Physicochemical characteristics and fatty acids composition of crude oil extracted from blackberry (Rubus glaucus Benth) residues

Abstract

In this research the physicochemical characteristics and fatty acids composition of oil extracted from blackberry (Rubus glaucus Benth) residue were determined. Mature fruits from ‘‘La Colonia Tovar’’, Aragua state, Venezuela harvested on April 2001, were processed to obtain seeds and residues of pulp. This residue was extracted with n-hexane (Soxhlet method). The crude oil was assayed by means of COVENIN and AOCS methods. The results showed: Iodine index 160.16 cg I2/g, refraction index to 25ºC 1.4780 , saponification value 193.76 mg K0H/g, peroxide value 30.40 meq 02/kg, free fatty acidity 2.83% (oleic acid), insaponifiable value 2.77%, phosphorus content 0.22% and stability 3.09 h (AOM). The major fatty acids found were oleic acid (55.39%) and linoleic acid (29.51%).

Keywords

• blackberry
• oil
• proximate composition
• residues
• rubus glaucus