Extraction of jojoba oil by pressing and leaching

Jojoba oil extraction by pressing alone, pressing followed by leaching, and leaching alone were investigated. The extraction process by first and seco nd pressing followed by leaching gave about 50% by weight oil with referenc e to total seed, which is in agreement with what has been reported previous ly. The extraction by leaching process was carried out using different solv ents. These solvents were; hexane, benzene, toluene, petroleum ether, chlor oform, and isopropanol. Hexane, benzene, and petroleum ether gave the highe st yield (all about 50% by weight oil with reference to total seed), but wh en cost is considered, petroleum ether is recommended as the best solvent t o leach jojoba oil. The yield obtained in this work for leaching by hexane and benzene are 3-5% and about 10% for isopropanol more than those reported in the literature. Traces of solvent remained with the extracted oil after simple distillation followed by a second stage distillation via a Rotavapo ur apparatus. These traces slightly affected some of the oil properties suc h as pour point and Bash point. (C) 2000 Elsevier Science S.A. All rights r eserved.