Aqueous extraction—An alternative oilseed milling process

Abstract

Oil can be removed from oilseed materials by a process which consists of an aqueous extraction of the comminuted seed, followed by a centrifugal separation which divides the aqueous extract into oil, solid, and aqueous phases. The protein may be recovered in the solids or aqueous phase, depending upon the conditions selected. Unit operations of this process are grinding, solid-liquid separation, centrifugation, demulsification, and drying of products. Aqueous extraction has been applied, to date, to coconuts and peanuts. For coconuts, a procedure has been developed to recover 93% of the oil and 91% of the protein. The major protein product is 25% protein and, when reconstituted in water, forms an acceptable beverage. The estimated production cost of this product is $.24/lb. For peanuts, the recovery of oil was 89% and protein 92% for the concentrate procedure, whereas the corresponding values for the isolate procedure were 86% and 89%, respectively. The costs of production were estimated as $.17/lb of concentrate (67% protein) and $.28/lb of isolate (89% protein). Aqueous extraction offers several advantages over conventional solvent extraction-less initial capital investments, safer operation, capability of discontinuous operation, and production of a variety of products. Another advantage of aqueous processing is the capability for utilization of certain chemicals to remove or inactivate undesirable sub-stanc_es. In the case of peanuts, hydrogen peroxide -and sodium tiypoehtorite have proven to-be effective for destruetioa of aflatoxins. Aqueous processing has the potential for application to a variety of other oilseeds.

Alternative Techniques for Defatting Soy: A Practical Review

“…The unit operations for aqueous extraction of oil and protein from soy have remained largely unchanged since they were initially described (Sugarman 1956;Cater et al 1974;Lusas et al 1982;Rosenthal et al 1996). The process involves various steps which are highlighted in Fig.…”

“…Initially, the technique was developed for processing high fat oilseeds such as peanuts. It was eventually suggested that the technique could be applied to soybeans (Cater et al 1974) which led to a focused effort to develop aqueous extraction techniques for the simultaneous extraction of oil and protein from soybeans. The bulk of this work was carried out at the Food Protein Research and Development Center at Texas A & M University in the late 1970s and early 1980s (Cater et al 1974;Lawhon et al 1981a;Lusas et al 1982).…”

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

“…AEP for oilseed extraction eliminates the potential of explosion and emissions of volatile organic solvents when using hexane. Simultaneous recovery of oil and protein by AEP is possible with lower equipment costs and energy consumption than hexane extraction [8][9][10]. AEP is based on the water soluble components of oilseeds dissolving in the water, thereby releasing the oil which was previously bound to the cell structure [11].…”

Pilot Scale Study of Vegetable Oil Extraction by Surfactant-Assisted Aqueous Extraction Process

“…AEP for oilseed extraction eliminate the potential for explosion and emissions of the volatile organic solvent hexane. Simultaneous recovery of oil and protein by AEP is possible with lower equipment costs and energy consumption than by hexane extraction (7,8). Because of the immiscibility of water and vegetable oil, AEP have consistently been report to produce vegetable oil superior in quality (lower phosphatide levels and peroxide values) to that produced by hexane-based processes (9,10).…”