On the Possibility of Dietary Fiber Formation by Interaction in the Intestine between Starch and Lipids

Potato starch gels were exposed to monoolein solubilized in bile acid micelles and in the form of a cubic aqueous phase, in order to similate the situation occurring in the intestine. The gels were degraded by pancreatic amylase, and this process was followed by colorimetric determination of dextrose equivalents (DE). A reduction in DE‐values after 1 h of about 20% was observed in the starch gels first exposed to lipids compared to the situation when amylase was added directly to the same starch gel. This difference can be accounted for if it is assumed that the whole amylose fraction forms the helical amylose‐lipid complex, which is relatively stable against enzymatic degradation. The possibilities for such complexing reactions in vivo, corresponding to formation of dietary fiber from pure starch and fat in the food, are discussed.