Aqueous Extended-Surfactant Based Method for Vegetable Oil Extraction: Proof of Concept

• Published in: Journal of the American Oil Chemists' Society Vol. 87; no. 10; pp. 1211 - 1220
• Main Authors: Do, Linh D, Sabatini, David A
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.10.2010; Springer-Verlag; Springer; Springer Nature B.V
• Subjects: Agriculture; Biological and medical sciences; Biomaterials; Biotechnology; Canola oil; Centrifugation; Chemistry; Chemistry and Materials Science; Efficiency; Emulsions; Environmental impact; Environmental protection; Enzymes; Extraction; Fat industries; Food engineering; Food industries; Food Science; Fundamental and applied biological sciences. Psychology; General aspects; Industrial Chemistry/Chemical Engineering; Microemulsions; Occupational exposure; Oils & fats; Oilseeds; Original Paper; Salinity; Seeds; Surfactants; Triglyceride analysis; Ultralow interfacial tension; Vegetable oils; Vegetables; Ultralow interfacial tension; Oilseeds; Extraction; Emulsions; Surfactants; Triglyceride analysis; Oilseed; Lipids; Vegetable oil; Method; Surfactant; Triglyceride; Oils and fats industry; Emulsion
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/s11746-010-1603-0

The use of hexane to extract vegetable oil from oilseeds is of growing concern due to hexane's environmental impact and because of worker exposure concerns. The goal of our work is to demonstrate that the aqueous extended-surfactant-based method is a viable alternative for vegetable oil extraction. In our method, ground oilseeds were dispersed in the aqueous surfactant solution, allowing the oil to be liberated from the seeds as a separate phase from the aqueous phase. The impact of pH, shaking intensity, shaking time and seed to liquid ratio on oil yield are presented. Extended-surfactants are a new type of surfactant with propoxylate (PO) and/or ethoxylate (EO) groups inserted between the hydrophilic head and the hydrophobic alkyl chain of the surfactant molecule. This unique structure of extended-surfactants enables them to produce ultralow interfacial tension with vegetable oils. We have found that at low aqueous concentrations (less than 0.3 wt%), extended-surfactant solutions are able to produce ultralow interfacial tension between aqueous extraction and vegetable oil phases. At optimum condition (seed to liquid ratio of 1-5, 30 min extraction at 150 shakes/min and 30 min centrifugation at 2,170×g) we achieved 93-95% extraction efficiency for peanut and canola oils at 25 °C. The oil quality produced from the aqueous extended-surfactant-based method was found to be comparable or even superior to that obtained from hexane-based extraction, further demonstrating the viability of aqueous extended-surfactant based extraction.