Annually, a huge amount of food additives is imported into the country for direct and indirect consumption in various food industries. Producing of these compounds needs high technology which often cause to increase the price of food products. On the other hand, awareness raising has led to use natural ingredients and additives. In this study, the efficacy and performance of the bio emulsifier which produced from probiotic bacteria Lactobacillus plantarum substrate PTCC 1896 was evaluated on the rice waste in the oil in water emulsion system. The Fourier Transform Infrared Spectroscopy spectrometer analysis confirmed the similarity of this extracted compound with other bioemulsifier. Furthermore, FTIR showed the carbohydrate and protein groups Which is a major component of this bioemulsifier . Critical Micelle Concentration of this compound was measured at 11 mg / ml. Oil-in-water was obtained by using this bioemulsifier polymer at a critical concentration point of this bioemulsifier. Results showed that, emulsification index of obtained bioemulsifier was much lower than those which were prepared with sodium dodecyl sulfate sodium synthesized emulsifiers. The produced emulsions have a 24-hour stability of more than 50% and a 48-hour stability of 39.75 to 45.05%. Moreover, the stability of the emulsions which prepared by centrifuge bioemolsifier was approximately the same as the chemical emulsifiers. The evaluation of surface tension exhibited that obtained bioemulsifier has the ability to reduce surface tension. Furthermore, this output is in the agreement with the surface tension reduction which was happened by the other lactobacillus. Based on the viscosity measurement, the viscosity of continuous phase was dependents on dilute emulsions. Moreover, viscosity was increased significantly by increasing concentratio of dispersed phase. Generally, the important factor Turbidity wa increased by increasing oil content. The rheological tests of emulsions exhibited Newtonian behavior in concentrations of less than 50% of the dispersed phase of emulsions while a shear-thinning liquid was observed in dispersed phase 50%. In fact, it can be concluded that the obtained emulsifier was able to make various emulsions with different type of rheological properties. Also, the measurement of the zeta potential of samples showed that this bioemulsifier polymer could produce relatively stable emulsions.Considering the advantages of using natural compounds, introduced bioemulsifier can be used in food emulsions. It is an alternative bioemulsifier chemical types which was produced by a probiotic bacteria based on cheap and waste culture . Key words : probiotic bacteria, emulsion, bioemulsifier
