Effect of Soaking and Sprouting on Tannin, Phytate and In Vitro Iron in Underutilized Legumes - Horse Gram (Dolichos biflorus) and Moth Bean (Phaseolus aconitifolius)

The effect of simple processing techniques on tannin and phytate contents and in vitro iron availability in 2 underutilized legumes namely, horse gram (Dolichos biflorus) and moth bean (Phaseolus aconitifolius) was investigated. The processing techniques employed were soaking grains for 8 and 16 h and germinating the grains for 24 and 28 h. Results of the study revealed that horse gram had higher amounts of phytates and tannins. Soaking both the legumes for 8 and 16 h reduced the levels of tannins and phytates. Degradation of phytates and tannins was more pronounced after germination. In vitro iron availability increased after each stage of processing and was higher (33.9%) in moth bean as compared to horse gram (30.3%). It is concluded that soaking and germination are effective in significantly reducing antinutritional factors and concomitantly increasing iron bioavailability of legumes.