Evaluation of extraction methods on the physicochemical quality of noni oil (Morinda citrifolia) grown in Senegal

This study aimed to evaluate the effects of two extraction methods on the physicochemical quality of oil extracted from Morinda citrifolia seeds.The oil was extracted by maceration and Soxhlet methods using heptane as solvent.The analyses included moisture, refractive index, acid value, acidity, peroxide value, iodine value and saponification value.The seed recovery yield was 6.635 0.841 %.The oil extraction yields by maceration (cold extraction) and Soxhlet extraction were 8.179% and 8.238%, respectively.Evaluation of the physicochemical parameters revealed the following results: 0.318% moisture in the oil extracted by maceration compared to 0.075 % in that obtained by Soxhlet; a refractive index of 1.464 for both oils, 4.941 mg KOH/g for the maceration and 7.940 mg KOH/g for the Soxhlet oil; an acidity of 2.483% in the maceration oil and 3.991% in the Soxhlet oil; a peroxide index of 8.353 meqO2/kg for the maceration oil and 7.250 meqO2/kg for the Soxhlet oil; an iodine index of 74.871 g/100g for the maceration oil and 72.333 g/100g for the Soxhlet oil; finally, a saponification index of 145.509 mg KOH/g for the maceration oil and 191.124 mg KOH/g for the oil extracted by Soxhlet.These results indicate that extraction methods significantly influence on the quality of oil extracted from Morinda citrifolia seeds.