Effects of Maillard's reaction products on apparent mineral absorption in different parts of the digestive tract. The role of microflora.

1.5 and 3% of Maillard's reaction products (MRP), prepared by heating glycine and glucose, were incorporated ino a semi-synthetic diet. The diet was sterilized by irradiation. MRP caused a change in apparent absorption of calcium and magnesium in germfree (GF) and conventional (CV) rats. The absorption of these minerals was reduced in the small intestine of CV and GF, perhaps due to the action of MRP on enterocyte metabolism. This effect was compensated for only in CV rats by increased absorption of these minerals in the cecum and the colon. The presence of microflora and the increase in cecal volume in CV rats suggested that MRP fermentation increased mineral absorption in the cecum and colon. However, although total apparent absorption of magnesium and phosphorus was higher in CV rats ingesting MRP, the urinary excretion of these minerals was also higher and their retention was not better. The effect of MRP in GF rats was not compensated for in the cecum, and mineral retention was significantly reduced in GF rats ingesting MRP.