This study investigates the effect of mixed fermentation on the microbial, nutritional, and sensory properties of a traditional African condiment, "Opey", which is made from locust beans and soybeans. Microbial profiling revealed a reduction in pathogenic organisms and an enrichment in beneficial lactic acid bacteria during the mixed fermentation. The proximate analysis revealed increased protein (42.1 g/100 g), fat (19.9 g/100 g), and mineral content (7.32 g/100 g) in Opey compared to individual fermentations. The pH dropped to 4.6 in mixed fermentation, indicating that lactic acid bacteria likely drove acidification. Sensory evaluation showed improved taste and texture scores. The results highlight the potential of soybean fortification to enhance the nutritional value and safety of traditional locust bean-based condiments
