Hydroxypropyl-Distarch Phosphate from Potato Starch Increases Fecal Output, but Does Not Reduce Zinc, Iron, Calcium, and Magnesium Absorption in Rats

The physiological effects of hydroxypropyl‐distarch phosphate (HDP) were examined in rats. Male rats were fed a fiber‐free purified diet containing gelatinized potato starch (PS, 50 g/kg diet) that was not modified chemically or gelatinized, chemically modified potato starch (CMS, 50 g/kg diet) for 21 d. PS was used as the control. Six kinds of gelatinized HDP from potato with 2 different degrees of hydroxypropylation and 3 different degrees of cross‐linking were used as CMS. The wet weight and moisture of the fecal output of the rats fed highly hydroxypropylated HDP was 70% and 30% greater, respectively, than that in the control rats. The weights of the cecal wall and content of the rats fed highly hydroxypropylated HDP were 15% and 30% higher, respectively, than those of the control rats. The apparent absorption of Mg was 15% higher in the rats fed highly hydroxypropylated HDP than in the control rats. On the other hand, the apparent absorptions of Ca, Zn, and Fe were not affected by the diet. Cross‐linking did not influence the above‐mentioned physiological effects of HDP. Fecal excretion of bile acids and the plasma cholesterol concentration were not affected by the diet. These results show that the physiological effects of HDP depend on the hydroxypropylation but not the cross‐linking.