Waxy corn starch was chemically modified by esterification (OSA), acetylation (AC), hydroxypropylation(HP), and crosslinking(CL).The effects of these modifications on the nutritionally important starch fractions, namely rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS), were studied in both uncooked and cooked starches. Light transmissivity, resistant sink stability and gelatinization parameters of the native and modified starches were also studied. OSA, HP, and AC increased the light transmissivity, where CL decreased the light transmissivity. The amount of resistant starch (RS) in prime starches were 28.4% ,14%,57.8%and 39.6%in the acetylated, esterified, hydroxypropylated, and cross-linked starches, respectively, whereas the unmodified starch contained 5.7%. By gelatinization, compared with native starches, all the modifications applied tended to decrease the RDS. The highest decrease in RDS was determined after HP treatment. Like the prime starches, the modified starches contained higher contents of undigested starches after gelatinization. The total SDS+RS, the two starch fractions that have nutritional benefits, content of HP and AC starches were notably higher than the OSA and CL starches.% 糯玉米淀粉经过酯化，乙酰化，羟丙基化和交联化学变性后，分别测定生淀粉和糊化淀粉的快速消化淀粉，慢速消化淀粉和抗性淀粉含量以评价其消化性，同时测定其部分理化性质。研究结果表明，除交联淀粉外，其他变性淀粉都具有较高的透明度和抗凝层性。在未糊化的状态下，乙酰化淀粉，辛烯基琥珀酸淀粉，羟丙基淀粉和交联淀粉的抗性淀粉含量分别是28.4%，14%，57.8%和39.6%，而原淀粉仅为5.7%。糊化之后，与原淀粉相比，所有的化学变性淀粉都能减少快速消化淀粉的含量，其中羟丙基淀粉含有最低的快速消化淀粉含量。与生淀粉一样，糊化之后的所有化学变性淀粉都能增加抗性淀粉的含量。其中羟丙基淀粉与乙酰化淀粉，其慢速消化淀粉和抗性淀粉的总量要高于交联淀粉和辛烯基琥珀酸淀粉。
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