【作者】 杜双奎；

【导师】 李志西；

【作者基本信息】 西北农林科技大学 ， 食品科学， 2001， 硕士

【摘要】 本研究以强筋粉、中筋粉为对照，对商品荞粉、荞麦心粉、荞麦全粉、荞麦麸粉、苦荞全粉、苦荞麸粉等荞麦粉的理化特性进行了系统测定，参照国际标准分析方法，对荞麦混粉的粉质特性、拉伸特性、糊化粘度特性、面包焙烤特性进行了系统分析。试验结果表明：荞麦粉的水分含量小于对照小麦粉。不同部位的荞麦粉，其粗蛋白含量、粗淀粉含量、芦丁含量差异较大。荞麦粉的灰分含量、祖纤维含量一般高于小麦粉。荞麦粉中淀粉酶活性显著低于小麦粉。荞麦粉的持水力明显大于小麦粉。荞麦粉的降落数值远大于小麦粉(＞1000s)。荞麦粉的沉淀值显著小于小麦粉。同小麦粉相比，荞麦粉中富含精氨酸、赖氨酸利天冬氨酸。荞麦混粉的芦丁含量、赖氨酸含量随着荞麦粉比例的增大呈线性增加。 混粉粉质特性分析表明对于不同小麦粉，混合不同的荞麦粉，其粉质参数变化复杂。荞麦粉在混粉中的比例小于30％时，混粉面团主要表现出基粉小麦粉的面团特性，尚可用Brabender粉质仪来评价其粉质特性；荞麦粉比例大于50％后，混粉面团已完全失去小麦粉的面团特性，再用粉质仪按常规方法来评价混粉的粉质特性，已失去实际意义。 荞麦混粉面团的拉伸特性随着混粉中荞麦粉比例的增大而变差，混粉面团的韧性增强，延伸性减弱，韧性与延伸性的平衡性能下降，面团筋力降低。适当改变面团的揉制时间和静置时间，增加揉制次数和静置次数，可以增强荞麦混粉面团的延伸性，降低面团张力，改善韧性与延伸性的平衡性，从而使得面团的加工性能增强。 荞麦粉与小麦粉相比，一般具有较高的峰粘度、热粘稳定性、起糊温度、最终粘度和回生值。随着混粉中荞麦粉比例的增大，荞麦混粉的峰粘度、保持强度、最终粘度、回生值、起糊温度均呈增大趋势；而粘度衰减度呈下降趋势；混粉峰值时间变化规律不明显。 荞麦粉的添加对混粉面包的质量有影响。荞麦粉比例为10％和20％时，荞麦混粉尚具有较好的焙烤特性，面包的体积、比容与中筋粉相当，均小于强筋粉面包，贮存间面包硬度变化幅度与中筋粉一致，具有相同的老化速率，均稍大于强筋粉；荞麦粉比例为30％时，荞麦混粉的焙烤特性较差，面包的体积、比容显著小于强筋粉面包，面包硬度明显大于对照强筋粉和中筋粉，贮存期间的硬度变化幅度显著高于强筋粉面包和其他配比的混粉面包，在3-26h内混粉面包的老化速率最快。相同比例下的混粉，荞麦心粉混粉的焙烤特性较好，面包硬度低于商品荞粉，贮存间的老化速率小于商品荞粉。荞麦粉比例大于30％，荞麦混粉难以制作面包。更多还原

【Abstract】 The physicochemical properties of various buckwheat flours and wheat flours(as control) were determined and the technological properties of the mixture flours made from buckwheat and wheat were studied systematically with the international standard methods. The experimental results were showed as followings:Compared with wheat flour, buckwheat flours have lower moisture, higher ash and crude fiber content. Different milling fractions have significant difference in content of crude protein, crude starch, rutin . Amylase-activity in buckwheat flour was much lower than that in wheat flour. Water-binding capacity and falling number of buckwheat flour were obviously higher than those of wheat flour. However, sedimentation value of buckwheat flour was lower. As compared with wheat flour, buckwheat flour was rich in Lys, Arg and Asp. The amounts of rutin and Lys in mixture were increasing continuous with the increase of buckwheat flour.The mixture dough has also acted as the wheat dough properties as buckwheat flour content was below 30%. However, as increased above 50%, the mixing dough has never showed the wheat dough properties. When analyzed by Brabender Farinograph, the result was very complicity and has no practice value.As the amount of buckwheat flour in the blends increased, extension properties of mixing dough was weak, dough tenacity strengthened, dough spreading capacity decreased, the balance between tenacity and extension poor. By adjusting kneading (dough-mixed) time and relaxation time, the mixing dough process properties would be improved.A comparison of pasting characteristics of buckwheat flour to those of wheat flour indicated that buckwheat flour has higher peak viscosity, hot viscosity stability, pasting temperature. finial viscosity, setback and lower viscosity breakdown. As buckwheat flour increasing, peak viscosity, holding strength, finial viscosity, setback and pasting temperature of mixing flour were increased and holding strength was declined. The change of peak time was not obvious.Buckwheat flour has effect on the quality of bread. The mixing flour has good baking properties at 10% and 20% buckwheat flour. Loaf volume, specific volume and hardness, setback speed of bread with 1 0%and 20% buckwheat flour were similar to bread from100% common flour. But the property of bread containing buckwheat flour was prior to those of strong wheat bread. With 30% buckwheat flour or more, the mixing flour baking properties were not good, the volume and specific volume of bread were significantly lower than those of strong flour bread. Hardness and setback speed of bread containing 30% buckwheat flour were much higher than those of strong bread during staling. Setback speed of the bread with 30% buckwheat flour was the fastest during 3-26h. As buckwheat flour content was above 30%, the mixing dough was very difficult to deal with during the bread-making process.更多还原