盐浓度、温度和pH值对NaCl诱导的马铃薯直链淀粉自聚集行为的影响

采用荧光倒置显微镜和红外光谱分别考察不同盐浓度、pH值和温度条件下,马铃薯直链淀粉与NaCl溶液作用不同时间的结晶形貌和化学结构变化,初步探索NaCl诱导的马铃薯直链淀粉自聚集行为。结果表明,NaCl溶液浓度为0.1 mol/L时,室温(25℃)下马铃薯直链淀粉分子最易形成结构有序的聚集体。降低温度至4℃,马铃薯直链淀粉分子不易形成结构有序的聚集体。升高NaCl溶液的pH值至弱碱性(pH 8),马铃薯直链淀粉分子更易形成结构有序的聚集体。

Effects of Salt Concentration,Temperature and pH Value on the NaCl-induced Self-assembly Behavior of Potato Amylose

The NaCl-induced self-assembly behavior of potato amylose as the function of the concentration,pH value and temperature of NaCl solution,was probed by the measurement of fluorescent invert microscope and Fourier transform infrared spectroscopy(FTIR). When the concentration of NaCl solution reached 0.1 mol/L,the organization of double-stranded helices within starch chains into regular assemblies was favored best. Upon decreasing the temperature to 4 ℃,the formation of highly ordered starch assemblies was less promoted in contrast to that at room temperature(25 ℃). The increasing of pH value of NaCl solution to 8(weakly alkaline condition)facilitated the self-assembly of potato amylose.