Dietary Fiber, Lignocellulose and Hemicellulose Contents of Selected Foods Determined by Modified and Unmodified Van Soest Procedures

Neutral detergent residues (NDR) of 6 vegetables, 3 fruits, and 3 grain products were determined by the unmodified Van Soest ND procedure and by modifications which incorporated starch‐or protein‐hydrolyzing enzymes. Modification of the procedure significantly lowered NDR weights of several foods, with the greatest effect on grain products and high starch vegetables. Incubation with B. subtilis amylase and pancreatin (1 hr) yielded NDR which generally were not different from those incubated with hog amylase (18 hr). Modification of the procedure had little effect on lignocellulose values, determined by treating NDR with acid detergent solution, and more effect on hemicellulose values. Results suggest that amylase treatment, but not a long incubation, may be necessary for some foods.