detection of impurities in mirystyl stearate!!

[Vanessa Cunha Rodrigues]

Hello! I'm from Brazil and i work in a pharmaceutical industry. I wanto to know about methods of determination of impurities in mirystyl stearate: How determinate this impurities and what impurities are presents in this oil. Please, its a urgency, and sorry, my english is too bad.
I have an CG-MS detector Agilent 6890N, please, help me to find a way to discover the impurities of mirystyl stearate or send me sites for my search.

[Consumer Products Guy]

Impurities in this material can include free fatty acids (do titration in hot neutral alcohol with standardized base, or derivatize and do GC or GCMS), free fatty alcohols (GC, GCMS), and fatty alcohol-fatty acid esters from the "other" fatty acid and fatty alcohol chains present, as "all" won't be myristyl alcohol and stearic acid before the esterification; GCMS can identify those as well. Much commercial stearic acid is about 50% palmitic (16) and 50% stearic (18).