Abstract

Cowpea is an essential leguminous crop that significantly contributes to the diet and economy of many regions. Actions have been undertaken to enhance the dehulling process to minimize loss, maximize efficiency, and improve product quality. This study focused on a black-eyed variety of cowpeas (Vigna unguiculata) to evaluate the effects of various operational conditions, including moisture content, dehulling time, and soaking time, on dehulling efficiency, percentages of un-dehulled and broken. Response Surface Methodology (RSM) was employed, utilizing a 3² factorial i-optimal randomized design and analysis of variance (ANOVA) at a 5% significance level, using Design Expert software. A sample weight of 4.08 kg was tested in triplicates, with moisture levels set at 8.3%, 10.32%, and 12.07% (wet basis). The samples were fed into the machine after different soaking durations of 5, 7.5, and 10 minutes for each replicate. The optimization process aimed to achieve optimum dehulling efficiency with reduced percentages of un dehulled and broken. The optimal conditions were predicted to be a moisture content of 12.07% (wet basis), a dehulling time of 7.6 minutes, and a soaking time of 9.9 minutes, resulting in a dehulling efficiency, percentages of un-dehulled and broken seeds of 87.3%, 5.9% and 6.8% respectively.