The purpose of this study is to evaluate multienzyme hydrolysis as a pretreatment option to improve soybean oil solvent extraction and its eventual adaptation to conventional processes. Enzymatic action causes the degradation of the cell structures that contain oil. Improvements in terms of extraction, yield, and extraction rate are expected to be achieved. Soybean flakes and collets were used as materials and hexane was used as a solvent. Temperature, pH, and incubation time were optimized and diffusion coefficients were estimated for each solid. Extractions were carried out in a column, oil content was determined according to time, and a mathematical model was developed to describe the system. The optimum conditions obtained were pH？5.4, , and 9.7？h, and pH？5.8, , and 5.8？h of treatment for flakes and collets, respectively. Hydrolyzed solids exhibited a higher yield. Diffusion coefficients were estimated between 10？11 and 10？10. The highest diffusion coefficient was obtained for hydrolyzed collets. 0.73？g？oil/mL and 0.7？g？oil/mL were obtained at 240？s in a column for collets and flakes, respectively. Hydrolyzed solids exhibited a higher yield. The enzymatic incubation accelerates the extraction rate and allows for higher yield. The proposed model proved to be appropriate. 1. Introduction Seed oils represent 70% of global oil production, of which 30% is soybean oil. Oilseeds are the most important export items in Argentina [1]. In oilseeds, the vacuoles within cells contain oil, and both cell walls and vacuoles have to be broken in order to improve solvent extraction. Therefore, the preparation of the seed before solvent extraction is critical to maximize oil recovery. An alternative pretreatment to facilitate the release of oil from the seed could be enzymatic degradation. In this way, the partial hydrolysis of soybean seed cell structures with appropriate enzymes would increase permeability, which would in turn increase mass transfer [2]. An enzymatic treatment stage could be incorporated for industrial purposes without significant changes to conventional processes. The oil release obtained using this method could result in a higher extraction yield and/or smaller quantities of the organic solvents used [3]. In solvent extraction, pretreated oilseeds (porous solid matrix) come into contact with a pure solvent or a solvent mixture (miscella) to transfer the oil from the solid matrix to the liquid medium. While the principle of extraction is relatively simple, it is a complex mechanism [4]. In order to describe this process, the mass transfer phenomena
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