In the present investigation, an HPLC-DAD/ESI-MS method for the complete analysis of tannins and other
phenolic compounds of different commercial chestnut bark samples was developed. A total of seven
compounds (vescalin, castalin, gallic acid, vescalagin, 1-O-galloyl castalagin, castalagin and ellagic acid)
were separated and quantified, being 1-O-galloyl castalagin tentatively identified and found for the first
time in chestnut bark samples. Thus, this method provided information regarding the composition and
quality of chestnut bark samples, which is required since these samples are commercialised due to their
biochemical properties as ingredients of food supplements