Relationships among crude fiber, neutral detergent fiber, in vitro dietary fiber, and in vivo (rats) dietary fiber in wheat foods.

: The in vivo dietary fiber contents of wheat milling fractions and wheat foods, determined in rat feeding experiments, were compared with dietary fiber values determined in vitro with pronase alpha-amylase digestion. Both types of dietary fiber values were compared with crude fiber and neutral detergent fiber values in the same materials. Regression analyses indicated close correlation amongst all values determined. It appears that laboratory analysis for crude fiber, neutral detergent fiber, or in vitro dietary fiber accurately predicts in vivo dietary fiber (rats) for wheat milling fractions when the laboratory result is adjusted by means of an appropriate regression equation.