[M+54]+- based APCACI-MS/MS spectra of m/z 909 from (A) (16:0/9,11-18:2/9,11-18:2)-TAG, (B) (16:0/10,12-18:2/10,12-18:2)-TAG and (C) (16:0/9,12-18:2/9,12-18:2)-TAG. Cleavages directly before the first double bond and immediately after the second, as shown in the structures, give rise to diagnostic ions.