EXTRACTION, OPTIMIZATION AND QUALITY CHARACTERIZATION OF OIL FROM HASS AVOCADO (PERSEA AMERICANA) VARIETY GROWN IN ETHIOPIA (WONDOGENET)

The purpose of this research was to extract, optimize and characterizethe qualityof oil from Hass avocado variety which is grown in Wondogenet, Ethiopia. Oil was extracted from Hass avocado pulp using soxhlet and ultrasonic extraction and some process parameter for optimization were carried out. Hass avocado is rich in fat (22.80±0.00%). The effects of three factors (particle size, solvent to sample ratio and extraction time) on the oil yield were considered. The optimum extraction conditions for soxhlet extraction were found to be at 8 h reaction time, particle size of 1.4mm and solvent to solid ratio of 20:1 with a maximum yield of 69.7%, while the optimum extraction conditions for ultrasonic extraction were found at 1.5 h reaction time, particle size of 2mm and solvent to solid ratio of 15:1 with a maximum percentage yield of 67.2%. The analyses of the oil characteristics demonstrated that the oil extracted by soxhlet extraction shows lower PV, FFA, MVM and Alkalinity than oil extracted using Ultrasonic extraction. The results of fatty acid profile displayed that the oleic and linoleic acid contents of the soxhlet extracted oil were higher than that of the Ultrasonic extracted oil while palmitic and butanoic acid were higher in ultrasound extracted oil. Generally, ultrasound assisted extraction showed a promising oil yield regarding short extraction time and low solvent consumption but its oil quality is lower than that of soxhlet extracted oil.