Effect of enzyme pre-dehulling treatments on dehulling and cooking properties of legumes

Abstract

Xylanase and protease pre-treatments were used to evaluate the dehulling properties of green gram, black gram, red gram and horse gram. Xylanase-mediated degradation of non starch polysaccharides (NSP) has facilitated the easy dehulling of green gram, black gram and horse gram. Xylanase pre-treatment of horse gram resulted in 84.4% dehulled kernels, whereas, 78.4% and 75.7% dehulled kernels were produced in green gram and black gram, respectively. However, protease pre-treatment was more efficient in improving the dehulling properties of green gram and black gram in addition to red gram with higher amount of dehulled kernels (>78%) and lower amount of fines. Selective improvements in the degree of dehulling, dehulling index and dehulling efficiency were observed in enzyme treatments compared to buffer- and oil-treated controls. Enzyme pre-treatments did not alter the cooking properties of dehulled legumes. These results indicate that, partial degradation of NSP and/or proteins of mucilage, which is present in between hulls and cotyledon by enzymes has facilitated the improvement in the dehulling properties of legumes.