Investigation of astringency of extracts obtained from selected tannins-rich legume seeds

Extracts prepared from legume seeds (faba bean, broad bean, pea, lentil, bean) were examined for their astringency and proteins precipitation activity. The sensory astringency of this material was evaluated using the method of sensory scaling and expressed as sensation of astringency indices (SAI). Proteins precipitation activity of extracts was estimated spectrophotometric methods. The HPLC analysis was performed for determined individual phenolic compounds in the extracts. The statistical analysis of the results indicated a statistically significant correlation between SAI and proteins (BSA and HSPs) precipitation capacity of samples. The HPLC analysis of the extracts demonstrated the presence of low-molecular phenolic substances such as flavonoids (quercetin, kaempferol) and phenolic acids (p-coumaric, ferulic sinapic).