soluble fiber definition
soluble fiber. Any dietary fiber that dissolves in water. Soluble fiber is metabolized by bacteria in the gastrointestinal tract into short chain fatty acids, which in turn nourish commensal bacteria in the gut.Examples include most fruit and vegetable fibers, e.g., pectins, barley, cereal grains, cornmeal, and oats.ny dietary fiber that dissolves in water. Soluble fiber is metabolized by bacteria in the gastrointestinal tract into short chain fatty acids, which in turn nourish commensal bacteria in the gut.