Ethyl Acetate/Ethyl Alcohol Mixtures as an Alternative to Folch Reagent for Extracting Animal Lipids

The lipids of fresh egg yolk, boiled yolk, yolk powder, and raw animal tissues including pork loin, belly pork, and pork fat were extracted with the mixed solvents composed of ethyl acetate (EtOAc) and ethyl alcohol (EtOH) at 2:1 and 1:1 volume ratios, and the results were compared with those obtained with Folch reagent, that is, a mixture of chloroform and methyl alcohol (2:1, v/v). Extraction yields, lipid profiles, and fatty acid compositions were determined by weighing, TLC-FID, and GC, respectively. Data of the extracts obtained with the mixtures of EtOAc and EtOH were not significantly different from those obtained with Folch reagent, implying that the mixed solvent composed of EtOAc and EtOH (1:1 to 2:1, v/v) may replace Folch reagent, which is considered to be toxic and mutagenetic due to its component of CHCl3, for lipid extraction. Keywords: Folch reagent; ethyl acetate; ethyl alcohol; egg yolk; animal tissues