Determination of oil and lipids in cottonseed meal

Two simple methods for determining total oil equivalent in cottonseed meal are described. The meal is extracted with methanol, and the crude extract is either (a) saponified and subsequently acidified to find the weight of acids set free, or (b) subjected to methanolysis to determine the weight of esters formed. When applied to a meal previously extracted with petroleum ether, these methods determine lipids. Results obtained on three commercial cottonseed meals were in excellent agreement with those obtained by the more cumbersome method requiring direct saponification of the ground meal. The methods described should also be applicable to soybean and sunflower seed meals and to other systems containing lipids, such as flours, doughs, and leaf proteins. One of the methods is particularly useful as a preliminary step in the determination of cyclopropenoid acids in cottonseed meal because much larger lated as methyl esters.