Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea.
Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea.
Int J Biol Macromol. 2020 May 15;151:1049-1057. doi: 10.1016/j.ijbiomac.2019.10.146. Epub 2019 Nov 15.
The objectives of this study were to optimize the conditions for the preparation of sweet potato starch containing a high proportion of slowly digestible starch (SDS) by heat-moisture treatment (HMT), and to investigate the structural properties of SDS and resistant starch (RS) fractions isolated from this modified starch. Response surface methodology evaluation of considering temperature, time, and moisture content was conducted to determine the HMT condition for maximizing SDS yield. Maximum SDS content (50.9%) was obtained after 8.6 h at 113 °C with 22.8% moisture level. Scanning electron micrographs of RS fractions displayed growth ring structure and hollow regions. X-ray diffraction patterns of SDS + RS and RS fractions were not changed by HMT. Gelatinization enthalpy of the SDS + RS fraction was decreased more than that of the RS fraction. The results indicated that the SDS fraction consisted of less perfect crystallites and amorphous regions, whereas the RS fraction was composed mostly of crystalline regions.
本研究旨在通过湿热处理（HMT）优化制备高比例慢消化淀粉（SDS）的甘薯淀粉的条件，并研究从这种改性淀粉中分离出的 SDS 和抗性淀粉（RS）的结构特性。通过响应面法评价考虑温度、时间和水分含量来确定 HMT 条件，以最大限度地提高 SDS 产量。在 113°C 下加热 8.6 小时并保持 22.8%的水分水平可获得最大 SDS 含量（50.9%）。RS 级分的扫描电子显微镜照片显示出生长环结构和中空区域。X 射线衍射图谱表明 SDS+RS 和 RS 级分的结构未因 HMT 而发生变化。SDS+RS 级分的凝胶化焓降低幅度大于 RS 级分。结果表明，SDS 级分由较少的完美结晶区和非晶区组成，而 RS 级分主要由结晶区组成。
