Deconvolution of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry isotope patterns to determine ratios of A-type to B-type interflavan bonds in cranberry proanthocyanidins

► MALDI-TOF MS isotope patterns of cranberry proanthocyanidins were deconvoluted. ► Isotope patterns are repeatable and used to determine ratios of A- to B-type bonds. ► Method is precise and accurate for binary mixtures of procyanidins A2 and B2. ► Proanthocyanidins had at least one A-type bond in more than 91% of the oligomers. ► May be applied in authentication, standardization and efficacy of cranberry products.