Factors Affecting the Efficiency of Abrasive-Type Dehulling of Grain Legumes Investigated with a New Intermediate-Sized, Batch Dehuller

An intermediate-sized, batch dehuller capable of processing 2-8 kg of a wide variety of cereal or legume grains was developed. Grains are dehulled by abrasion provided by abrasive wheels (10 in, diam) mounted on a horizontal shaft. The dehuller was successfully applied to eight legume grains varying widely in seed characteristics. The yield of dehulled grain after at least 90% of the hull had been removed, ranged from 74-89%. Dehulling efficiency, a measure of the amount of hull in the abraded material, ranged from 0.11-0.72. Multiple-regression analysis showed that greater than 75% of the variability in dehulling efficiency or yield could be accounted for by seed hardness and resistance to splitting of the seed into individual cotyledons.