Dietary fiber is the edible portion of plants or analogous carbohydrates that are resistant to digestion and adsorption
in the human small intestine with complete or partial fermentation in the large intestine (AACC 2001). It includes
polysaccharides, oligosaccharides, and associated plant substances. Dietary fibers promote beneficial physiological
effects including laxation, and blood cholesterol and glucose attenuation (AACC 2001). Some of these materials
may in fact be partially digested in the lower gastrointestinal tract by the microbial flora of the colon. According to
solubility, dietary fiber may be classified as soluble dietary fiber (SDF) or insoluble dietary fiber (IDF), and the soluble
and insoluble fractions together give total dietary fiber (TDF),. Both types are known to be associated with specific
metabolic and physiological functions in human (Roehrig 1988).