Comparative Study of the Physicochemical Properties and Fatty Acid Composition of Some Indigenous Spices in Nigeria

Aim: This study evaluates the physicochemical properties and fatty acid composition of “Gbafilo” (Uapaca guineesis), “Omilo” (Parinari excelsa), “Country onion” (Afrostyax lepidphyllus), and “Taiko” (Zanthoxyllum zanthoxylloids).

Methods: The oil was extracted using n-hexane in a soxhlet apparatus and evaluated for their physical and chemical properties. Fatty acids profile was determined by Gas Chromatography (GC).

Results: The Refractive Index, Specific gravity and Oxidative stability values range between 1.44-1.46, 0.930-.0970, 40-72hr, respectively; While Iodine, Acid, Ester and Saponification values range between 94.14-105.20 I2/100g, 2.58-19.25mgKOH/g, 164.28-231.14mgKOH/g and 170.92-233.72mgKOH/g, respectively. Oleic acid was the predominant fatty acid in Omilo (92.98%) and Country onion (72.73%); While palmitic acid was predominant in Gbafilo (30.45%) and Taiko (28.09%). Linoleic acid was present only in Country onion (12.84%) and Omilo (2.04%).

Conclusion: These results suggest that the oil from these spices have potentials for use as food supplements and industrial raw materials in addition to their traditional use as condiments.