Experimental Comparison between Ethanol and Hexane as Solvents for Oil Extraction from Peanut Press Cake

Author(s)

Cristina Magalhaes, Paloma Jamily ; Goncalves, Daniel ; Aracava, Keila Kazue ; da Costa Rodrigues, Christianne Elisabete

• Document type: Journal article
• Source: FOODS; v. 12, n. 15, p. 17-pg., 2023-08-01.

Abstract

Ethanol (Et) has been suggested as a substitute for hexane (Hx) for use in the extraction of oils from different oleaginous matrices. In this study, Et and Hx were used to extract the residual oil present in a peanut press cake (PPC). Certain variables, such as temperature, solid/solvent ratio and the number of contact stages, in the sequential cross-current extraction process were evaluated; additionally, the effects of these variables on oils (POEt and POHx) and defatted solids (DSEt and DSHx) were explored. Hx exhibited an extraction yield of 86 & PLUSMN; 2% in two stages at 55 & DEG;C and a solid/solvent mass ratio of 1/4. Compared with Hx extraction, to achieve an Et extraction yield of 87 & PLUSMN; 4%, it was necessary to use a higher temperature (75 & DEG;C), a greater amount of solvent (solid/solvent ratio of 1/5) and a greater number of contact stages (3). POEt and POHx presented compositions in terms of fatty acids and triacylglycerols and physical properties similar to that of cold-pressed peanut oil (CPPO). POEt showed a more intense green/yellow hue and higher free acidity (1.47 & PLUSMN; 0.03%) than POHx and CPPO (0.82 & PLUSMN; 0.04 and 0.43 & PLUSMN; 0.02 free acidity mass %, respectively), indicating that the deacidification and bleaching steps in refining should be encumbered. DSEt and DSHx exhibited high protein contents (>45% by mass) and nitrogen solubilities (86 & PLUSMN; 6 and 98 & PLUSMN; 1%, respectively), indicating that they could be used to obtain proteins. (AU)

• FAPESP's process: 18/13207-6 - Extraction and computational simulation of ethanolic biodiesel production from peanut oil
• Grantee: Daniel Gonçalves
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/21252-0 - Equilibrium and production processes of biofuels and bioproducts
• Grantee: Antonio José de Almeida Meirelles
• Support Opportunities: Research Projects - Thematic Grants