Quantitative isolation of lipids of partially defatted and whole peanuts by a dry column method

A dry column method of lipid extraction was found to be applicable to peanuts—partially defatted as well as whole. Total lipid was obtained from the peanut/sodium sulfate/Celite 545 columns by isocratic elution with dichloromethane/methanol 9:1. Moreover, neutral lipids were obtained by sequential elution that were completely free from polar lipids. First, dichloromethane eluted the neutral lipids, then the 9:1 solvent eluted the polar lipids—at times containing small quantities of neutral lipids. Total lipid values obtained by the column extraction method were slightly higher than those obtained by the standard Soxhlet extraction procedure. This was due in part to the more complete polar lipid isolation produced by the column method. In partially defatted peanuts produced by mechanical pressing, 99% of the polar lipids remained in the retained oil, and these were shown to be slightly less unsaturated than the neutral lipids.