Abstract:In order to explore the demulsification mechanism of soybean oil emulsion produced by aqueous enzymatic method, the effects of jet cavitation pressure, jet cavitation temperature and jet cavitation time on the demulsification mechanism of soybean oil emulsion were investigated by light scattering particle size analysis, demulsification rate, total oil extraction rate and emulsion microstructure. The results showed that the demulsification rate and total oil extraction rate were increased with the increase of jet cavitation pressure (0.2~1.0MPa), jet cavitation temperature (80~120℃) and jet cavitation time (5~25s). After the complete demulsification, the demulsification rate and total oil extraction rate were decreased. The particle size distribution of emulsion and laser confocal microscopy showed that the dispersed small size oil droplets were changed into larger diameter oil droplets after demulsification. On the basis of single factor experiment, response surface methodology was used to optimize the process conditions of jet cavitation assisted hydrolysis demulsification. The optimum demulsification conditions were determined as follows: jet cavitation pressure was 0.8MPa, jet cavitation temperature was 100.92℃, jet cavitation time was 21.38s. Under this condition, the demulsification rate was 90.29%, and the total oil extraction rate was 87.06%. The research result provided a theoretical basis for jet cavitation assisted enzymatic demulsification technology, and it was beneficial to the industrial application and promotion of aqueous enzymatic oil extraction technology.