Abstract:A internal standard method to determine cis- and trans- fatty acids in formula powders by gas chromatography was developed. Samples were methylesterized with acetyl chloride-MeOH，and analyzed by GC on a HP-88 column with FID as detector and triundecanoin as the internal standard. The results showed that cis- and trans- fatty acids in formula powders were well separated by this method. The recoveries, relative standard deviation and the detection limit of the GC method were 97.2%~104.6%, less than 3.5% and 5 μg/g, respectively.
