【作者】 刘敏；

【导师】 韩育梅；

【作者基本信息】 内蒙古农业大学 ， 农产品加工与贮藏工程， 2018， 硕士

【摘要】 抗性淀粉RS₃（Resistant StarchШ）具有良好的加工性能及生理特性,在食品加工应用中的前景广阔。近年来,针对RS₃制备工艺的改进研究较多,但关于不同制备方法对抗性淀粉结构、性质影响的报道较少。本研究分别采用微波-双酶法、湿热-酶法、微波-湿热法、2次循环湿热法制备马铃薯抗性淀粉,探讨抗性淀粉在聚集态结构和链结构方面的变化及其性质的差异。在此基础上,分析抗性淀粉结构与其性质的相关性。结果如下:（1）制备方法对抗性淀粉聚集态结构及链结构的影响抗性淀粉的颗粒完整性被破坏,表面粗糙且存在明显的层状起伏,多为不规则的碎石状,直径约为8³0μm,微波-双酶、湿热-酶及2次循环湿热抗性淀粉的表面可以观察到较为明显的凹陷孔洞和蜂窝状结构。抗性淀粉的双折射模式都已消失,都为C-型晶体结构,结晶度均较原淀粉增加。抗性淀粉与原淀粉的官能团相似,但其有序程度(R_1047/1022)增大。微波-双酶抗性淀粉重均分子量（Mw）高于原淀粉,且分子量分布较为均匀;另外三种抗性淀粉重均分子量（Mw）均低于原淀粉且分子量分布不均匀。（2）制备方法对抗性淀粉性质的影响抗性淀粉的得率都较原淀粉有显著提高;2次循环湿热抗性淀粉的溶解度优于其他三种抗性淀粉,湿热-酶抗性淀粉的溶解度最差;膨润度呈现相反的结果。紫外-可见吸收光谱证实抗性淀粉都是直链与支链淀粉构成的混合物。微波-双酶、湿热-酶抗性淀粉的峰值黏度、谷值黏度、最终黏度、崩解值均低于原淀粉。抗性淀粉都为非牛顿流体,微波-湿热、2次循环湿热抗性淀粉表现出剪切稀化现象,微波-双酶、湿热-酶抗性淀粉表现出剪切增稠行为;动态流变学结果表明抗性淀粉均为弱凝胶,都表现出弹性行为。抗性淀粉的T_o、T_p、T_c均高于原淀粉,微波-双酶、湿热-酶抗性淀粉的ΔH值增大,微波-湿热、2次循环湿热抗性淀粉的ΔH值减小。（3）抗性淀粉结构与性质的相关性分析抗性淀粉的结晶度、颗粒有序化程度及分子量对物理性质、糊化性能、流变学性质、热力学性质存在显著性影响。抗性淀粉的结晶度与分子量越大,颗粒有序程度越高,则得率越大,膨润度越好,抗性淀粉流体性质的稠度增大,形变能力增强,但却不易被糊化,且糊化时的粘度增加,回升值、崩解值增大。更多还原

【Abstract】 RS3(Resistant Starch Ⅲ)has good processing performance and physiological characteristics,which is widely used in food processing.There are many studies on improvement of the prepared methods of RS3 in recent years.However,there are few reports on the effects of the structures and properties of resistant starch caused by different prepared methods.Potato resistant starches are prepared by microwave dual-enzymatic treatment,heat-moisture enzymatic treatment,microwave heat-moisture treatment and dual autoclaving-retrogradation treatment in this study.The aggregate state structure and chain structure of resistant starch are analyzed,and the differences of properties for resistant starch are investigated.On the basis of these studies of resistant starches prepared with different methods,relationship between structures and properties are concluded by correlation analysis.The results are as follows:(1)Effects of prepared methods on the aggregate state structure and chain structure of resistant starch are studied.The granule morphology of resistant starch is destroyed,which the surface is rough and obvious layered fluctuations are found.The shape of resistant starches is similar as irregular gravels,which diameter is about 8-30μm.The resistant starches prepared with microwave dual-enzymatic treatment,heat-moisture enzymatic treatment and dual autoclaving-retrogradation treatment can observe significant holes and recesses of the honeycomb structure.The birefringence patterns of resistant starches have all disappeared.They are C-type crystal structures,and the degree of crystallinities are increased compared to the original starch.Fourier transform infrared spectroscopy shows that functional groups of starch and resistant starches are similar,but their ratio of intensity(R1047/1022)is increased.The weight-average molecular weight(Mw)of resistant starches prepared with microwave dual-enzymatic treatment is higher than that of potato starch,and its molecular weight distribution was relatively uniform.But the weight-average molecular weight(Mw)of resistant starches prepared with the other three treatments is lower than that of the original starch,and their distribution of the molecular weight of the other three resistant starches is not uniform.(2)Effects of prepared methods on properties of resistant starches are studied.The yields of resistant starch are significantly higher than that of the original starch.During the range of 50～90 0C,solubilities of resistant starches prepared with dual autoclaving-retrogradation treatment are superior to those of the other three resistant starches,in which microwave dual-enzymatic treatment has the worst solubility.While the swelling power shows the opposite result.UV-visible absorption spectroscopy confirms that the resistant starches are a complex of amylose and amylopectin.The peak viscosity,trough viscosity,final viscosity and breakdown of resistant starches prepared with microwave dual-enzymatic treatment and heat-moisture enzymatic treatment are all higher than those of original starch.The resistant starches are non-Newtonian fluids.Resistant starches of microwave heat-moisture treatment and dual autoclaving-retrogradation treatment show shear-thinning behavior,but resistant starches prepared with microwave dual-enzymatic treatment and heat-moisture enzymatic treatment are shear thickening fluids.The oscillatory experiments show resistant starches are weak gel behavior and all of them exhibited elastic behavior.The To,Tp,and Tc of resistant starches are higher than those of potato starch.The enthalpy value of resistant starches prepared with microwave dual-enzymatic treatment and heat-moisture enzymatic treatment are increased,while resistant starches prepared with microwave heat-moisture treatment and dual autoclaving-retrogradation treatment are decreased.(3)Correlation analysis of structures and properties of resistant starch are studied.Structural parameters of crystallinity,ordering degree and molecular weight of resistant starches have significant effects on physical properties,gelatinization properties,rheological properties and thermal properties.The higher crystallinity,molecular weight and ordering degree of resistant starches,the better of the yield and swelling power.And the fluid properties of resistant starches increase consistency index and deformation ability.During the gelatinization of resistant starches,the viscosity,breakdown and setback are increasing,but it is not easy to be gelatinized.更多还原