Extraction and Characterization of Oil from Sorrel (Yakuwa Seed) Hibiscus sabdariffa

Abstract

Hibiscus sabdariffa (yakwua seed) is one of economic value in tropical and subtropical regions around the world due to diverse industrial, medical and food uses. In this work, oil was extracted from the seed of Hibiscus sabdariffa using normal hexane as extracting solvent. The extraction was carried out at temperature of 70°C at 3-4 hours to ensure optimum oil yield. At a range of 3-4 hours extraction time and at a temperature of 70°C, the average oil yield obtained was 17.8%. The physical state of oil extracted is liquid/yellow greenish in colour with characteristic pleasant smell, relative density of (0.92 g/m3) , refractive index of (1.46),specific gravity of (0.91), and viscosity of (43.67mm2/sec) and the chemical parameters were also determine, the saponification value of (166.20 mgKOH/kg), acid value of (1.40 mgKOH/g), free fatty acid is (0.55 mgKOH/g), peroxide value of (6.90 mg/kg), iodine value of (80.03 g I2/100 g), and ester value of (164.79 mgKOH/g),are comparable with other oils extracted from other sources suitable for consumption. This reveals that the oil extracted from Hibiscus sabdariffa can be used both domestically and industrially, as the seed is already used by michika community for production of traditional maggi called dadawa in Hausa.