Fatty Acid Content Analysis using GC with Triglyceride Undecanoate Internal Standard

Using triglyceride undecanoate as the internal standard, a mixture of ethanol, water, and the freeze-dried sample was prepared. Sodium hydroxide methanol solution was added and the solution was cooled to reflux. n-heptane and saturated aqueous sodium chloride solution were added, followed by anhydrous sodium sulfate. The upper layer was used for gas chromatographic analysis to calculate the fatty acid content.