Pure analytical standards for the major saponins present in processed soy products, the group B saponins (soyasaponins I, II, III and IV), were isolated in mg quantities by a combination of processing, precipitation/re-solubilisation, TLC and preparative HPLC. These standards were determined to be pure by LC-ESI/MS analysis and NMR. The standards were used to perfect a facile analytical HPLC method using spectrometric detection to determine the percent composition of the group B soyasaponins in various products from processing of soybean.