细菌纤维素对大米淀粉凝胶老化的影响

为了解细菌纤维素对淀粉凝胶老化的影响,利用快速黏度分析仪、差示扫描量热仪、X-射线衍射和扫描电镜测定添加不同量细菌纤维素的大米淀粉凝胶糊化特性、热力学特性、结晶性和微观结构。结果表明,随细菌纤维素添加量的增加,大米淀粉糊化时崩解值、回生值、糊化焓值显著降低,显示细菌纤维素抑制了大米淀粉凝胶的短期老化;随细菌纤维素添加量的增加,大米淀粉凝胶老化焓值显著降低,而重结晶从13.26%降至7.93%,说明细菌纤维素抑制了大米淀粉中支链淀粉的重结晶;大米淀粉凝胶微观结构显示细菌纤维素的添加使大米淀粉凝胶的表面更加完整、结构更加致密。由此表明细菌纤维素对大米淀粉凝胶老化具有显著的抑制作用。

Effect of bacterial cellulose on retrogradation of rice starch gel

The effect of bacterial cellulose on the retrogradation of rice starch was investigated by means of rapidvisco-analyzer (RVA), differential scanning calorimetry (DSC), X-ray diffraction(XRD) and scanning electronic microscope (SEM).The results showed that theaddition of bacterial cellulose significantly decreased the breakdown, setback and enthalpy values, which meant that the short-term retrogradation of rice starch was inhibited.DSC results showed clearly that bacterial cellulose significantly reduced the retrogradation enthalpy of amylopectin. XRD results showed that recrystallinity of rice starch was reduced from 13.26% to 7.93% with the addition of bacterial cellulose. SEM of rice starch showed that smaller pore size and a thicker surrounding matrix corresponded with increasing bacterial cellulose concentration. It could be concluded that the addition of bacterial cellulose apparently inhibited the retrogradation of rice starch.