COMPARATIVE PROPERTIES OF TANNIN-FREE AND TANNIN-CONTAINING CULTIVARS OF FABA BEANS (VICIA FABA)

Several common cultivars of faba beans (Vicia faba L.), grown under similar environmental conditions, had similar concentrations of condensed tannin. The average percent tannins in the testae of eight cultivars was 4.3 ± 0.2 SEM. Storage and growing conditions, however, appeared to have an influence on the concentration of condensed tannin. Assays of condensed tannins from a diverse group of cultivars resulted in the identification of three cultivars of Vicia faba that were tannin-free. These cultivars, all of which produce flowers, testae and hilums that are white in color, are also deficient in those compounds responsible for the formation of a dark-colored polymeric complex when exposed to oxygen. Tannin-free and tannin-containing faba bean cultivars also differed with regard to spectrophotometric properties and elution patterns following Sephadex LH-20 chromatography. The development of suitable cultivars of faba beans that are tannin-free and do not contain the compounds that are responsible for seed coat darkening would likely enhance their nutritional and organoleptic properties.