高粱超微全粉对面团流变学特性及馒头品质的影响

为研究高粱超微全粉对面团流变学特性及馒头品质的影响,将高粱超微粉碎后按一定比例添加到小麦面粉中,测定混合粉的流变学特性,并对混合粉馒头品质进行评价。结果表明:高粱超微全粉添加量较低时(5~10%),混合粉的各项粘度值和峰值时间增加;添加量增加到15~20%时,各项粘度值和峰值时间降低,糊化温度差异不显著。高粱全粉的添加使混合粉的吸水率有所增加。添加量达到10%及以上时,形成时间、稳定时间、粉质指数、拉伸曲线面积、拉伸阻力和延伸度均显著降低。混合粉馒头除色泽外的各项感官指标得分显著降低。馒头硬度和咀嚼性显著增加,粘附性和内聚性先增加后降低,弹性降低,回复性无明显变化规律。气孔延长度差异不大,其他图像分析指标差异显著。高粱超微全粉的添加改变了混合粉的主要成分特别是淀粉和蛋白质的构成与含量,对面团流变学特性及馒头品质均有较大影响。     

Effect of gamma‐ray irradiation on the physicochemical properties of flour and starch granule structure for wheat

Effect of gamma irradiation on the physicochemical properties of flour and starch granule structure of wheat was compared to non‐irradiated wheat. The moisture content of wet gluten and titratable acidity of wheat flour were significantly affected by gamma irradiation. This treatment also destroyed the starch granules of wheat grain and their breakage augmented as the dose of gamma irradiation increased, apparently resulting in the increase of small starch granules. Probably, these results were due to the disruption of large molecule, such as proteins, lipids and starch. The irradiated wheat flour for RVA pasting properties (flour viscosity) was also evaluated. Besides the difference in RVA profile, starch pasting curves showed a considerable decrease for six main parameters as gamma irradiation dose at different velocity increased.     

不同粒径小米粉对面团流变特性及馒头质构特性的影响

为研究小米粉添加对面团流变特性和馒头制品质构特性的影响,分别选取不同粒径的粳性和糯性小米粉,利用损伤淀粉测定仪、快速黏度分析仪等对不同小米粉的损伤淀粉含量和糊化特性进行分析,通过流变仪测定小米面团的流变学特性,结合扫描电镜观察小米面团微观结构变化,并利用质构仪测定小米馒头的质构特性。结果表明：随着小米粉粒径的减小,多数品种小米粉（除冀谷39和汇华金米）损伤淀粉的碘吸收率增加;受直支比的影响,相同目数下,粳性小米粉的峰值黏度、谷值黏度、最终黏度和回生值较糯性小米粉大。流变学研究表明,除汇华金米和冀谷39,储能模量与损耗模量随角频率增加总体上升。扫描电镜观察发现小米粉的添加使面团结构更加松散。小米粉的添加会对馒头质构性质中硬度、咀嚼性和弹性等有一定程度的负面影响。主成分分析表明馒头咀嚼性、损伤淀粉、峰值黏度、谷值黏度、最终黏度、崩解值和回生值可作为区分粳糯品种和馒头品质特征的指标。     

糯小麦粉添加量对配粉流变学特性及馒头品质的影响

将糯小麦粉与普通小麦粉进行梯度配粉,研究不同糯小麦粉添加量对配粉糊化黏度、粉质特性和面团流变学特性的影响;采用质构和感官评价相结合的方法评价其对馒头品质的影响,确定合适的糯小麦配粉比。结果表明：随着糯小麦粉添加量的增加,配粉的糊化温度、峰值黏度、衰减度和回生值等快速黏度分析参数均呈现下降趋势,尤其是回生值降低显著。配粉的吸水量随糯小麦粉添加量的增加逐渐增大,面团的形成时间和稳定时间缩短,粉质指数降低;但当添加量增加至25.0%时,粉质特性各指标均产生显著性改变。不同配粉面团随着醒发时间的延长,面团拉伸曲线面积、拉伸阻力和拉伸比等指标均呈现一定的增大趋势,但延伸度却随醒发时间延长而降低。糯小麦粉配粉比例对馒头的质构和感官特性具有较大影响,适宜的糯小麦粉配粉比为20.0%～30.0%,25.0%配粉比使馒头具有较好的质构,感官总评分达到最大值。     

Nutritional and functional added value of oat, Kamut, spelt, rye and buckwheat versus common wheat in breadmaking

BACKGROUND: Multicereal/pseudocereal blends based on major and minor seeds with high nutritional profile appear as a promising strategy, hardly explored, to obtain enhanced value grain‐based foods such as bread. RESULTS: In a preliminary stage the suitability of minor/ancient cereals (rye, oat, Kamut^® wheat, spelt wheat) and pseudocereals (buckwheat) was assessed in single (100% of wheat flour replacement) and multigrain (from 20 to 44% of wheat flour replacement) matrices. The research allowed identification of the qualitative (oat, rye, buckwheat) and quantitative (up to 75% of wheat flour replacement) grains in the mixed matrices providing enhancement of nutritional quality (higher protein content, higher mineral content, lower digestible starch, higher viscous fibre content, higher resistant starch content, source of antioxidants) and minimisation of techno‐functional impairment and sensory depreciation of the resulting breads. CONCLUSION: The quality profile of associated mixtures of oat, rye, buckwheat and common wheat flours (20:20:20:40 w/w/w/w) endorsed the proposed grain blend as suitable to make highly nutritious, modern and innovative baked goods meeting functional and sensory standards in terms of nutritional added value (improved dietary fibre fractions, minerals and antioxidant activity, slower starch hydrolysis), palatability (high sensory scores), convenience (extended keepability during storage) and easy handling during processing. Copyright © 2011 Society of Chemical Industry     

Effect of damaged starch levels on flour-thermal behaviour and bread staling

The effect of the amount of damaged starch in two different flours (wheat and triticale) on the bread quality and its behaviour during storage has been analysed. Two wheat and one triticale flour cultivars were milled in a disc mill to obtain different levels of damaged starch. Differential Scanning Calorimetry (DSC) and Rapid Visco Analyser (RVA) were used to characterize the flour properties and TA-XT2 textural analyses were made on breadcrumb. The effect of the damaged starch content on the bread firming, the amylopectin retrogradation and starch-pasting properties were studied in order to establish any relationship between damaged starch and bread staling. DSC analysis showed that the damaged starch content changed the thermal behaviour of flour–water mixtures: the higher the levels of damaged starch the lower the starch-gelatinization enthalpy and the higher the melting enthalpy of amylose–lipid complexes. The amount of amylopectin retrogradation and breadcrumb firming increased with the damaged starch content at the beginning of storage time; however, differences were decreasing at final storage time. The flour viscosity during pasting decreased as their damaged starch content increased.     

汽爆高粱全粉馒头的研制

目的:研究汽爆对高粱功能成分的影响以及汽爆高粱全粉添加量对面团和馒头质构特性的影响。方法:汽爆高粱以蒸汽为汽爆介质,研究0.8 MPa压力维压5 min的条件下高粱中功能成分的变化;将汽爆高粱全粉按不同比例添加到小麦面粉中制作馒头,用质构仪测定面团和馒头的质构特性,用白度仪测定馒头白度值,对馒头食用品质进行感官评价,并讨论了汽爆高粱全粉的适宜添加量。结果表明:高粱经汽爆处理后,高粱中的功能成分含量发生变化:不溶性膳食纤维和单宁含量明显下降,抗性淀粉、总多酚和总黄酮含量提高。添加适量的汽爆高粱全粉可改变小麦面团的特性及馒头的品质,在本实验中汽爆高粱全粉的适宜添加量为25%,此时硬化速率低,馒头的食用品质较好。结论:汽爆有利于降解不溶性膳食纤维和单宁含量,促进功能成分的溶出,抗性淀粉、总多酚和黄酮含量增加;汽爆高粱全粉可以添加到馒头中,可以为高粱的开发利用提供参考。     

山农紫糯小麦粉理化性质分析及其馒头产品的开发

糯小麦粉由于直链淀粉含量很低而被赋予其独特的理化性质。本实验对山农新培育出的紫糯小麦品种制粉的理化和营养性质进行了测定,并与普通小麦粉配粉制作馒头,通过质构仪检测试验和感观评价相结合的方法对馒头品质进行了研究,从而确定了山东农业大学新培育紫糯小麦品种开发馒头产品的最佳工艺。试验结果表明:山农紫糯小麦粉的脂肪、蛋白质、灰分和蛋白质中清蛋白、醇溶蛋白、谷蛋白含量比普通面粉高,而淀粉和球蛋白含量比普通面低;其糊透明度、谷值黏度、最终黏度、糊化温度较低,但崩解值、峰值黏度、回生值高。添加15%的紫糯小麦粉可显著的改善馒头的表皮色泽,并且对馒头的弹性、黏着性、黏聚性和回复性影响最大,此时馒头的总评分达到最大值。     

Promoting dough viscoelastic structure in composite cereal matrices by high hydrostatic pressure

The impact of high hydrostatic pressure (HP) treatment on dough viscoelastic reinforcement of highly-replaced wheat cereal matrices has been investigated. The gelatinisation/pasting and gelling profiles of HP hydrated oat, millet, sorghum and wheat flours, and the small and large deformation rheological parameters of blended wheat/non-wheat doughs were determined. Oat, millet, sorghum and wheat hydrated flours, at dough yield (DY) 160 and 200, were treated for 10 min at 0.1, 200, 350 or 500 MPa. Regardless the nature of the cereal, HP changes flour viscometric features, particularly in softer doughs (DY 200), leading to increased values for viscosity parameters, concerning pasting and paste cooking. Incorporation of 350 MPa pressure-treated flours into bread dough formulation provided increased dynamic moduli values, particularly for wheat and oat/wheat blends, associated to a reinforced dough structure. Highly-replaced composite dough samples treated at 500 MPa proved to be extremely stiff, resistant to stretch, low cohesive and low extensible, and thus not suitable for breadmaking.     

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.     

黑小麦全粉的流变学特性及复配混粉馒头的品质研究

通过对黑小麦全粉、与对照样特精粉复配混粉的面筋数量与质量测定,对黑小麦全粉占10%、15%、20%、25%、30%、40%、50%复配混粉进行流变学特性指标的测定及制作馒头成品以评价。结果表明:不同复配比例的混粉湿面筋数量表现比例越大含量越高;黑小麦全粉的流变学特性较差;复配混粉也都低于对照样特精粉的流变学指标;黑小麦全粉单独并不适合制作馒头,当复配比例在10%~15%时,馒头评价总分在80以上。     

膨化小米粉对挂面加工特性的影响

为充分利用小米杂粮资源,有效提高在面制品中的添加量,增加挂面的花色品种,本文将膨化小米粉按照一定比例添加到小麦粉中,对所得混合粉的粉质特性、拉伸特性、糊化特性进行了分析,同时对其混合粉制作的挂面品质进行了分析研究。结果表明:添加膨化小米粉可有效改善面团的粉质、拉伸和糊化特性;适量添加可有效降低挂面的最佳蒸煮时间,增强挂面的弹性和硬度。在该实验条件下,综合分析混合粉的粉质、拉伸特性和糊化特性,并通过测试分析挂面的蒸煮特性、断裂强度、熟挂面的剪切力等,最终确定挤压膨化小米粉最佳添加量为6%,为其在面制品中的应用提供了参考。      

胡芦巴胶对混合粉制面包及生面团品质的影响

去皮高粱粉和粟米粉作面包用粉的替代物，以不同比例添加使用。胡芦巴胶部分替代面粉，替代率可达０．９％，研究了胡芦巴胶对流变特征及面包品质的影响。添加胶越多，生面团吸水量亦越高；添加胡芦巴胶后，生面团的稳定时间、断裂时间和机械耐力指数均有提高。按４∶１的面粉／高粱粉配方，添加０．６％胶可增大面包体积２１．８％，而０．９％的胶添加量能增大面包体积２１．３８％．     

Effect of dietary fibre enrichment on selected properties of gluten-free bread

The enrichment of gluten-free baked products with dietary fibre seems to be necessary since it has been reported that coeliac patients have generally a low intake of fibre due to their gluten-free diet. In the present study different cereal fibres (wheat, maize, oat and barley) were added at 3, 6 and 9 g/100 g level into a gluten-free bread formulation based on corn starch, rice flour and hydroxypropyl methyl cellulose (HPMC). Doughs were evaluated based on consistency, viscosity and thermal properties. Results showed that maize and oat fibre can be added to gluten-free bread with positive impact on bread nutritional and sensory properties. All breads with 9 g/100 g fibre increased the fibre content of control by 218%, but they were rated lower than those with 3 and 6 g/100 g fibre due to their powdery taste. The formulation containing barley fibre produced loaves that had more intense color and volume comparable to the control. During storage of breads a reduction in crumb moisture content and an increase in firmness were observed. The micrographs of the crumb showed the continuous matrix between starch and maize and/or oat fibre obtaining a more aerated structure.     

Properties of Korean Amaranth Starch Compared to Waxy Millet and Waxy Sorghum Starches

Characteristics of waxy type starches isolated from amaranth, waxy millet and waxy sorghum harvested in Korea were evaluated. Shapes of all starch granules were polygonal or slightly round and the surfaces of waxy millet and waxy sorghum starch granules showed visible pores. Amylose contents of the three starches were between 3.2–6.0% and amaranth starch showed the highest water binding capacity (WBC) (130.7%). The swelling power and solubility of amaranth starch studied at 65.0–95.0°C increased about 13.7‐ and 14.0‐fold, respectively, with increase in temperature. Swelling power of waxy sorghum starch was the highest (72.6 at 95°C) among the starches studied, while amaranth starch had a constant swelling power and its rate of solubility increasely only slowly at temperatures higher than 75°C. From RVA data, initial pasting temperatures of amaranth, waxy sorghum and waxy millet starches were 75.7, 73.3 and 75.2°C, respectively. Peak viscosity, breakdown, and setback from trough of amaranth starch were 68.3, 16.7 and 7.5 RVU, respectively, which were the lowest values among the starches investigated. Using DSC, onset temperature of gelatinization of amaranth starch was 1.5–4.0°C higher than those of waxy sorghum and millet starches, corresponding to the RVA result. The enthalpies of gelatinization of the starches studied in our laboratory were in the range of 8.5–12.7 J/g with decreasing order of waxy sorghum > amaranth > waxy millet starch.     

Nutritional,Functional and Physical Properties of Extrudates from Blends of Cassava Flour with Cereal and Legume Flours

Low protein and poor functionality limit the use of cassava flour in snack foods, which were modified using blends with cereal and/or legume flours. Native, malted (using alpha-amylase) as well as malted and pre-gelatinized was blended with cereal (finger millet and whole wheat flours) and/or legume (chick pea flour). Extrudates were prepared at a screw speed of 100 rpm and die temperature of 180 °C. Malted flour based extrudates had lower starch content than native flour. Gram malted cassava based blends gave products with the highest protein. In vitro starch digestibility was the highest for pre-gelatinized flour based mixes. Extrudates with low fat and energy have scope as low calorie snacks for obese and diabetic people.     

几种杂粮粉面团流变学特性的研究

在研究小米粉对面团流变学特性影响的基础上,用燕麦粉、苦荞粉、高粱粉分别与小米粉复配成35%的杂粮粉添加到小麦粉中,用粉质仪和拉伸仪研究分析燕麦粉、苦荞粉、高粱粉分别与小米粉复配的混合面团的流变学特性。结果表明:与添加35%小米粉单一杂粮粉的面团粉质特性相比较,燕麦和小米复配粉、苦荞和小米复配粉、高粱和小米复配粉的混合面团的吸水率、形成时间、稳定时间、粉质质量指数均更高,综合粉质特性五项指标得出:添加燕麦和小米、苦荞和小米、高粱和小米复配粉的混合面团的粉质特性要比单一添加小米粉好。与添加小米粉单一杂粮粉的面团的拉伸参数比较,苦荞小米复配粉的拉伸特性更好,燕麦小米复配粉的拉伸特性较差,而高粱粉添加量达到20%以上,拉伸特性很差,无法进行拉伸实验。建议制作杂粮面制品时,应根据产品需求及混和粉流变学特性选择合适的杂粮和添加量进行复配。      

Investigation of product quality, sensory profile and ultrastructure of breads made from a range of commercial gluten-free flours compared to their wheat counterparts

Bread is a major staple food consumed daily in all parts of the world. A significant part of the human population cannot tolerate gluten, a storage protein found in wheat, rye and barley, and therefore, products made from alternative cereals are required. During this study, the bread-making potential of seven gluten-free flours, wheat and wholemeal wheat flour was compared. Fermentation potential of the different flours was determined, showing that dough development height of gluten-free and wholemeal wheat samples was lower than for wheat and oat flour. Apart from standard bread quality parameters such as loaf-specific volume and physical crumb texture, also water activity and shelf life have been determined. The shelf life of gluten-free breads was reduced compared to wheat bread. Aroma profiles were evaluated by a trained panel. Wheat, oat and wholemeal wheat breads were liked moderately, while the remaining samples had lower liking scores. Crumb grain characteristics were investigated using image analysis, and microstructure was observed by scanning electron microscopy. Overall, only breads produced from oat flour were of similar quality to wheat bread, and the utilization of buckwheat, rice, maize, quinoa, sorghum and teff flours resulted in breads of inferior quality.     

The content of proteic and nonproteic (free and protein-bound) tryptophan in quinoa and cereal flours

The content of proteic and nonproteic (free and protein-bound) tryptophan and of proteins in quinoa, wheat, rice, maize, barley, oat, rye, spelt, sorghum and millet flours was determined. Protein content and proteic tryptophan of quinoa were similar to that of wheat and spelt, but higher than in other cereals. Free tryptophan in quinoa flour showed values similar to those of wheat, oat and sorghum Kalblank, lower than those of barley, spelt and pearl millet, but higher than in rice, maize, rye, sorghum DK 34 – Alabama hybrid. In addition, nonproteic tryptophan appears bound both to water soluble proteins and to proteins soluble at pH 8.9. The results are discussed regarding the importance of the nonprotein tryptophan fraction, the only one able to enter the brain, that is more easily absorbed, so guarantees a greater amount available for uptake by the central nervous system.     

小米粉含量对小米小麦混合粉及其挂面品质特性的影响研究

将小米粉按照10%~80%的比例添加到小麦粉中,对小米小麦混合粉的粉质特性和糊化特性进行了分析,同时对由混合粉制作成的挂面的品质特性进行了分析研究。结果表明:1)随着小米粉添加量的增加,小米小麦混合粉的峰值黏度、最低黏度、最终黏度、回生值、衰减值和峰值时间都在降低,形成时间、稳定时间、粉质指数都是先降低再升高。2)挂面蒸煮损失率不断升高,干物质吸水率不断下降。小米添加量≤30%时,挂面品质比较好,添加量≤60%时,品质尚可,添加量60%时,挂面品质下降比较大。3)小米粉的添加量、小米小麦混合粉的RVA特性、粉质特性与混合粉挂面的蒸煮品质特性有非常高的相关性。