In order to enhance resistant starch (RS) content, and obtain optimal preparation conditions, high-amylose (～70％) corn starch (Hylon Ⅶ) were modified by heat-moisture treatment (HMT), enzymatic treatment, and enzymatic treatment combined with HMT. The resulted highest RS content of three modification methods was 51.5％, 42.5％ and 55.1％, respectively. Enzymatic treatment combined with HMT could increase resistant starch content. The results showed that after three modification methods, the products remained birefringent and granular appearance, and therefore they were granular resistant sfarch (RS2). Compared to native starch, appropriate HMT and enzymatic treatment could obviously increase amylose content. X-ray diffraction indicated that HMT and enzymatic treatment did not change the crystalline type and remained "B" type diffraction pattern. The differential scanning calorimeter pattern showed that the temperatures of the onset, peak, conclusion and enthalpy of gelatinization were increased. HMT and enzymatic treatment could prepare granular resistant starch with thermal stability.%为了提高抗性淀粉含量,并获得抗性淀粉的制备方法和最适工艺参数,该试验采用湿热处理、酶法处理以及酶法协同湿热处理3种方法改性高直链玉米淀粉(Hylon Ⅶ),分别得到抗性淀粉质量分数为51.5%、42.5%和55.1%的产品.异相酶法处理协同湿热处理可使抗性淀粉含量有所提高.淀粉经过3种方法处理后仍保持偏光十字和颗粒形貌,为颗粒型抗性淀粉;与原淀粉相比,适当的湿热处理和酶法处理可使淀粉的直链淀粉含量显著提高;X-射线衍射表明酶解处理和湿热处理没有改变淀粉的晶型,仍为"B"型晶型;差示扫描量热图谱表明抗性淀粉样品的糊化起始温度、峰值温度、终止温度和焓值均升高.湿热处理和酶法处理可制备出热稳定性好的颗粒型抗性淀粉.
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