Rapid quantitative determination by 13C NMR of the composition of acetylglycerol mixtures as byproduct in biodiesel synthesis

► Commercial mono- and diacetin are mixtures of partly acetylated glycerols. ► 1H NMR spectra presents signal overlapping for these components. ► By 31P NMR spectroscopy triacetin may not be identified and quantified. ► 13C NMR allows the quantification of all the components in commercial mixtures. ► 13C NMR results were validated with GC and HPLC-ELSD.