Crude Fat, Diethyl Ether Extraction, in Feed, Cereal Grain, and Forage (Randall/Soxtec/Submersion Method): Collaborative Study

TLDR: The proposed submersion method considerably decreases the extraction time required to complete a batch of samples, and the increase in throughput is very desirable in the quest for faster turnaround times and the greater efficiency in the use of labor.

Abstract: A method for determining crude fat in animal feed, cereal grain, and forage (plant tissue) was collaboratively studied Crude fat was extracted from the animal feed, cereal grain, or forage material with diethyl ether by the Randall method, also called the Soxtec method or the submersion method The proposed submersion method considerably decreases the extraction time required to complete a batch of samples The increase in throughput is very desirable in the quest for faster turnaround times and the greater efficiency in the use of labor In addition, this method provides for reclamation of the solvent as a step of the method The submersion method for fat extraction was previously studied for meat and meat products and was accepted as AOAC Official Method 99136 Fourteen blind samples were sent to 12 collaborators in the United States, Sweden, Canada, and Germany The within-laboratory relative standard deviation (repeatability) ranged from 109 to 926% for crude fat Among-laboratory (including within) relative standard deviation (reproducibility) ranged from 10 to 210% The method is recommended for Official First Action