Muir J G, O'Dea K
Department of Human Nutrition, Deakin University, Geelong, Victoria, Australia.
Am J Clin Nutr. 1993 Apr;57(4):540-6. doi: 10.1093/ajcn/57.4.540.
The aim of the present study was to validate an in vitro assay for quantifying resistant starch (RS) in foods against an in vivo model. The amount of starch escaping digestion in the small intestine of ileostomates was compared with that observed by using the in vitro assay. Subjects with ileostomies were fed five foods containing different types and amounts of RS (baked beans, pearl barley, cornflakes, and whole and ground rice). The total amount of starch escaping digestion and recovered in the effluent (ranging from 5.7% in baked beans to 0.7% in ground rice) was compared with results obtained by using the in vitro assay with an incubation time of 6 h. The assay was found to be a good qualitative predictor (r = 0.90, P < 0.05), but a poor quantitative predictor of RS amounts. Increasing the duration of incubation with alpha-amylase and amyloglucosidase to 15 h resulted in a very close agreement between results from the in vitro technique and the in vivo model. These data indicate that for a variety of foods the in vitro assay produced an excellent estimate of starch escaping digestion in the small intestine of humans.
本研究的目的是针对体内模型验证一种用于定量食品中抗性淀粉（RS）的体外测定方法。将回肠造口者小肠中未被消化的淀粉量与使用体外测定法所观察到的量进行比较。给回肠造口术患者喂食五种含有不同类型和含量抗性淀粉的食物（烤豆、珍珠大麦、玉米片以及糙米和精米）。将未被消化并在流出物中回收的淀粉总量（从烤豆中的5.7%到精米中的0.7%）与使用体外测定法、孵育时间为6小时所获得的结果进行比较。该测定法被发现是一个良好的定性预测指标（r = 0.90，P < 0.05），但对于抗性淀粉含量而言却是一个较差的定量预测指标。将用α -淀粉酶和糖化酶的孵育时间延长至15小时，使得体外技术的结果与体内模型的结果非常接近。这些数据表明，对于多种食物而言，体外测定法能很好地估计人体小肠中未被消化的淀粉量。
