Cottonseed meal | Feedipedia

Mechanical extraction: this traditional method of cottonseed oil extraction uses a circular mortar (called ghani in India, Achaya, 1993) or more advanced technology, such as a hydraulic press or a screw press (expeller). The cotton seeds may be dehulled, cracked, dried or heated before being fed to the press. The resulting cake is dried, ground and then processed into large pellets (Ash, 1992). Mechanical extraction is not very efficient and up to 20% of the seed oil may remain in the pressed cake, depending on the technology used (O'Brien et al., 2005). Direct solvent extraction process: as in mechanical extraction, the seeds may be dehulled, cooked, cracked and flaked, but the oil is extracted by solvent (usually hexane) alone. The extracted cake is heated to eliminate the solvent and then generally ground into meal (Ash, 1992). This method was widely used in the 1980s in the USA (Morgan, 1989). Pre-press solvent extraction: this method combines a mechanical extraction (screw press or expander) step, which reduces the oil by one-half to two-thirds of its original level, and a solvent extraction, which results in a 97% oil extraction rate. The dehulled, cracked, dried, heated or flaked cotton seeds are first screw-pressed or expanded and the pressed flakes or pellets are then solvent-extracted.