Quantification of Tannins in Four Species of Genus Mucna Seeds

Abstract

In order to make Mucuna seeds consumable, seeds are treated according to the following procedures: boiling, soaking followed by boiling in the presence of 0.5% KOH and finally soaking for a long time followed by boiling in the presence of 0.5% KOH, so that tannins can be removed. Preliminary studies done on the raw seeds of four Mucuna species revealed the presence of tannins. The results showed that the crushed seeds contained all high tannin with the content of 0.370 g GAE/100g DM, 0.336 g GAE/100g DM; 0.266 g GAE/100g DM and 0.203 g GAE/100g DM for Mucuna deerigiana, Mucuna nagaland, Mucuna cochinchinensis and Mucuna rajada respectively. The different methods of seed treatment significantly reduced the tannin content in Mucuna seeds. The method of soaking the seeds for 12 hours and then scalding in the presence of 0.5% KOH reduced tannins in Mucuna deerigiana, Mucuna nagaland, Mucuna cochinchinensis, and Mucuna rajada seeds by 47.29%; 48.21%; 66.16%; and 15.76% respectively. This method gave the highest tannin reduction rate.