Extractability and Chromatographic Characterization of Wheat (Triticum aestivum L.) Bran Protein

About 70% of the protein for human consumption is derived from plants, with cereals as the most important source. Wheat bran protein has a more balanced amino acid profile than that of flour. We here for the first time report the amino acid, size exclusion, and SDS‐PAGE profiles of bran Osborne protein fractions (OPFs). Moreover, we also investigated how OPFs are affected when physical barriers which entrap proteins in bran tissues are removed. Albumin/globulin is the most abundant OPF. It is richer in lysine and asparagine/aspartic acid than other OPF. Most bran albumin/globulin proteins have a molecular weight (MW) lower than 30 k and their chromatographic profiles differ from those of flour. The prolamin has high levels of proline and glutamine/glutamic acid. It is rich in proteins with a MW of 30 to 45 k and about 66 k reflecting contamination with gliadin from endosperm. The glutelin has high levels of glycine, proline, and glutamine/glutamic acid. Its protein is of intermediate and high MW with little protein with MW lower than 30 k. The high (MWs from 80 to 120 k) and low (MW around 45 k) MW glutenin subunits of flour are also present in bran. The glutelin of wheat endosperm is named glutenin. Ball milling releases albumin/globulin and glutelin but not prolamin. Not all glutelin was endosperm glutenin as a substantial part was entrapped in the aleurone cells.     

小麦麸皮的品质改良及含麸皮面包焙烤品质的研究

本研究采用微波辐照联合复合酶法对小麦麸皮进行改良,将改良后的小麦麸皮添加至高筋粉中得到不同小麦麸皮含量的含麸皮面粉并制作含麸皮面包。结果表明:改良后小麦麸皮中脂肪酶残余酶活和脂肪氧化酶残余酶活降低至0和10.34%、粗纤维含量降低至3.21%、还原糖含量上升至3.79 g/100 g。与改良前的全麦面包相比,改良后的全麦面包组织结构得以改善、全麦面包储藏7d后吸热焓值降低了14.70%、全麦面包中酮基、羰基、醛基含量增多。改良后的全麦面包比容增加了26.40%、硬度降低了32.90%、弹性增大了6.90%。随着改良麸皮添加量的增加,含麸皮面包组织结构变得粗糙多孔,含麸皮面包吸热焓值逐渐降低,酮基、羰基、醛基含量增多,含麸皮面包芯亮度逐渐变暗、比容逐渐降低、硬度逐渐增加、弹性逐渐减小、感官品质降低。与未稳定化麸皮含量16%的全麦面包相比,稳定化全麦面包的稳定性、贮藏性和质构得到明显提高。     

麦麸膳食纤维对面团流变学特性及馒头品质的影响

研究了麦麸膳食纤维的加工技术并制备了微细化活性麦麸膳食纤维;分别添加5％、8％、10％、12％和15％的麦麸膳食纤维素到面粉并调制成面团,记录并测定其粉质特性参数与拉伸特性参数。结果表明：麦麸膳食纤维的添加使面团的吸水率增大、形成时间与稳定时间显著延长、弱化度下降,面团的粉质特性得到明显改善,但其面团的弹性逐渐下降;麦麸膳食纤维的添加使面团的抗拉伸阻力和拉力比数增大．而使面团拉伸能量和延伸性变小。按传统工艺技术制备了不同麦麸膳食纤维添加量的馒头样品,并进行了感官评价．麦麸膳食纤维的添加使馒头的体积及馒头感官指标评价得分均呈下降的趋势,当其添加量为8％时,馒头的总体品质评价得分高于80％。是可以为消费者所接受。     

添加改性麸皮对含麸皮面包结构及消化特性的影响

采用酶解-高压湿热处理对小麦麸皮进行改良,将改良后的小麦麸皮回添至高筋粉中获得不同麸皮含量的面粉,制作含麸皮面包,研究改良麸皮添加量对含麸皮面包的结构及消化特性的影响规律.结果 表明:改良后的小麦麸皮中脂肪酶残余酶活降至0,不溶性膳食纤维含量从37.38％降低至15.64％,持水力升高了41.26％.与改良前的含麸皮面...     

麦麸超微粉对面团特性及制品品质的影响

对超微粉碎麦麸粉面团的流变学特性进行研究,分别将超微粉碎麦麸(添加质量分数分别为0%、5%、10%、15%、20%)添加到面粉中并调制成面团,测定并记录其粉质特性和拉伸特性等。结果表明：麦麸超微粉的添加会使面粉的吸水率增大,面团形成时间、弱化度均有所增加,面团的稳定时间呈下降趋势;从粉质特性总体来看,超微麦麸粉的添加能改善面粉的粉质特性。在麦麸超微粉添加量在10% 时,麦麸超微粉馒头样品模糊综合评价结果为良好,其色泽、气味、组织结构、口感都可以被人接受。     

发酵麸皮混合物对面包品质的影响

为改善麸皮面包的品质,增加麸皮的利用率,本实验应用甜酒曲联合酵母发酵麸皮、黄豆和花生的混合物,得到发酵麸皮混合物。以面粉+发酵麸皮混合物总量为100 g(面粉90 g、发酵麸皮混合物10 g)计,制备发酵麸皮混合物面包(简称发酵麸皮面包),以普通面包、麸皮面包及添加黄豆、花生混合物的非麸皮添加物面包为对照,对这几种面包的品质、风味物质及抗氧化活性进行分析。结果表明:黄豆、花生的添加能够起到提升面包风味的作用;发酵麸皮混合物的添加可以改善麸皮面包的品质,其感官评分、弹性、硬度和色差L、b值极显著优于麸皮面包(P0.01),而与普通面包比较没有显著差异(P0.05);与3种对照面包样品比较,发酵麸皮面包的醇类、酯类和醛类等风味成分种类较多,且分布均匀,而且还检测出其特有的风味物质,分别为吡嗪类、呋喃类、乙基酯类;发酵麸皮面包的多酚、黄酮含量以及抗氧化活性指标也均最高。综上,发酵麸皮混合物能够改善麸皮面包的品质,并提高面包的抗氧化活性。     

Quality of bread made from ozonated wheat (Triticum aestivum L.) flour

BACKGROUND: Ozone gas could be used as a fumigant during grain and flour storage. Experiments were conducted to determine the effects of exposure to ozone and the effects of blending ozone‐treated flour with control flour on flour functionality and bread‐making quality. RESULTS: Ozone treatment oxidized lipids, increased brightness and reduced the yellow hue of flour, and increased peak viscosity and setback viscosity of flour. Bread made from flour treated with ozone at 1500 mg kg^?1 for 4.5 min and bread made from flour blended with 100 g kg^?1 ozonated flour had good crust color and a whiter crumb and had more crumb cells, which resulted in a greater specific volume of the bread when compared with control flour. Flour functionality declined as ozone exposure increased beyond 9 min and as the concentration of ozonated flour increased beyond 200 g kg^?1. CONCLUSION: Bread made from flour exposed to ozone for 4.5 min or flour that contained 100 g kg^?1 fully ozonated flour had greater specific loaf volume and whiter crumb compared to bread made with control flour. Exposure of flour to ozone for longer times (9–45 min) and higher blends (200–1000 g kg^?1) deteriorated quality of bread. Copyright © 2011 Society of Chemical Industry     

发酵麦麸对面包膳食纤维组成及烘焙特性的影响

采用马克斯克鲁维酵母发酵麦麸制得富含天然酶的功能配料,分析麦麸发酵过程中纤维素酶活力变化,比较制作的麦麸面包(B₁)、发酵麦麸面包(B₂)、木聚糖酶麦麸面包(B₃)和复合麦麸面包(B₄)的膳食纤维组成及烘焙特性的差异。结果表明:马克斯克鲁维酵母具有较强的胞外β-葡萄糖苷酶生产能力,其酶活为6.98 U/g;在48 h麦麸发酵过程中,外切葡聚糖酶和β-葡萄糖苷酶的酶活不断提高,其酶活分别增加至6.06和21.70 U/g,不溶性膳食纤维(IDF)也持续降解至38.30 g/100 g。面团搅拌、醒发过程中,还原糖含量不断增加,且添加发酵麦麸的面包效果最明显。相比未发酵麦麸面包,添加发酵麦麸的面包体积、弹性及持水力都显著提升(p<0.05),气孔结构更加细腻。制作的4种面包中总膳食纤维(TDF)和阿拉伯木聚糖(AX)含量没有显著差异,而添加发酵麦麸及木聚糖酶都能促进面包中IDF和AX溶解。     

脱脂糯小米米糠粉对面团流变学性质及馒头品质的影响

对比两种不同目数脱脂糯小米米糠粉（简称米糠粉）对面团流变学性质的影响;采用感官评价和质构分析相结合评价其对馒头品质的影响,确定其最适添加量。结果表明：两种粒度米糠粉在添加量为6%（质量分数,下同）以下时,对面团的粉质特性均有一定的改良作用。两种米糠粉的添加对面团的拉伸特性都有一定的恶化作用,但100～200 目米糠粉添加量为4%～6%和过400 目米糠粉添加量为6%～8%时,面团的拉伸特性恶化不明显。随着100～200 目米糠粉添加量的增加,馒头的白度值逐渐减小;添加量为4%～6%时馒头的硬度、弹性、咀嚼性和回复性都较好,且感官评价得分较高。过400 目米糠粉的添加对馒头的白度值影响相对较小,其添加量小于6%时馒头质构性质较好,且感官评价得分高于100～200 目米糠粉。综上所述,添加适量的米糠粉可以在一定程度上延缓馒头老化,100～200 目米糠粉的添加量应控制在4%～6%,过400 目米糠粉添加量应控制在6%～8%。     

Effect of Wheat Bran Particle Size on Dough Rheological Properties

Commercial hard red spring, hard red winter, soft white and durum wheat brans were used to investigate the effect of wheat bran particle size on the rheological properties of doughs. Wheat brans were first coarsely ground and passed through a bran finisher to remove additional endosperm and aleurone layers. These processes increased total dietary fibre content and decreased starch content of the wheat bran samples. Three particle size distributions, for each wheat bran class, were obtained by further grinding (not by sifting) of the bran samples by different experimental mills. Coarse bran can retain significantly more water than medium or fine bran as measured by a centrifuge method, but bran particle size had no significant effect on dough water absorption. Addition of wheat bran into bread dough systems increased dough water absorption rate, reduced mixing time and decreased dough mixing tolerance as measured by farinograph. Fine particle size wheat bran decreased dough mixing tolerance and reduced mixing time compared to coarse bran. Dough containing fine particle size bran exhibited more strength than dough containing coarse bran after a 180-min rest period as measured by the extensigraph. © 1997 SCI.     

冬小麦麸皮抗冻蛋白的筛选及其分离纯化

抗冻蛋白是一种可以非依数性降低体系冰点的蛋白质,在生命体内具有非常重要的生理作用.从多种谷物中筛选,发现冬小麦麸皮粗蛋白显示出抗冻活性.进一步依次采用硫酸铵沉淀、离子色谱、凝胶色谱以及HPLC等步骤将其分离纯化,最终获得色谱纯的冬小麦麸皮抗冻蛋白.该蛋白总纯化倍数为357倍,产率为1.60%.电泳分析确定该抗冻蛋白由单一亚基组成,分子质量为13 860 u.     

小麦麸皮和大豆粉对面包营养成分及风味的影响

分别用小麦麸皮和全脂大豆粉替代小麦粉进行面包制作,研究小麦麸皮和全脂大豆粉的添加对面包中蛋白质、各种氨基酸(AA)等营养成分,风味物质组成及含量的影响,结果表明:在小麦粉中添加小麦麸皮和全脂大豆粉,引起面包中的蛋白质含量、粗纤维含量以及部分氨基酸水平明显增加,达到了营养强化的作用;小麦麸皮面包中共检出风味物质87种,总含量减少了11.36%,但主要香气物质的增加使麸皮面包更具浓郁的香味;全脂大豆粉面包中共检出风味物质89种,总含量增加了9.89%,且几乎所有影响风味的物质含量都有不同程度的增加。     

Discrimination of Volatiles of Refined and Whole Wheat Bread Containing Red and White Wheat Bran Using an Electronic Nose

Abstract: The principal objective of this study was to evaluate the capability of electronic (E) nose technology to discriminate refined and whole wheat bread made with white or red wheat bran according to their headspace volatiles. Whole wheat flour was formulated with a common refined flour from hard red spring wheat, blended at the 15% replacement level with bran milled from representative samples of one hard red and 2 hard white wheats. A commercial formula was used for breadmaking. Results varied according to the nature of the sample, that is, crust, crumb, or whole slices. Bread crust and crumb were completely discriminated. Crumb of whole wheat bread made with red bran was distinct from other bread types. When misclassified, whole wheat bread crumb with white bran was almost invariably identified as refined flour bread crumb. Using crust as the basis for comparisons, the largest difference in volatiles was between refined flour bread and whole wheat bread as a group. When refined flour bread crust was misclassified, samples tended to be confused with whole white wheat crust. Samples prepared from whole bread slices were poorly discriminated in general. E‐nose results indicated that whole wheat bread formulated with white bran was more similar in volatile makeup to refined flour bread compared to whole wheat bread made with red bran. The E‐nose appears to be very capable to accommodate differentiation of bread volatiles whose composition varies due to differences in flour or bran type. Practical Application: Consumer preference of bread made using refined flour in contrast to whole wheat flour is partly due to the different aroma of whole wheat bread. This study used an electronic nose to analyze bread volatiles, and showed that whole wheat bread incorporating white bran was different from counterpart bread made using red bran, and was closer in volatile makeup to “white” bread made without bran. Commercial millers and bakers can take advantage of these results to formulate whole wheat flour with brans of preferred type in order to foster increased consumption of whole wheat products which confer many favorable health benefits.     

固态发酵对麸皮抗氧化特性及全麦面包感官品质的提升作用

用植物乳杆菌LB-1和酿酒酵母对小麦麸皮进行固态发酵,利用发酵麸皮重组全麦粉制备全麦面包,并对固态发酵麸皮的抗氧化特性及全麦面包的色泽、组织结构、风味、口感等感官品质进行分析.结果表明:经过乳酸菌LB-1与酵母菌协同发酵36?h后,麸皮的总游离氨基酸、可溶性蛋白、可溶性多酚和可溶性阿拉伯木聚糖分别增加了0.44、0.8...     

特异性亲和吸附法纯化冬小麦麸皮抗冻蛋白

抗冻蛋白是一种可以非依数性降低体系冰点的蛋白质,在生命体内具有非常重要的生理作用,广泛地应用于食品、医学和生物技术等领域.首先通过热重分析仪法和分配系数法研究证明冬小麦麸皮抗冻蛋白(TaAFP)具有较强的亲水性和亲冰性,进一步使用特异性亲和吸附法对其纯化,产率1.64%,获得电泳纯TaAFP.纯化过程中充分利用其自身较强的亲水和亲冰的特性.该方法具有步骤少、耗时较短等优点,比传统的色谱方法更加快捷高效,但是对纯化过程的控制要求严格.     

Bread Quality of Wheat Flour by Near-Infrared Spectrophotometry: Feasibility of Modeling

Commercial bakeries need a means to measure the dough-handling and bread-making functionalitv of wheat flour during processing. The feasibility of using near-infrared (NIR) reflectance spectrophotometry for such measurement was examined. Flour from hard red spring and hard red winter wheat were tested for: water absorption, dough mixing time, dough mixing tolerance, loaf height, internal grain appearance, and overall bake score. The ability of NIR to measure protein level, and/ or starch damage, as well as positive relationships between the two and water absorption, probably made it successful for modeling water absorption. Models for the remaining five indices were less accurate due to the complexity of interactions between protein, starch, and lipids, and inadequate instrument sensitivity.     

发酵麦麸及其面包面团中阿拉伯木聚糖溶解性与酚酸释放研究

将发酵麦麸作为功能配料用于高膳食纤维面包面团制作,采用化学分析、高效液相色谱及离子色谱法分析麦麸发酵、面包制作过程及面包中阿拉伯木聚糖溶解性和酚类化合物释放。结果表明：随着发酵时间延长,麦麸中水溶性阿拉伯木聚糖、游离酚及阿魏酸含量逐渐增加。发酵处理后,麦麸中游离阿拉伯糖、葡萄糖和果糖含量增加,水溶性阿拉伯木聚糖含量显著提高,分支度显著下降（P＜0.05）。面包搅拌、醒发及烘焙过程中,阿拉伯木聚糖不断溶解,酚类化合物持续释放;富含发酵麦麸的面包中水溶性阿拉伯木聚糖含量及分支度更高。模拟肠、胃消化后,富含发酵麦麸的面包中游离酚和阿魏酸含量更高,且吸收效果好。此外,发酵麦麸显著提高了面包的抗氧化活性。     

稳定化米糠在面包中的应用研究

研究添加稳定化米糠对面团粉质特性和面包品质的影响。添加5％米糠的面包品质与纯面粉面包非常接近。添加10％～15％米糠会影响面包体积、包心色泽和口感。制作面包时将米糠用油脂覆盖可消除米糠气味和苦味。