Concept of Dietary Fiber
Although no consensus in the scientific community about the concept of dietary fiber, can be defined as that portion of the edible plants that resists digestion and absorption in the human small intestine and undergoes a partial or complete fermentation in the large intestine. This plant part is formed by a group of chemical compounds of diverse nature (polysaccharides, oligosaccharides, lignin and similar substances [1]). From a nutritional standpoint, and strictly speaking, the fiber is not a nutrient, since it is not directly involved in basic metabolic processes in the body. However, dietary fiber plays a physiological function to stimulate intestinal peristalsis. The reason why the human body can not process it is because the digestive tract lacks the enzymes that can hydrolyze. This does not mean that the fiber passes intact through the digestive system: although the bowel does not have enzymes to digest the enzymes of the bacterial flora partially fermented fiber and break down into various chemicals: gases (hydrogen, carbon dioxide and methane) and short chain fatty acids (acetate, propionate and butyrate). The latter can play an important role in the body of living beings. Dietary fiber is found in foods of plant origin little technological processes, such as cereals, fruits, vegetables and legumes.