In the era of globalization, many classic industries in the quest for innovation have increasing turned to biotechnology, which has enabled diverse research opportunities without exerting a negative effect on productivity. Considering the growing interest in alternative products that minimize environmental impacts natural additives produced by microorganisms, known as bioemulsifiers (surfactants with excellent emulsifying properties) have attracted the attention of researchers. Thus, the objective of the present study was to evaluate the production of biosurfactant by Candida guilliermondii (UCP0992) grown in low-cost medium containing 5% molasses, 5% corn steep liquor and 5% residual frying oil, for 120 hours at 200rpm. Tests were carried out to evaluate the properties of the biosurfactant and then were analysed seven formulations of mayonnaise, evaluating the stability with the addition of guar gum and the biosurfactant isolated in the formulation of mayonnaise. After 30 days of refrigeration, the samples were evaluated for phase separation and the growth of pathogens. According to the results obtained, it was observed that the biosurfactant obtained by C. guilliermondii, had the capacity to reduce the surface tension of water from 71 mN/m to 28 mN/m and a yield of 21 g/L with a Critical Micellar Concentration of 0.7 g/L. All the mayonnaise analysed using the biosurfactant remained stable, with no pathogenic microorganisms. With that, it can be concluded that the biosurfactant has potential for application in the food industry.