Dried sample is exhaustively extracted by Soxhlet or continuous (Goldfisch) extraction, utilizing petroleum ether as solvent. Solvent is evaporated, and residue is dried to constant weight at 100°. Residue is expressed as % crude fat or ether extract. This method is applicable to flours of grains (wheat, corn, soybean, etc.) and mixed feeds that have not been heat-treated, baked, or expanded.