A fermented novel food product from banana pseudostem waste: a promising pathway to enhance food security in sub-Saharan Africa

Rapid population growth in sub-Saharan Africa is increasing food demand, while opportunities for farmland expansion remain limited. Climate change is further constraining crop productivity, suggesting recycling waste within the framework of the circular economy. Banana pseudostem, a major plantation waste rich in nutrients, is underutilized as only inner-core used in food applications through drying, which reduce biomass recovery and sensory quality. This study therefore investigated lactic acid bacteria (LAB) fermentation as a bioconversion strategy for both inner and outer pseudostem wet biomasses, assessing physico-chemical dynamics and culturable microbial load. Moreover, the proximate composition of fermented inner and outersheaths and dried unfermented inner-sheaths was evaluated, and all data were analyzed using R software. The inner-sheaths showed a greater pH decline than the outer-sheaths, reaching 3.48 versus 4.34 by day 15, with slightly higher peak temperatures (29.80 vs. 29.05°C). Titratable acidity increased as pH decreased, while LAB counts peaked at 8.76 and 7.68 log CFU/g in the inner- and outer-sheaths, respectively, after 30 days. Meanwhile, aerobic counts declined sharply to 5.53–6.57 log CFU/g as LAB dominates.The high moisture content of sheaths supported early LAB proliferation but limited the growth of aerobic bacteria. Fermentation decreased carbohydrate and fat contents but increased protein, whereas ash and fiber in the inner-sheaths remained largely unchanged. Overall, both inner and outer-sheaths showed favorable proximate profiles, suggesting that at least 80% of the banana pseudostem biomass is suitable for food product development through fermentation.