Influence of puroindoline alleles on milling performance and qualities of Chinese noodles,steamed bread and pan bread in spring wheats

Two trials with a total of 75 spring bread wheat cultivars and advanced lines, were used to evaluate single kernel characterization system hardness, puroindoline alleles, milling yield, flour ash content, flour colour, and end-use qualities for Chinese noodles, steamed bread and pan bread. The results indicated that all International Maize and Wheat Improvement Center hard wheat lines surveyed were Pina-D1b genotype, whereas Pinb-D1b was the most common allele in the remaining cultivars. Genotypes with Pinb-D1b possess significantly lower flour ash content and higher milling yield than those of genotypes with Pina-D1b. For steamed bread, mean scores for loaf volume, crumb colour, width, structure and total score of Pinb-D1b genotypes were significantly higher than those of genotypes with Pina-D1b and wild type. For Chinese fresh white noodles, means for noodle a*, colour score, viscoelasticity and total score with Pinb-D1b were significantly higher than those of Pina-D1b and wild type. Means of loaf volume, texture and total score for Pinb-D1b genotypes were significantly higher than those of Pina-D1b genotypes. This study further illustrated the superiority of the Pinb-D1b allele on milling and processing qualities for various end products and provides useful information for wheat quality improvement.     

Effect of inulin with different degree of polymerization on plain wheat dough rheology and the quality of steamed bread

The aim of this study was to evaluate the effect of different polymerization degree of inulin on plain wheat dough rheology and quality of steamed bread. It was found the water absorption of dough decreased with the increasing of short-chain (FS) and natural inulin (FI) and increased with the increasing of long-chain inulin (FXL) higher than 7.5%. Three kinds of inulin all increased the development time, stability and farinograph quality number and decreased softening degree of the dough. When proof time was less than 90min, the extensibility increased with the substitution of 5% of FS, 5% of FI and 2.5% of FXL. The resistance to extension, ratio number of resistance to extensibility and energy all increased with the increasing of FS and FI as well as the time. While the energy increased with FXL substation at 45min and dropped thereafter, regardless of the concentration. The addition of inulin all enhanced the brightness, specific volume and hardness of steamed bread and decreased the water content, vaporization enthalpy, springiness, recovery, and cohesiveness. During the storage, inulin reduced the change rates of relative hardness, recovery, and cohesiveness and increased the change rate of relative enthalpy, which restrained the staling rate of steamed bread.     

Extensional rheological properties in mixed and fermented/rested dough and relationships with steamed bread quality

In this study, sixteen wheat varieties for cultivation in China were examined for the flour characteristics using the farinograph, extensograph and rheofermentometer, uniaxial extensional rheology employing the extensograph and the Kieffer extensibility rig and biaxial extension by uniaxial compression of mixed dough with and without yeast, rested and fermented dough, and steamed bread quality including specific volume and texture properties. Three statistical analysis methods including Pearson correlation, principle component and stepwise multiple regression analysis were carried out to correlate dough properties with steamed bread quality. Biaxial extension viscosity was positively correlated with texture properties (hardness and chewiness) of steamed bread (r = 0.521–0.685, p < 0.05). Based on the correlation coefficients and the model (r² = 0.852, p = 0.003) obtained using stepwise multiple regression analysis, the best predictors for specific volume of steamed bread were the maximum resistance to extension of rested dough (r = 0.664, p < 0.01) and total work for breakage of fermented dough (r = 0.662, p < 0.01). Principal component analysis of rheological properties of fermented dough and flour characteristics provided more useful information for discriminating wheat flour quality and help breeders to select most convenient wheat flour for the steamed bread making.     

Effect of inulin with different degree of polymerization on water redistribution of steamed bread

The aim of this work was to study the influences of three types of inulin with different degree of polymerization on the water state of steamed bread during production and storage. The addition of inulin reduced the moisture content of the dough and facilitated the migration of free water to bound water. In the fermentation process, inulin had little impact on the bound water content in the dough, but could speed up the fermentation process. During the storage time, the freezable water content in steamed bread crumb decreased faster in the presence of inulin. The weaker interaction of freezable water with starch and protein chains became stronger, while the stronger interaction of tightly bound water with starch and protein chains decreased compared to the control. The changes of melting and vaporization enthalpies suggested that inulin could accelerate water migration of steamed bread from the inside to the outside.     

Effect of sourdough fermentation on the quality of Chinese Northern-style steamed breads

The effect of spontaneous and lactic acid bacteria (LAB) fermentation (Lactobacillus plantarum (LP), Lactobacillus sanfranciscensis (LS), Lactobacillus brevis (LBr) and Lactobacillus delbrueckii subsp bulgaricus (LB) strains) on the specific volume, crumb texture, volatiles profile and other aspects of steamed bread quality were studied. The addition of sourdough starter significantly decreased dough water absorption, development time and stability while increasing steam bread specific volume. The fermentation with LAB starters reached the desired pH 4 five times faster than the spontaneous starters. Steamed bread leavened with LS and LB starters had the softest crumb texture whereas LP and LBr starters produced the lowest setback viscosity. From the total of 77 compounds identified in sourdough steamed bread, ethanol and 3-methyl-1-butanol were the most abundant. All sourdough steamed breads had 22 compounds in common, which represented about 90% of the total peak area. But unique volatile compounds were present in sourdough steamed bread with different starters.     

QTL mapping for quality traits of northern-style hand-made Chinese steamed bread

QTLs for quality traits of northern-style hand-made Chinese steamed bread (CSB) were mapped based on recombinant inbred lines (RILs) derived from the cross between two Chinese winter wheat varieties, Chuang 35050 and Shannong 483. We detected eight putative QTLs for eight quality traits on seven chromosomes, 2B, 2D, 4A, 5B, 5D, 6B and 7B. The contributions of QTLs ranged from 9.88 to 64.87%. The additive effects of QTLs for color, elasticity, and stickiness were positive, with Chuan 35050 increasing the effects. Additive effects for volume, specific volume, appearance, smell, and total score were negative, with Shannong 483 increasing the effects. Two co-location QTLs were detected in the marker region Xgwm644–Xgwm193–Xgwm608b on chromosome 6B. The contributions of four QTLs for appearance, stickiness, smell and total score were very high (29.80–64.87%), indicating that these traits are controlled by major gene loci. The contribution of the smell QTL in Xissr25b–Xissr23b–Xwmc308–Xsrap7c on chromosome 4A was the highest (64.87%). We speculate that a major gene related to the smell or taste is located on chromosome 4A.     

Effects of malting on the milling performance and acceptability of bambara groundnut (Voandzeia subterranea Thouars) seeds and products

Germinated bambara groundnut was dried by three methods – oven-drying at 50 °C, in a solar drier at 38–42 °C, and sun drying at 28 ± 2 °C. The samples were milled into flour, and made into okpa, a steamed gel. Flour yield increased only in oven-dried malts. The quality of the okpa based on appearance and taste decreased with malting time; solar drying resulted in the poorest product because of its dark color.     

Studies on multigrain milling and its effects on physical,chemical and rheology characteristics of milled streams

The multigrain blends of wheat-green gram-barley in the ratio of C (100:0:0); B1 (90:5:5); B2 (80:10:10); B3 (70:15:15) were co milled using a Buhler roller mill to produce nutritious flour. The studies showed that the yield of straight run flour (SRF) increased gradually with an increase in blending of green gram and barley with wheat. The highest SRF of 79.71% was obtained from the B3 blend. The coarse bran decreased from 15.95% for the control sample to 9.52% for B3 blending. The milling yield of pollard and fine bran showed a decreasing trend from control to B3 blending. In general, flour yield decreased for reduction passages from C1 to C3 and reduction passages produced higher flour compared to break rolls for all blends. The multigrain milling resulted in an increase in protein(113.1–13.35%) and dietary fiber (2.91–4.65%) content of flour, but sedimentation values (52–38 ml), which is the index of flour strength, decreased significantly. The distributions of mineral matters and fat show wide variation among the mill streams and concentrated in coarse and fine brans. The rheological properties of flour obtained showed increased water absorption (55.8–57.5%) and decreased dough stability(5.5–2.8 min), amylograph peak viscosity (388-335BU) and setback (265-224BU) with an increase of multigrain in blends.     

Effect of stir-frying on oat milling and pasting properties and rheological properties of oat flour

Stir-frying, similar to roasting, is a key step for oat milling process in China. The oat flour milling yield of Bayou No.2 and Bayou No.8 and their corresponding flour quality were investigated under different processing conditions (160 °C, for 0, 10, 20, 30 and 40 min). Results showed that oat flour milling yield was increased after stir-frying, Bayou No.2 and Bayou No.8 reached the highest yield after a 10 min and 20 min of stir-frying, which were 45.40% and 52.96%, respectively. With the increasing of stir-frying time, the gelatinization degree and the particle size of oat flour gradually increased, while their angle of repose and L* values were reduced. RVA studies showed that the stir-fried oat flour exhibited lower peak, trough, breakdown and setback viscosities compared to not stir-fried oat flour, indicating that stir-fried oat flour formed a more stable network structure and stir-frying induced an inhibitory effect on the retrogradation of oat flour paste. Rheological analysis suggested that the low tanδ of stir-fried oat flour than that of not stir-fried oat flour, revealing that the stir-fried oat flour paste exhibited more elastic but less viscous behavior.     

Fabrication and characterization of oat flour processed by different methods

The properties of oat flour can be manipulated by processing to suit various consumption and product development needs. In this work, three different processes typically used on oat flour, namely the extrusion, drum drying and enzyme-treatment spray drying process were evaluated with respect to how each process changes the quality of the oat flour. Results showed that the extrusion process produced oat flour with the best flow ability while the enzyme-treated spray drying process led to the lowest flowability. The color of enzyme-treated spray-drying oat flour was the brightest while the oat flours turned darker after extrusion and drum drying. In addition, drum dried oat flour had the highest capability to hold water. In terms of particle size distribution, the extruded and drum dried oat flour showed smaller particle size and the particle had less complete and irregular surfaces. On the other hand, the enzyme-treated spray-drying samples showed the best particle uniformity and sphericity. The viscosity of all the treated oat flour decreased with increasing shear rate, indicating the shear thinning behavior, and a weak gel-like behavior with very high viscosity was obtained via drum drying. The results reported here can be useful and provide a baseline to fully understand how the oat flour properties changes with different processing methods to offer a wider opportunity in using oat flour for food product fortification and design.     

低筋小麦配粉及其对加工品质的影响

为改良湿面筋含量较高、面筋指数和稳定时间较低的这一类型小麦的加工品质,选择这三个指标相差较大的三个小麦品种为材料进行配粉,将湿面筋含量较高、面筋指数和稳定时间较低的小麦品种郑麦618的面粉按照0、20%、40%、60%、80%和100%比例分别与面筋指数和稳定时间较高的小麦品种新麦26或郑麦7698的面粉混合,组成不同类型的配粉,对其湿面筋含量、面筋指数、沉淀指数、面团流变学特性、淀粉RVA糊化特性以及面条和馒头的加工品质进行了比较。结果表明,当两个原粉被测指标数值差异显著时,配粉的湿面筋含量、面团流变学特征参数、峰值粘度、最低粘度和最终粘度均随着原粉数值较大一方添加比例的增加而增加。当两个原粉被测指标数值差异不显著时,配粉被测指标的数值会出现大于或小于原粉的现象,比如面筋指数、延伸性和沉淀指数;但衰减值和糊化温度不符合此规律,衰减值更接近于数值较高的原粉,糊化温度更接近于数值较低的原粉。相关性分析表明,面条总分与峰值粘度、最低粘度、衰减值呈正相关,与面团流变学特性参数呈负相关,相关系数较小;馒头总分与面筋指数、沉淀指数、形成时间、稳定时间、能量、拉伸阻力、延伸性和最大拉伸阻力呈极显著负相关,与淀粉糊化各特征值相关性不显著。上述结果证实,优质面条粉和馒头粉均不需要面筋质量过高,优质面条粉的湿面筋含量为30.3%～32.2%,面筋指数为75.2～81.4,稳定时间为4.5～7.2 min,最高粘度为2 330～2 468 cP,最低粘度为1 504～1 607 cP;优质馒头粉的湿面筋含量为30.2%～32.0%,面筋指数为70.8～81.4,稳定时间为3.5～9.1 min。面条和馒头评分结果表明,湿面筋含量较高（30%以上）,面筋指数低的这一类型的小麦可以通过搭配面筋指数较高的小麦来改良其加工 品质。     

Effects of allelic variation of HMW-GS and LMW-GS on mixograph properties and Chinese noodle and steamed bread qualities in a set of Aroona near-isogenic wheat lines

High-molecular-weight glutenin (HMW-GS) and low-molecular-weight glutenin (LMW-GS) subunits play an important role in determining wheat quality. To clarify the contribution of each subunit/allele to processing quality, 25 near-isogenic lines with different HMW-GS and LMW-GS compositions grown at two locations during the 2010 cropping season were used to investigate the effects of allelic variation on milling parameters, mixograph properties, raw white Chinese noodle (RWCN) and northern style Chinese steamed bread (NSCSB) qualities. The results showed that Glu-B1 and Glu-B3 made a large contribution to determining mixograph properties and processing quality, respectively. Subunit pairs 17 + 18 and 5 + 10, and alleles Glu-A3b, Glu-A3d, Glu-B3g and Glu-D3f made significant contributions to mixograph properties and no significant difference was detected on most parameters of RWCN and NSCSB for the allelic variation of HMW-GS and LMW-GS. The allelic interactions among glutenin loci had significant effects on wheat quality. The line with 1, 17 + 18, 2 + 12, Glu-A3c, Glu-B3b, Glu-D3c associated with superior mixograph properties, the line with 1, 7 + 9, 2 + 12, Glu-A3c, Glu-B3d, Glu-D3c had superior viscoelasticity of RWCN, and the line with 1, 7 + 9, 2 + 12, Glu-A3e, Glu-B3b, Glu-D3c had the highest total score of NSCSB. These results provide useful information for genetic improvement of the qualities of traditional Chinese wheat products.     

The final established physicochemical properties of steamed bread made from frozen dough: Study of the combined effects of gluten polymerization,water content and starch crystallinity on bread firmness

The gluten polymerization behavior, water content, starch crystallinity and firmness of Chinese steamed bread made from frozen dough were investigated and their correlations were also established in this study. The decreased degree of gluten polymerization in steamed bread was observed by the enhanced SDS-extractable proteins (SDSEPs) upon frozen storage. Less incorporation of glutenin in the glutenin–gliadin crosslinking of steamed bread mainly contributed to the decreased degree of gluten polymerization. The decreased moisture of steamed bread had a significant negative correlation with the sublimated water in frozen dough (r = −0.8850, P < 0.01). Frozen storage also induced an increase in starch crystallinity and bread firmness. A multiple linear regression model with SDS-extractable proteins, water content and melting enthalpy of starch crystals of steamed bread accounted for 86% of the variance in the natural logarithm of firmness and further revealed that starch crystallinity mainly contributed to bread firmness.     

Effects of semidry flour milling on the quality attributes of rice flour and rice noodles in China

To investigate the effects of semidry-milling on the quality attributes of rice flour and rice noodles, the properties of rice flours and cooking properties of rice noodles prepared with wet-, dry- and semidry-milled rice flours were characterized. The level of starch damage of semidry-milled rice flour at 30% moisture was significantly decreased to the level of wet-milled rice flour (P < 0.05); the whiteness of dry-milled rice flour was decreased compared with wet-milled rice flour (P < 0.05), while that of semidry-milled rice flour was not; the wet- and semidry-milled rice flours showed similar morphology and water hydration properties; the dry milling method reduced significantly the hardness, chewiness, and resilience of rice noodles (P < 0.05) compared with wet-milling, but semidry-milling did not; the cooking qualities of rice noodles produced by semidry-milling were comparable to wet-milling. It indicated the semidry-milling at 30% moisture may provide the protective effects on the characteristics of rice flours, which could be used to produce similar qualities of rice noodles to the wet-milling.     

中麦175馒头和面条品质稳定性分析

为给优质小麦育种和生产提供参考依据,以优质小麦新品种中麦175于2010-2011年度在河北和北京14个地点的样品为材料,分析了磨粉品质、面粉和面片颜色、面团流变学和淀粉糊化特性、馒头和面条加工品质。结果表明,中麦175为馒头和面条兼用型优质品种,特点是软质、中偏弱的面筋强度、面粉颜色白,多数品质性状较稳定,籽粒硬度、PPO活性、面片a*值、稳定时间、拉伸面积、延展性和最大抗延阻力的变异系数较大,馒头加工品质地点间变异大于面条。磨粉品质和面团流变学参数对馒头加工品质有显著影响,籽粒硬度和出粉率对馒头表面颜色有显著负向影响,相关系数分别为-0.82(P<0.01)和-0.58(P<0.05);面粉L*值高,馒头加工品质好,二者相关系数为0.72(P<0.01);吸水率与馒头总分呈显著负相关(r=-0.84,P<0.01),稳定时间、拉伸面积、延展性和最大抗延阻力与馒头总分呈显著正相关,相关系数分别为0.85(P<0.01)、0.77(P<0.01)、0.62(P<0.05)和0.70(P<0.01)。降低PPO活性和吸水率,提高蛋白质含量、出粉率和黄色素含量可以改善面粉和面片颜色的亮白度,增加部分黄度,形成消费者可接受的奶白色。淀粉糊化特性对馒头和面条加工品质无显著影响。上述信息对改良小麦品质的稳定性有重要意义。     

Evaluation of the rheological properties of dough and quality of bread made with the flour obtained from old cultivars and modern breeding lines of spelt (Triticum aestivum ssp. spelta)

This work evaluates rheological properties of dough and quality of bread prepared from the flour of ancient varieties and modern breeding lines of spelt compared to common wheat. Spelt flours of old varieties exhibited similar water absorption; the largest was noted in the STH-8 line flour. Spelt doughs had longer development time and were more stable than wheat dough. The doughs made of old spelt varieties were more resistant to extension than that produced from new lines flours. Of the spelt breads, this of the STH-8 line spelt line had the largest loaf volume but smaller than wheat bread. In addition, spelt doughs had similar porosity; the most porous was the bread baked from the Frankenkorn cv, Schwabenkorn cv and STH-8 line flours. Moreover, the crumb of the bread manufactured from the flours of spelt variety Frankenkorn and the STH 28-4614 line showed the greatest resistance to compression and the smallest compressibility.     

山西主栽小麦品种蒸煮食品加工性比较

为了解近年山西主栽小麦品种的品质性状及蒸煮面食制品加工适宜性、筛选优质面条和馒头小麦品种,以晋麦95号为对照,对山西省近五年21个主推小麦品种的籽粒、面粉品质性状及面条、馒头加工品质特性进行了系统检测与分析。结果表明,山西省近五年主推小麦品种多为中强筋品种,所占比例为63.6%,大部分品质性状的遗传多样性较为丰富;适宜制作面条的小麦品种有15个,占所有品种的68.2%。21个主推小麦品种馒头综合评分平均为82.0分,变化范围77.0～88.5分;达到良好馒头标准(80～90分)的共有14个品种;晋麦92、晋麦47、运旱139-1、运旱805、济麦23、品育8012、运旱618、晋麦101的馒头感官评分均高于对照。面条、馒头感官评分与小麦面粉的形成时间、稳定时间呈极显著正相关(P<0.01),与弱化度呈显著负相关(P<0.05),与质构参数(TPA)的内聚性、胶黏性和咀嚼度均呈极显著正相关(P<0.01)。山西近五年主推小麦品种有较好的蒸煮加工品质特性。     

青海省春小麦品种加工品质研究

为了为青海省春小麦品种品质改良提供理论依据,将115份春小麦品种(系)于2000年种植在青海省西宁市,并对其籽粒品质及馒头和面条加工品质进行了评价。结果表明,参试品种(系)筋力较差、评分较低,但品种间变异幅度较大。外引品种如小冰麦33、M99-90、高优503、格兰尼、加5和野猫的馒头和面条品质较好。蛋白质含量和质量对馒头品质的影响较大,在试验Ⅰ中,稳定时间与馒头体积、表面色泽、外观形状和韧性呈极显著正相关,相关系数分别为0．49、0．58、0．45和0．46。蛋白质质量主要影响面条质地,淀粉特性与面条质地和外观均相关密切,如峰值粘度与适口性、韧性、粘性和光滑性呈极显著正相关,相关系数分别为0．58、0．61、0．59和0．48。提高蛋白质质量扣淀粉特性有助于改善面条品质。尽管青海的生态条件对面粉颜色、面筋强度和淀粉粘度有较大负面影响,但通过遗传选择提高青海省小麦品种的馒头和面条品质是可能的。     

小麦新品种郑麦9694配粉特性的研究

用小麦新品种郑麦9694与优质强筋小麦郑麦9023进行配粉,测定粉质仪参数和馒头加工品质,结果表明,郑麦9694的馒头加工品质较好,随着郑麦9023添加比例的增加,可使馒头的比容、宽高比、内部结构、弹性、韧性、黏性和食味得分显著提高,总分有了一定的提高;但郑麦9023的添加超过一定的比例后,馒头比容、内部结构和弹性得分则又下降了,表面色泽虽然没有变化,但表面结构得分则随着郑麦9023比例的增加呈下降趋势。最适宜的配粉比例为70∶30,即在郑麦9694中搭配30%的郑麦9023,其湿面筋含量、粉质仪参数等达到优质馒头粉标准,可显著改善馒头的加工和制作品质。     

馒头品质评价方法探析

以参加陕西省1999／2000年度区域试验的19个小麦品系为试验材料，在对其籽粒品质性状和馒头品质的感官评价与质构仪测试的基础上，通过相关分析对馒头品质评价方法、评价指标进行了探讨。研究结果表明，评价馒头品质的主要感官指标为色泽、外观形状；度量指标为体积；质构仪测试指标主要为弹性和回复性；当馒头的感官品质及度量体积较好时，质构仪测试的弹性和回复性数值越高，馒头品质越好。