Effect of Roasting Conditions on the Sensory and Proximate Composition of Sesame Seeds in Kogi State

Sesame (Sesamum indicum) seed is an economically significant oilseed crop cultivated extensively in Kogi State, North Central Nigeria. Roasting is a critical value-addition step that influences the sensory, nutritional, and functional properties of the processed seed. This study investigates the effect of roasting temperature and time on the sensory profile and proximate composition of sesame seeds from Okene and Kabba production zones. Sesame seeds were roasted at 120, 150, and 180 degrees Celsius for durations of 5, 10, and 15 minutes in a full factorial design. Sensory evaluation of colour, aroma, taste, and overall acceptability was conducted by 30 trained assessors familiar with roasted sesame products. Proximate composition was determined following AOAC methods, and oil content was measured by Soxhlet extraction. Colour was objectively measured by Hunter Lab colorimeter. Results showed that roasting at 150 degrees Celsius for 10 minutes produced the highest sensory scores and a desirable golden-brown colour. Higher temperatures and longer durations resulted in significantly reduced oil content and darkened colour due to Maillard browning. Proximate composition changes were modest within optimal treatment parameters. The study draws on recent literature on thermal processing effects on oilseed quality and contributes to standardisation of sesame roasting for commercial processors. Findings are relevant to the sesame value chain and export quality improvement efforts in Kogi State. Keywords: sesame, roasting, sensory evaluation, proximate composition, Kogi State