不同直链含量玉米淀粉结晶结构及其消化性研究

Crystalline Structures and Digestibility of Cornstarches with Different Amylose/Amylopectin Content

对4种不同直链/支链淀粉含量玉米淀粉的结晶结构和形态学进行研究,并采用Englyst法对4种淀粉进行体外消化模拟试验,探索了淀粉结构与消化性质的关系。高支(蜡质和普通)和高链(HylonⅤ和HylonⅦ)玉米淀粉分别属于A型和B型结晶结构,其消化机理对应为"由内向外(inside-out)"和"由外向内(exo-pitting)"消化类型。高支玉米的慢消化淀粉(SDS)含量较高,而高链玉米淀粉的抗性淀粉(RS)含量远高于高支淀粉。

Crystalline structures and morphology of four different cornstarches with different amylose/amylopectin content were investigated. The vitro digestibility of four cornstarches was tested according to Englyst method. The relationship between starch structure and digestion mechanism was discussed. High-amylopeetin （waxy and normal） and high-amylose （Hylon Ⅴ and Hylon Ⅶ cornstarches belong to A-and B-type structures, respectively. A-type starches are ＂inside-out＂ digestion mechanism, while the B-type starches produce a different hydrolysis pattern observed as ＂ exo-pitting＂. The level of slow digestion in high amylopectin cornstarch was higher than high-amylose cornstarch, while the Resistant Starch （RS） content of high-amylose cornstarches is much higher than high amylopection conrstarch.