双醛蜡质玉米淀粉的制备与特性研究

以蜡质玉米淀粉为原料,高碘酸钠为氧化剂,通过单因素实验,得到双醛淀粉制备的最优工艺条件:高碘酸钠与淀粉物质的量之比1.1:1,反应pH3.0,温度30℃,反应时间2h,淀粉乳浓度8%,得到的双醛淀粉中醛基含量为87.36%。偏光显微镜图片显示,样品醛基含量越高,偏光十字越少;通过红外图谱的表征,发现在波长为1729cm-1处出现明显的吸收峰,说明反应产物中有醛基存在;布拉班德粘度曲线表明,双醛淀粉的起糊温度比原淀粉高,峰值粘度随氧化度的升高而降低;X-射线衍射图谱表明,强峰吸收随着醛基含量的升高而消失,说明淀粉的结晶结构被破坏。

Study on preparation and properties of dialdehyde starch from waxy corn starch

The dialdehyde starch was prepared through oxidation reaction with waxy corn starch and sodium periodate as raw material and oxidant respectively.By the experiments of single factor,the optimal conditions of process were as follows:the ratio of sodium periodates and starch was 1.1:1,the pH of the reaction was 3.0,the temperature was 30℃,the reaction time was 2 hours,and the concentration of starch slurry was 8%,the aldehyde content of prepared sample could reach 87.36%.From the photos of polarizing microscope,the polarizing cross reduced with the increase of aldehyde content in dialdehyde starch;through the characterization of infrared spectrum,absorption peak appeared around the wave of 1729cm-1 obviously,demonstrating the existence of aldehyde content.And the Brabenderviscosity curves appeared:comparing with the native starch,the initial gelatinization points lagged behind and the peak viscosities which were lower than native starch went up with the increase of aldehyde content;X-diffraction spectrum appeared that strong peak absorption gradually disappeared with the increase of aldehyde content.