Evaluation of the impact of cassava fermentation time on the physico-chemical and biophysical characteristics of Agbélima

Abstract

Agbelima quality depends on both raw material characteristics and processing conditions, particularly fermentation time, which varies widely during market distribution and may cause heterogeneity in products offered to consumers. This study evaluates the effect of fermentation time on the physicochemical properties of Agbelima (pH and titratable acidity) and on the biophysical properties of dried Agbelima flour and cooked paste Agbeli (rheological and textural parameters), using consumer-derived ideal acceptability ranges as a reference. Cassava roots from the variety BEN 86052 were processed into Agbelima by two producers (P1 and P2) following a standardized local process. Fermentation was monitored for 168 h (7 days) with regular sampling. Results showed a rapid drop in pH at the early stage of fermentation followed by stabilization, while titratable acidity increased progressively, confirming the expected inverse relationship. Based on consumer-defined ideal ranges, a first screening identified a fermentation window of 72 to 120 h, which was further refined using biophysical measurements. Rheological analysis of dried Agbelima flour indicated that final viscosity generally remained within the ideal range, whereas peak viscosity was the most sensitive parameter to fermentation time, particularly for producer 2 where a significant decrease occurred after 72 h. Textural properties of cooked Agbeli paste varied only slightly between 72 and 120 h within each production; however, samples fermented for 96–120 h, especially from producer 2, were closer to consumer expectations (higher firmness and extrusion force, and adhesiveness more frequently within the ideal range). Principal component analysis combining rheology and texture (87.5% of total variance explained) confirmed that the 96–120 h samples achieved the best overall technological compromise. In conclusion, fermentation times between 96 and 120 h are the most suitable to obtain Agbelima with physicochemical and biophysical properties close to consumer expectations, with 96 h proposed as an operational recommendation to optimize product quality while limiting processing time.