荞麦粉添加对混合粉面团流变学特性的影响

该试验将荞麦粉按0％～60％的添加量添加到小麦粉中,使用Mixolab混合仪、粉质仪以及拉伸仪测定混合粉面团的流变学特性,研究不同荞麦粉添加量对混合粉面团流变学特性的影响.研究结果表明,随着荞麦粉添加量的增加,混合粉面团的吸水率、延伸性和能量下降,稳定时间和形成时间整体小于纯小麦粉面团,弱化度整体大于纯小麦粉面团,评价...     

含有加州杏仁粉和烘焙酶制剂的面团体系的流变学特性研究

本文主要应用动态流变仪测定了美国加州杏仁粉(全脂和脱脂)百分含量分别为0%、12.5%、25%、37.5%和50%的面团的粘弹性模量(G″和G′)在频率和温度变化过程中所呈现出的变化趋势;以及在频率和温度相同的情况下,杏仁粉含量的变化对面团的G″和G′大小的影响;并进一步探索了淀粉酶处理对面团流变学特性的影响。结果表明:(1)在频率扫描过程中杏仁粉对面团的G″和G′都有明显的影响,含有全脂杏仁粉的面团的G″大于含有相同比例脱脂杏仁粉面团的G″,而含有全脂杏仁粉的面团的弹性模量G′却比含有相同比例脱脂杏仁粉的小,从而推断杏仁粉中的油脂对面团的流变学特性具有显著的影响;(2)在相同的频率时小麦粉面团的G″和G′比分别含有12.5%和25%的杏仁粉(全脂和脱脂)的面团的大,而分别含有37.5%和50%的杏仁粉的面团的G″和G′更大,这可能是由于杏仁蛋白质与小麦蛋白质发生了某种相互作用所致;(3)在升温过程中,添加全脂和脱脂杏仁粉都会使面团的G″和G′减小;在降温过程中,加入杏仁粉(全脂和脱脂)使面团的G′减小,但含有脱脂杏仁粉面团的G′大于含有全脂杏仁粉面团的G′,而加入杏仁粉对面团的G″在降温过程中的变化影响不显著;(4)在频率变化、升温和降温过程中,加入淀粉酶都会使面团的G″和G′减小。     

糯麦粉对冷冻面团发酵流变特性和面包烘焙特性的影响

采用发酵流变测定仪和质构分析仪研究不同比例的糯麦粉对冷冻面团发酵流变学特性和面包烘焙特性的影响。结果表明：无论面团冷冻与否,随着糯麦比例增加,面团发展的最大高度(Hm)和持气率(R)逐渐下降,而气体释放曲线最大高度(H＇m)和CO2产气量(Vco2)在一定程度上增加。随着冻藏时间的延长,面团各种参数(Hm、H＇m、R等)逐渐降低,但是下降的幅度随糯麦粉添加量的增加而减小,如与冻藏7d相比,添加质量分数0%、10%、20%和30%的糯麦面团经冻藏60d后Hm分别下降了12.9%、9.6%、7.7%和7.5%,而R则分别下降了2.8%、2.1%、1.6%和1.7%。在冷冻贮藏过程中,面包品质虽有一定程度的下降,但添加糯麦粉的面包品质下降程度较慢,抗老化效果好,且由感官评定可知,冻藏不同天数后,添加10%糯麦粉的面包最易受人们喜爱。     

苦荞粉面团流变学特性的研究

面团流变学特性对于确定焙烤食品的加工工艺及相关的工艺数据有重要的指导意义。本实验研究了苦荞粉的流变学特性,发现苦荞粉不适宜单独加工焙烤食品,必须添加适量的辅料。通过添加不同比例的谷朊粉可不同程度地改善苦荞粉面团的流变学特性,进而改变其加工特性。     

The Interplay Between the Main Flour Constituents in the Rheological Behaviour of Wheat Flour Dough

There is still considerable debate in the literature about the respective roles of starch and gluten in both the linear and non-linear rheology of wheat flour dough. Hence, to elucidate the individual contributions of gluten and starch to the overall dough behaviour, the rheological properties of dough and mixtures of different gluten-starch ratios were studied systematically in shear and extension, by means of an adequate rheological toolbox consisting of linear small amplitude oscillatory shear tests and non-linear tests such as creep-recovery in shear and uniaxial extension. The starch component plays a pivotal role in linear dough rheology. With increasing starch content, the linearity limit observed in oscillatory shear tests decreases as a power-law function. Starch also clearly affects the extensional viscosity at small strains. Consequently, in the linear region differences between different gluten systems may become obscured by the presence of starch. As breadmaking qualities are known to be intrinsically linked to the gluten network, it is imperative to probe the non-linear behaviour of dough in order to expose differences in flour quality. The quality differences between a strong and a weak flour type were revealed most clearly in the value of the strain-hardening index in uniaxial extension and the total recovery compliance in non-linear creep-recovery tests. Notwithstanding its earlier successful application to pure gluten gels, the accuracy of the critical gel model in predicting the linear rheological properties of dough was found to be limited, due to dough having a small linearity limit and a finite longest relaxation time.     

小麦储藏对面粉品质和烘焙性能的影响

根据小麦在陈化过程中的物理化学变化,论述了小麦陈化对其制粉特性及烘焙性能的影响;并分述了陈化对小麦种类,小麦淀粉,小麦蛋白,小麦脂质及小麦营养价值的影响,指出了加速小麦陈化的外部因素为温度。水分,相对湿度,储存环境中氧气含量和时间等。     

添加荞麦多肽粉对面团流变学特性的影响

将不同水解条件下得到的荞麦多肽粉按不同浓度梯度分别添加到强筋和弱筋面粉中,探讨荞麦多肽粉对面团流变学特性的影响。结果表明:添加不同量荞麦多肽粉的面团,吸水率均随荞麦多肽粉添加量的增加而不断降低,当超过8%添加量后,吸水率受到的影响较小;面筋的含量随着荞麦多肽粉添加量的增加呈现先增加后减小的趋势;面团形成时间和稳定时间随荞麦多肽粉添加量的增加均呈先减小后增加的趋势,弱化度呈上升趋势,评价值也呈现一直增加的趋势。从拉伸特性来看,随着荞麦多肽粉添加量的增加,面团的延伸性变好,拉伸阻力在高浓度添加量的情况下比原面粉大,拉伸能量则呈现一直增加的趋势。总体而言,添加荞麦蛋白粉及其多肽粉对面团粉质及拉伸特性均具有促进作用。     

Effect of Starch Substitution by Buckwheat Flour on Gluten-Free Bread Quality

The buckwheat flour was studied as a potential healthy ingredient for improving the nutritional and technological quality of gluten-free bread. The effect of exchange of gluten-free formulation mass by buckwheat flour in 10, 20, 30 and 40 % was investigated. The increase in loaf specific volume with rising buckwheat flour addition was observed. Compared with the control sample, decrease in whiteness and increase in redness and yellowness of crumb were noticed. The rising amount of buckwheat flour in gluten-free bread formulation caused a decrease in crumb hardness during storage. This was in agreement with the decrease in starch gelatinisation enthalpy with the increasing amount of buckwheat flour in gluten-free formula in comparison with the control sample. Buckwheat flour could be incorporated into gluten-free formula and have a positive influence on bread texture and delaying its staling.     

Rheological Characteristics of Pectin and Sodium Carboxymethyl Cellulose

The dynamic viscosities of pectin and sodium carboxymethyl cellulose (SCMC) were determined in the presence of 60 and 70% sugar concentration. The effect of dissolving citric acid, after or before the complete dissolution of pectin and sodium carboxymethyl cellulose on the dynamic viscosity were also investigated.     

羧甲基纤维素钠对面团特性及面包品质的影响

研究了添加羧甲基纤维素钠对面团特性、面包烘焙特性及面包货架期的影响.结果表明,添加CMC-Na能使面团的吸水率增加,面团的形成时间、稳定时间、断裂时间缩短,评价值降低,面团的拉伸能量、拉伸阻力、拉伸长度也降低;添加适量的CMC-Na可改善面包的焙烤特性,增加面包的体积,提高面包的含水量,改善面包的纹理结构,质地和口味等,延长面包的货架期;在本实验条件下,CMC-Na的添加量不宜超过6‰.     

食品添加剂对面团动态流变学及冷冻面团烘焙特性的影响研究

应用动态流变仪,研究了食品添加剂硬脂酰-2-乳酸钠(SSL)、刺槐豆胶(LBG)、葡萄糖氧化酶(GOD)、木聚糖酶(XY)及葡萄糖氧化酶和木聚糖酶(GOD+XY)复合对面团动态流变学特性以及对冷冻面团烘焙特性的影响。结果表明,在频率0.1～40Hz扫描过程中,与未添加任何添加剂的面团(空白面团)相比,添加SSL的面团弹性模量、粘性模量和损耗角正切都减小;添加LBG的面团弹性模量和粘性模量增大,损耗角正切减小;添加GOD的面团弹性模量增大,粘性模量和损耗角正切减小;含有XY的面团弹性模量和粘性模量减小,损耗角正切增大;而含有GOD+XY的面团弹性模量和粘性模量增大,损耗角正切减小。升温扫描过程中,在低于55℃时弹性模量和粘性模量变化较小。随温度的升高,大约从55℃开始弹性模量和粘性模量迅速增加到最大值,然后又快速降低。采用6个配方研究了不同添加剂及其不同配比对冷冻面团烘焙特性的影响,实验发现酶制剂、乳化剂及胶体复合明显提高了冷冻面团的烘焙特性,缩短了醒发时间、增大了面包比容和降低了面包瓤硬度,这表明酶制剂、乳化剂和胶体在面团体系中存在协同增效的作用。     

苦荞-小麦混合粉流变学特性及烘焙特性研究

该文对苦荞小麦混合粉粉质特性、拉伸特性进行系统研究。随着苦荞粉比例增加,形成时间、稳定时间缩短,弱化度上升,评价值下降,拉伸参数均呈下降趋势;且苦荞粉比例越大,下降幅度越大。另外,面包烘焙实验表明,苦荞添加量为10％和20％时,苦荞面包尚有较好烘焙特性,添加量增至30％时,烘焙特性显著下降,添加量达40％或50％时,烘焙特性极差。     

Soybean Flour Lipoxygenase Isozymes Effects on Wheat Flour Dough Rheological and Breadmaking Properties

The effects of soy flour from LOX null mutant isolines and purified LOX isozymes on the rheological and breadmaking properties of a commercial hard wheat flour were investigated. Wheat flours were fortified with either 3% soy mutant flours alone, or in the presence of 0.2% and 1% linoleic acid. Purified LOX 2 isozyme had the greatest effect among LOX isozymes on dough extensibility and strength. Linoleic acid substrate addition reduced dough extensibility and strength. The L2L3 null isoline mutant for L1 resulted in the largest increase in bread volume. A reduction in bread firmness occurred after 5 day storage for all three single null mutant-containing samples in the presence of 1.0% linoleic acid substrate.     

Effect of Carob Flour Addition on the Rheological Properties of Gluten-Free Breads

In this study, the rheological properties of gluten-free doughs from rice flour containing different amounts of carob flour were investigated. Water added changed in response to the carob amount. Dynamic oscillatory and creep tests were performed in order to gain knowledge on the rheological behaviour of doughs, which is essential for the control of the bread-making procedure and the production of high-quality bread. Simple power law mathematical models were developed in order to evaluate the effect of carob and water added in dough rheological behaviour. Creep data evaluation demonstrates that an increase in water content decreased the resistance of dough to deformation and, therefore, dough strength, whereas carob flour increased the elastic character and structure strength of the dough. This was also found in dynamic oscillatory tests. Increased amounts of carob flour led to an increase in bread dough elastic character since fibre addition elastifies and strengthens the dough structure. Moreover, doughs exhibited a solid-like viscoelastic character, with the storage modulus (G′) predominant over the loss modulus (G″). Dough rheological properties have an important effect on baking characteristics. Rheological experiments and applied mathematical models can provide us with good knowledge of rheological behaviour and dough viscoelasticity prediction. Therefore, dough samples containing carob-to-water ratios of 10:110 and 15:130 can be considered to possess a balance between the viscous and elastic properties compared to the other samples.     

丙烯酰胺抑制剂对曲奇面团流变学和烘焙特性的影响

通过引入天冬酰胺酶和/或甜菊苷到曲奇配方中替代部分糖以抑制其生产过程中丙烯酰胺的生成,分析单独或同时添加这两种配料时曲奇面团的动态流变学特性、硬度和曲奇饼干的烘焙感官特性。结果表明：当单独添加天冬酰胺酶(1000 ASNU)时可降低曲奇样品中天冬酰胺含量(0.045mg/g)的67%,从而抑制95%丙烯酰胺的生成,且不会影响曲奇产品的烘焙特性。而天冬酰胺酶和甜菊苷同时添加时可抑制样品中96%丙烯酰胺的生成。动态流变学结果表明：引入天冬酰胺酶不会影响曲奇面团的流变学性质,而甜菊苷的加入会增加面团的弹性模量G＇和黏性模量G〃,这是因为甜菊苷替代面团中糖成分后促进曲奇面团面筋网络的形成。但是,部分糖被取代后会改变曲奇的一些烘焙特性,如：水分含量增加,曲奇饼干颜色变淡,延展率和破碎力降低。感官分析结果表明：感官评定者不能接受45%和60%糖取代量的曲奇,但可以接受15%或30%糖取代量的曲奇。     

壳聚糖对小麦面团流变学特性的影响

研究壳聚糖添加量0、0.4%、0.8%、1.2%、1.6%(w/w)对小麦面团面筋含量、粉质特性、拉伸特性、动态流变特性、质构特性及巯基含量的影响。结果表明,面团流变学各项指标与壳聚糖的添加量有关。随着壳聚糖的添加量增加,湿面筋含量、干面筋含量、面筋持水率增加,而面筋指数下降。同时,面团的形成时间、稳定时间、弹性模量和粘性模量增加。质构仪(TPA)结果表明,面团硬度、咀嚼性增大。当壳聚糖添加量为0.8%时,面团拉伸特性最佳,继续添加反而使拉伸特性降低。巯基含量随壳聚糖添加量增加无显著差异,说明壳聚糖对巯基氧化所需的化学环境并没有造成影响。面团流变学特性变化的原因在于壳聚糖的高持水性和粘附性提升了面团的耐搅拌性,对面筋网络结构有破坏作用。     

复合改良剂对面团流变学特性影响

将硬脂酰乳酸钠(SSL)、瓜尔豆胶、L-抗坏血酸(VC)等改良剂按一定比例直接加入小麦面粉中并混合均匀,通过正交试验分析各种改良剂对面团粉质特性及拉伸特性影响。方差分析结果表明,硬脂酰乳酸钠添加量为0.7%、瓜尔豆胶添加量为0.2%、L-抗坏血酸添加量为0.012%时,面团稳定时间、拉伸力及拉伸面积均显著改善。稳定时间由3.6min提高到11.7min(P＜0.01),拉伸力由102.90g提高到190.96g(P＜0.05),拉伸面积由1884.9g·mm提高到2684.1g·mm(P＜0.05)。复合改良剂加入面粉能很好的改善面团流变学性质。     

抗性淀粉对面粉品质及面团流变学特性影响研究

探讨抗性淀粉对小麦粉流变学特性的影响。分别考察了其对高筋粉、中筋粉的粉质特性、拉伸特性和糊化粘度特性的影响,结果表明,抗性淀粉的添加在一定程度上影响了小麦粉的流变学指标和面粉品质。具体表现为面团稳定时间和粉质评价值降低,弱化度增加,延伸度与拉伸曲线面积降低。抗性淀粉的添加使高筋粉的糊化温程升高,糊化时间延长,对中筋粉的糊化温程和时间影响较小。     

面团改良剂对玉米饺子粉流变学特性影响研究

为改善玉米粉的食用品质,采用添加多种改良剂方法研究其对玉米饺子粉品质的影响.以改性玉米粉与小麦粉混合粉为原料,通过添加谷朊粉、瓜尔豆胶、田菁胶及海藻酸钠等改良剂的单因素试验,对混合粉面团流变学特性的影响规律进行研究.结果表明:谷朊粉可增加面团吸水率,而瓜尔豆胶、田菁胶及海藻酸钠均使面团吸水率降低,同时面团改良剂可使面团...