05) than the straight-dough method (STD). Incorporation of 1% sodium stearoyl 2-lactylate (SSL) significantly improved (P<0.05) the specific loaf volume at all concentrations of winged bean full-fat flour (WBFF) tested, except for 15 and 20% substitution, for both STD and SPD methods. Using the STD method, 5% to 8% substitution of WBFF without SSL and 10% substitution with SSL gave acceptable breads. Using the SPD method, WBFF substitution at 10% without SSL and 12% with SSL gave acceptable breads.     

三种甘油酯对冷冻面团及其面包品质的对比分析

本文通过核磁共振测定冷冻面团及其面包的水分迁移情况,流变仪测定冻藏过程中冷冻面团的流变学特性,质构仪和扫描仪分析面包的品质,研究三种甘油酯:乙酰化单、双甘油脂肪酸酯(ACETEM),双乙酰酒石酸单双甘油酯(DATEM)和六聚甘油单油酸酯,对冷冻面团及其面包品质的影响。结果表明:在冻藏过程中,三种甘油酯对冷冻面团及其面包的品质均有改善。与对照组相比,冻藏前三种甘油酯增加了面团及其面包的结合水比例,分别是面团增加了4.21%、7.02%、11.23%和面包增加了0.27%、4.67%、16.00%。而冻藏后,三种甘油酯降低了冷冻面团及其面包的水分迁移。在冻藏期间,冷冻面团的粘弹性降低,它们的损耗角正切值(tanδ)增加,发酵后对照组面团的tanδ增加了11.90%,添加了0.5%ACETEM面团的tanδ仅增加了4.76%。冻藏60d后,含0.5%ACETEM的面包比容为3.29m L/g,比对照组增大了23.50%;面包硬度为2298.92g,比对照组柔软19.18%。因此,添加了0.5%ACETEM的改善效果最好。     

Effect of surfactant gels on dough rheological characteristics and quality of bread

Sodium stearoyl-2-lactylate (SSL), diacetyl tartaric acid esters of monoglyceride (DATEM), glycerol monostearate (GMS), and distilled glycerol monostearate (DGMS) surfactant gels were made with water and varying shortening contents. The effect of these gels on dough rheological characteristics and quality of bread was investigated. Overall, the surfactant gels improved the farinograph and extensograph characteristics of wheat flour, but the improvement reduced to some extent with the presence of shortening in the gels. Alveograph data indicated that dough properties improved with the addition of surfactant gels. Shortening in gels showed varying influence on the dough alveograph properties of wheat flour. The results indicated that the surfactant gels changed the rapid visco analyzer characteristics of wheat flour, and the presence of shortening in gels further altered the characteristics. All surfactant gels improved the volume, specific volume, texture, and overall quality scores of bread, but the improvement varied for different surfactants. By increasing the addition of shortening in gels, though the quality characteristics further improved, the response to surfactants reduced by increasing shortening content.     

Effect of Surfactant Gels on Dough Rheological Characteristics and Quality of Bread

Sodium stearoyl-2-lactylate (SSL), diacetyl tartaric acid esters of monoglyceride (DATEM), glycerol monostearate (GMS), and distilled glycerol monostearate (DGMS) surfactant gels were made with water and varying shortening contents. The effect of these gels on dough rheological characteristics and quality of bread was investigated. Overall, the surfactant gels improved the farinograph and extensograph characteristics of wheat flour, but the improvement reduced to some extent with the presence of shortening in the gels. Alveograph data indicated that dough properties improved with the addition of surfactant gels. Shortening in gels showed varying influence on the dough alveograph properties of wheat flour. The results indicated that the surfactant gels changed the rapid visco analyzer characteristics of wheat flour, and the presence of shortening in gels further altered the characteristics. All surfactant gels improved the volume, specific volume, texture, and overall quality scores of bread, but the improvement varied for different surfactants. By increasing the addition of shortening in gels, though the quality characteristics further improved, the response to surfactants reduced by increasing shortening content.     

Significance of viscosity profile of pasted and gelled formulated wheat doughs on bread staling

Pasting profile during cooking and cooling of straight/soured started bread doughs formulated with non fat-sodium carboxymethylcellulose (CMC), hydroxypropylmethylcellulose (HPMC), fungal α-amylase and fat-monoglycerides (MGL), diacetyl tartaric acid ester of mono-diglycerides and sodium stearoyl lactylate (SSL)-additives was recorded in the Brabender (BVA) visco-amylograph and Newport rapid viscoanalyser (RVA). Rheological results were correlated with bread staling kinetics during storage. Bread dough viscosity characteristics, derived from the RVA pasting profile during cooking and cooling, highly correlate with bread staling kinetic parameters. This is particularly so in the cases of peak viscosity, pasting temperature, and setback during cooling that can be considered as valuable predictors, at a dough level, of bread firming behaviour during storage. Individual and/or binary addition of surfactants to bread dough, particularly MGL and SSL, positively influence the level of the pasting parameters associated with a significant delay in bread firming. Individual additions of methylcellulose derivatives, mainly CMC, induce in general a deleterious effect on dough viscosity. Moreover, the simultaneous presence of CMC and HPMC results in a significant improvement of dough rheology during cooling. Binary mixtures SSL/CMC and MGL/CMC are not recommended from the viscoelastic point of view, due to antagonistic effects of the pair gum/surfactant that nullify the benefits of individual emulsifiers.     

乳化剂改善无麸质面包焙烤特性的研究

研究了乳化剂对无麸质面包(米粉、红薯淀粉)比容、硬度、色泽及感官品质的影响。结果表明,添加硬脂酰乳酸钠、蔗糖脂肪酸酯、大豆卵磷脂、分子蒸馏单甘酯可改善无麸质面包的品质,面包比容增大,结构松软,气孔更加均匀,硬度降低,色泽改善,感官品质提高。综合来看,添加0.5g/100g的分子蒸馏单甘酯无麸质面包品质改善最为明显,比容增加16.9%,硬度降低46.9%(24h),面包色泽明显改善,感官品质最好。     

小麦胚芽在面包中应用的研究

本文初步探讨了小麦胚芽在二次发酵法制作面包中的应用,研究了不同小麦胚芽预处理条件、添加量和主面团加水量、面包改良剂使用量对面包体积比及面包质量评分的影响。结果表明:就面包体积而言,面包中添加麦胚片优于添加麦胚粉;烘烤、焙炒、脱脂处理的小麦胚芽均可应用于面包中,但添加烘烤麦胚的面包品质最佳,其次是脱脂麦胚,焙炒处理的麦胚面包质量较差,最佳小麦胚芽添加量、主面团加水量和面包改良剂使用量分别是6%、20%和0.6%。     

Wheat Germ Lipoxygenase: Its Effect on Dough Rheology,Microstructure, and Bread Making Quality

Extracted lipoxygenase from defatted wheat germ of commercial bread wheat along with raw and defatted germ were used to study their effect on rheological characteristics of wheat flour dough and bread making quality. The addition of 500 U and 1000 U of lipoxygenase increased the water absorption from 59.5 to 62.3 and 66.7%, respectively. The dough stability increased to 10.5 min, whereas mixing tolerance index values marginally decreased, and the addition of raw or defatted germ did not affect the mixing profile of the wheat flour dough. Breads with lipoxygenase were softer with a lower firmness value of 546 g when compared to the control (594 g) and had brighter crumb as seen in the reduction in ΔE values from 22.34 (control) to 19.04. The addition of gluten along with the lipoxygenase showed a synergistic effect. The specific volume of breads increased to 3.95 cc/g and the firmness values decreased to 538 g. Scanning electron micrographs at different stages of bread processing have shown improvement in the gluten network.     

Effects of Defatted Jack Bean Flour and Jack Bean Protein Concentrate on Physicochemical and Sensory Properties of Bread

This study evaluated the effects of substituting wheat flour with defatted Jack bean flour and Jack bean protein concentrate on bread quality. Jack bean flour milled from the seed nibs was defatted with n-hexane and part of the defatted flour (DJF) extracted in acid medium (pH; 4.5) for protein concentrate (JPC). Both the DJF and JPC were analysed for nutrient composition, and then used to fortify bread. Five bread samples with 0%, 10% and 20% of DJF or JPC were prepared using straight dough procedure, and then analysed for quality characteristics. The DJF and JPC had 28.8% and 49.47% protein, 46.44% and 30.22% carbohydrate, 0.61% and 1.00% crude fibre respectively; and were rich in Ca, Fe, Zn and P. Both DJF and JPC improved quality of bread but JPC conferred better quality. The 20% DJF and JPC respectively improved protein content of bread from 9.45% to 10. 97% and 11.16%, crude fibre from 2.39% to 5.20% and 5.32%, fat from 2.35% to 7.00% and 6.55%, and ash content from 1.35% to 2.05% and 2.10% but decreased carbohydrate content from 72.12% to 50.45% and 50.39% in the bread samples. All the fortified bread samples had acceptable crumb colour, crumb texture, flavour and loaf volume significantly comparable (p > 0.05) to those of 100% wheat bread. Thus, defatted Jack bean flour and Jack bean protein concentrate is recommended for use in fortifying bread for higher quality.     

Incorporating L-Ascorbyl 6-Palmitate in Bread and Its Shortening-Sparing and Anti-Firming Effects

L-Ascorbyl 6-palmitate (AP) was conveniently incorporated in bread dough by gently premixing AP in vegetable oil or shortening, adding the premix with the remaining ingredients and mixing the dough at conventional speeds. Alternatively, high-speed mixing of AP with formula flour or water also gave fully functional AP in bread doughs as evidenced by complete shortening replacement at 0.38% AP (based on flour weight) and by the absence of dark specks on the crust of bread. Compared to a mixture of 0.38% AP and 3% shortening or a mixture of 0.5% monodiglycerides and 3% shortening, AP alone at 0.38% in bread gave softer crumb after 1 to 5 days storage at 25°C. Sodium stearoyl 2-lactylate (SSL) at 0.38% gave the same softening effect as AP. In no-shortening loaves, 0.38% AP gave better grain than 0.75% L-ascorbyl 6-octanoate or 0.50% L-ascorbyl 6-dodecanoate.     

Effect of flour blending on functional, baking and organoleptic characteristics of bread

Soybean (full‐fat and defatted) and barley flours were incorporated into wheat flour at 5, 10, 15 and 20% substitution levels. The gluten content, sedimentation value and water absorption capacity of the flour blends and the mixing time of the dough decreased with increase in the level of soybean and barley flour separately and in combinations. Protein and glutelin contents increased significantly on blending of soyflour (full‐fat and defatted) to bread wheat flour. The breads prepared from the blends also varied in their loaf weight, loaf volume and sensory characteristics. The bread volume decreased with increasing amount of non‐wheat flour substitution. The crumb colour changed from creamish white to dull brown and a gradual hardening of crumb texture was observed as the addition of soybean (full‐fat and defatted) and barley flours increased. At the higher levels, the acceptability declined because of the compact texture of the crumb and the strong flavour of the product. The addition of 10% of soyflour (full‐fat and defatted) or 15% of barley flour, full‐fat soy + barley or defatted soy + barley flour to bread flour produced acceptable bread.     

脱脂活性豆粉对面粉品质的影响

通过在面粉中添加一定比例的脱脂活性豆粉,研究了其对面粉流变学性质、快速粘度性质及馒头品质影响。粉质试验表明,脱脂活性豆粉可使面团的校正吸水率提高,稳定时间提高(除1.0%略低于空白外),形成时间缩短,粉质指数提高,弱化度降低;快速粘度特性结果表明,脱脂活性豆粉可使面粉峰值粘度、低谷粘度、崩解值和最终粘度降低,糊化温度(除2.5%)提高;馒头实验表明,脱脂活性豆粉可以提高馒头表面白度,增加成品质量和体积。