燕麦全麦粉中淀粉消化性的研究

Oat Starch Digestibility in Whole Oat Flour

摘要:

研究了燕麦β-葡聚糖以及蛋白质对燕麦全麦粉中淀粉消化特性的影响，并对这一影响可能存在的机理进行了探索。燕麦通过磨粉，过筛后，按照颗粒大小分级成了不同的燕麦粉样品。检测表明，不同颗粒大小级别的燕麦粉具有不同质量分数的β-葡聚糖和蛋白质，不同的糊化特性，燕麦的消化速度则随着颗粒的增大而减小。蛋白酶预处理燕麦全粉提高了淀粉的水解速率，但外加β-葡聚糖到消化液中并没有对淀粉原有的消化特性产生显著影响。共聚焦显微镜结果显示，燕麦粉中蛋白质、β-葡聚糖和淀粉可能共同形成了一种聚合结构。因此，燕麦粉固有的β-葡聚糖可能与其他成分，如蛋白质交联而形成一定的空间结构，降低了消化酶与淀粉的接触度，从而延缓了燕麦粉中淀粉的消化。

Abstract:

The effect of oat beta- glucan and protein on oat starch digestion and related mechanism were studied in this paper. Methods：Oats grain was processed into flour and then，sieved into whole oat flour samples with different particle sizes which contain different amounts of β-glucan（O-glu） and protein，and an in vitro starch digestion assay revealed different starch digestibility among those flour samples. RVA analysis also showed different profiles，and the addition of β-glucan did not significantly affect the starch digestion while pretreatment with protease increased the rate of starch digestion. Confocal microscopy analysis showed some complexed structure formed among β-glucan，protein and starch. Thus，it seems that the effect of β-glucan on starch digestion needs certain structural forms that are natively present in oat flour，and a matrix structure formed by linking with other components such as protein，might be the basis for slow digestion property of starch in the whole oat flour.