本文研究了高压均质压力对淮山药淀粉颗粒形貌、偏光十字、粒径、结晶特性和体外模拟消化性的影响。研究结果表明：经高压均质处理后，淮山药淀粉颗粒表面破损明显，偏光十字强度减弱；淀粉粒径随均质压力的升高呈现先减小后增大的趋势，最小粒径为25.16 μm（压力为40 MPa时）,最大粒径为27.81 μm（压力为100 MPa时）;淀粉颗粒的结晶类型保持不变、仍为C型，淀粉结晶度从26.45%下降到21.00%；红外吸收光谱中3233.42、1164.01、1081.90、1050.27和1015.81 cm-1处的吸收峰变窄、强度变低，淀粉的有序程度降低。原淀粉中快速消化淀粉（RDS）、慢消化淀粉（SDS）和抗性淀粉（RS）含量分别为11.32%、7.00%和81.68%，经过100 MPa均质处理之后，RDS和SDS含量分别增加至20.63%和10.41%，RS含量则减少到68.96%。这说明高压均质处理能降低淀粉内部的结晶度，使得抗酶解能力降低，淀粉消化性提高，且压力越高，这种趋势越明显。

The effect of the pressure from high-pressure homogenization on granule morphology, polarization cross, grain diameter, crystal property and in vitro digestibility of Dioscorea opposita starch were investigated in this study. The results showed that the surface of Dioscorea opposita starch granule was damaged and the intensity of polarization cross was reduced by high-pressure homogenization. The particle size decreased initially and increased subsequently with increasing homogenization pressure. The minimum (25.16 μm) and maximum sizes (27.81 μm) were found at pressures of 40 MPa and 100 MPa, respectively. The C-type crystal structure was not changed, while the degree of crystallinity decreased from 26.45% to 21.00%. The widths and intensities of the infrared (IR) absorption peaks at 3233.42, 1164.01, 1081.90, 1050.27, and 1015.81 cm-1 decreased. The degree of order in the starch was also reduced to some extent. The contents of rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) in the native starch were 11.32%, 7.00%, and 81.68%, respectively. After the homogenization treatment at 100 MPa, the contents of RDS and SDS were increased to 20.63% and 10.41%, respectively, while the RS content was reduced to 68.96%. The results suggested that high-pressure homogenization reduced the degree of crystallinity in the starch, which results in reduced resistance to enzymatic digestion and enhanced digestibility. This trend was more apparent at higher pressure.

福建省高等学校科技创新团队支持计划（闽教科[2012]03号）；福建农林大学科技创新团队支持计划（cxtd12009）