Changes in Some Antinutritional Components and In Vitro Multienzymes Protein Digestibility during Hydrothermal Processing of Cassia hirsutta

The seed of Cassia hirsutta was subjected to aqueous soaking and four hydrothermal processing techniques (atmospheric boiling, atmospheric steaming, pressure boiling, and pressure steaming). Soaking of the seed to varying hydration levels before hydrothermal treatments induced the reduction in the concentration of the antinutritional components. The lowest concentration of each of the antinutritional components was observed at 100% hydration level. The effects of hydrothermal techniques on the antinutritional components and protein digestibility were investigated. All the hydrothermal techniques caused significant reduction (P<0.05) in the antinutritional components. Boiling at elevated pressure resulted in greater reduction of antinutrients. The hydrothermal techniques caused total elimination of trypsin inhibitor activity. Reduction in the concentration of the antinutritional components after hydrothermal processing led to the increase in in vitro protein digestibility. The highest in vitro protein digestibility of 86.82% was observed after the legume seed was boiled at elevated pressure. Adoption of this underutilised legume will strengthen dietary diversity, improve feeding patterns, and prevent protein energy malnutrition especially in developing countries since the seed is a good source of nutritionally important nutrients.