In addition to food manufacturers, epidemiologists, scientists and dieticians need data on the fiber content of foods (8). However, attempts to define and standardize methods for measuring dietary fiber remain controversial. Dietary fiber is essentially made up of undigested carbohydrates present in the diet (9). These carbohydrates can ferment in the large intestine, although some tough fibers, such as purified cellulose, escape any fermentation, while other fibers, such as inulin or pectin, are completely degraded by bacteria in the colon. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay Most analytical schemes for measuring dietary fiber are chemical and enzymatic extraction procedures. The TDF method, or Prosky method, has become the standard method for measuring dietary fiber in the United States. Because the TDF method does not isolate all undigested carbohydrates, especially short-chain oligosaccharides, other methods for quantifying these compounds have been developed and accepted. Determining fiber solubility was an attempt to relate physiological effects to chemical types of fiber (9). Soluble fiber was thought to have beneficial effects on serum lipids, while insoluble fiber was linked to laxative benefits. This division between soluble and insoluble fiber is still used in nutrition labeling. However, despite these commonly used generalizations, the scientific evidence supporting that soluble fiber lowers cholesterol and insoluble fiber increases stool weight is inconsistent. Many sources of fiber are mostly soluble but still increase stool weight, such as oat bran and psyllium. Additionally, soluble fibers like inulin do not lower blood lipids. Most fruits and vegetables are concentrated in insoluble fiber, not soluble fiber. Exceptions to this generalization include cooked potatoes, oranges, and grapefruits. The USDA nutrient database includes only total fiber; There are no official databases that include soluble and insoluble fiber. The total, insoluble, and soluble fiber content lists are compilations of data from the USDA, published literature, and estimated values ​​(10). Often, values ​​for soluble and insoluble fiber do not add to total fiber, or values ​​for soluble fiber have been estimated by subtracting a literature-reported value for insoluble fiber from a USDA value for total fiber. Not surprisingly, there is a lot of discrepancy in fiber concentrations for fruits and vegetables. Please note: this is just an example. Get a custom paper from our expert writers now. Get a Custom Essay Processing can increase or decrease the fiber content of a fruit or vegetable. Peeling fruits or vegetables will reduce the fiber content (11). A serving of grapefruit without an associated membrane contains much less fiber than a serving of grapefruit with membranes (0.4 vs. 1.4 g/serving). Home cooking generally has a negligible effect on fiber content. Cooking, in general, can even increase the fiber content of a product if water is removed during the cooking process. Cooking or other heat treatments (e.g., extrusion) used in food processing will also increase the fiber content of the product, concentrating the fiber by removing water or producing Maillard products that are captured as fiber by gravimetric methods. Fruit juices are not devoid of fiber.