Optimum Boiling Duration and Its Effect on Nutritional Quality and Acceptability of Mechanically Dehulled Unfermented Locust Bean Seeds.

Most locust bean processing is still carried out locally in Africa. Dehulling is one of the major challenges encountered in traditional processing of locust bean seeds. Boiling time prior to dehulling is vital for nutritional status of locust bean. Hence, this study explored the influence of boiling duration before dehulling on the nutritional quality of mechanically dehulled locust bean seeds. The samples were subjected to four different boiling durations (1∼4 h) and the resulting effects on the overall acceptability, proximate composition, mineral content, and pH were evaluated. Locust beans boiled for 2 h and dehulled at the speed of 398 rpm gave the highest crude protein content, crude fiber, crude fat, and ash content. The pH ranged from 5.48 to 5.77, while boiling improved the mineral content ranging from 0.25∼0.48 mg/100 g (potassium), 16.80∼28.00 mg/100 g (calcium), 3.85∼6.73 mg/100 g (sodium), and 40.00∼52.40 mg/100 g (magnesium). The tedious labour during dehulling of locust bean seeds can be reduced at 398 rpm dehulling speed without adversely affecting the slightly acidic status and nutritional quality; thus enhancing quality and overall acceptability. Adoption of boiling raw locust bean seeds for 2 h under pressure prior to dehulling is a valuable procedure to eliminate long hours of boiling and tedious labour during local and industrial production.