Triacylglycerol regioisomers in human milk resolved with an algorithmic novel electrospray ionization tandem mass spectrometry method

•A sensitive LC-MS/MS method for analysis of triacylglycerol regioisomers was developed.•An optimization algorithm for quantitative analysis is included.•Hundreds of regioisomers of Finnish and Chinese human milk TAGs were analyzed.•Regioisomers of TAGs with standard deviation <17% covered 65mol% of the total TAGs.•The method is applicable for analysis of a wide range of fats and oils.