Crude Fiber


Crude Fiber



This procedure is used for the determination of crude fiber (CF) in animal feed and pet food using the Weende method (AOAC method 978.10). Using sequential acid and alkali extractions, this method predominantly removes protein, sugar, starch, lipids, and portions of both structural carbohydrates and lignin. Digestion with a sulfuric acid solution extracts sugar and starch. A second alkaline digestion using a sodium hydroxide solution removes proteins and some hemicellulose and lignin. Crude fiber is determined gravimetrically as the residue remaining after the acid and alkaline digestions. The method has a detection limit of 0.5%.

Sample amount requested: 10 g (Sample particles cannot be less than 1mm — that is, 18 mesh sieve.)

Questions concerning limited sample size can be answered by the UC Davis Analytical Laboratory.

AOAC Official Method 978.10, Fiber (Crude) in Animal Feed and Pet Food, Official Methods of Analysis of AOAC International, 18th edition (2005), Chapter 4, pp. 46-47, AOAC International, Gaithersburg, MD.