Modelling and Optimization of Oil Production from Breadfruits (Ukwa) Using Response Surface Methodology Approach

Abstract

This study investigated the optimisation of oil extraction from Treculia africana (breadfruit) seeds using response surface methodology (RSM). The effects of three process variables—extraction temperature (°C), extraction time (h), and seed mass dosage (g)—on oil yield were evaluated using Soxhlet extraction with ethanol. A central composite design (CCD) was employed to model and optimise the process, while analysis of variance (ANOVA) was used to determine the significance of each factor. The experimental maximum oil yield was 93.94%, obtained at 53°C, 2 h, and a seed mass dosage of 30 g. A quadratic model was fitted to the data (R² = 0.7630, adjusted R² = 0.5937); however, the predicted R² was negative (−0.4439), indicating limited predictive reliability and the need for cautious interpretation. Physicochemical analyses showed that the acid value, iodine value, and density were within the listed reference ranges, whereas moisture content, saponification value, ash content, calorific value, viscosity, and pH were outside their respective ranges. These findings indicate that Treculia africana seed oil may have potential as a resource for the food, cosmetics, and biofuel industries, while RSM provides a useful framework for examining its extraction process.