Comparative Effects of Particle Size Reduction on Physical Structure and Water Binding Properties of Several Plant Fibers


  • The able assistance of Ms. E. Schwaldt, Medical Surgical Research Unit, University of Alberta, in preparing the scanning electron micrographs is gratefully acknowledged. Many thanks are given to Drs. D. Hadziyev and M.E. Stiles for their helpful comments while conducting this research. Avicel PH101 and Avicel PH105 was supplied by FMC of Canada Limited. The two guar gums were provided by TIC Gums. The author was supported by an Alberta Heritage Foundation for Medical Research (AHFMR) Fellowship during the course of these studies.


Reducing the particle size of AACC wheat bran decreased water-holding capacity, due, in part, to the collapse of its fiber matrix. Physical structure of commercial oat bran collapsed during manufacture and further grinding had limited effect. Physical structure of microcrystalline celluloses and guar gums did not differ between product types. The amount of water held by oat bran and microcrystalline cellulose was increased by reducing particle size. Water binding properties of guar gum were not affected. Physical structure of dietary fiber must be considered if water-binding properties are to be useful predictors of stool bulking efficiency.