马铃薯抗性淀粉的微波-湿热制备工艺优化及结构表征

Optimization of Preparation Technology of Potato Resistant Starch by Microwave Heat-Moisture Treatment and Its Structure Characterization

以马铃薯淀粉为原料,采用微波-湿热法制备马铃薯抗性淀粉。考察了淀粉乳质量分数、微波功率、微波时间对马铃薯抗性淀粉得率及结构的影响。结果表明,在微波时间240 s、微波功率750 W、淀粉乳质量分数15%条件下,马铃薯抗性淀粉的最大得率为9.77%。通过扫描电镜、红外光谱、X-射线衍射分析表明,马铃薯淀粉颗粒完整性被破坏,结晶结构改变,结晶度增加;马铃薯淀粉经微波-湿热处理后,未有新的官能团产生,但分子间氢键发生变化。

In this research, potato resistant starch was prepared from potato starch with method of microwave heat-moisture treatment.The effects of starch milk mass fraction, microwave power and microwave time on yield and structure of potato resistant starch were investigated. The maximum yield of potato resistant starch was 9.77% with the optimal conditions of microwave time 240 s, microwave power 750 W and starch milk mass fraction 15%.The results of scanning electron microscope （SEM）, Fourier transform infrared spectrometer（FT-IR） and X-ray diffraction （XRD）indicated that the structural integrity of starch granules was destroyed, while the crystal structure was changed and the degree of crystallinity was increased. New functional groups were not formed from the sample prepared with microwave heat- moisture treatment method, but the intermolecular hydrogen bonds were altered.