Effect of different post-harvest treatments on antinutritional factors in seeds of the tribal pulse, Mucuna pruriens (L.) DC.

The effect of soaking, cooking and autoclaving on the levels of certain antinutritional factors present in the tribal pulse, Mucuna pruriens, were studied. The amount of reduction of total free phenolics was found to be greater in sodium bicarbonate solution (56%) compared to distilled water (47%); subjected to cooking and autoclaving these were further reduced to 49%. Autoclaving (45 min) significantly reduced the tannin content (71%). Insignificant reduction in content of L-DOPA was observed in all the processes. Distilled water soaking was found to be ineffective in eliminating lectin activity; whereas very significant reduction was noticed against all the human blood groups ABO without any specificity in samples subjected to cooking and autoclaving. Soaking in distilled water was more effective (27% reduction) than sodium bicarbonate solution (17% reduction) in lowering the contents of phytic acid. Cooking for 90 min and autoclaving for 45 min resulted in eliminating phytic acid to the extent of 18% and 44%, respectively. Loss of HCN was greater under autoclaving (75%) than the other processes studied. Of the three oligosaccharides analysed, soaking effected maximum reduction in the level of stachyose followed by verbascose and raffinose. Autoclaving effected greater reduction (59-81%) compared to ordinary cooking (40-60% reduction). Of all the different treatments studied, autoclaving seemed to be the best method in eliminating the investigated antinutrients more efficiently except L-DOPA.