Poster Double emulsions stabilized by the mixture of xanthan-sodium caseinate Effect of pH and formulation process
Multiple emulsions are complex systems in which the droplets of the dispersed phase themselves contain small disperseddroplets . There are two types of multiple emulsions: water-in-oil-in water (W/O/W) and oil-in-water-in-oil (O/W/O).Due to their multi-compartment structure, these materials have many applications in the pharmaceutical, cosmetic and foodfields .These emulsions are thermodynamically unstable. However, they can be kinetically stable over a significant period,which determines their lives. This stability can be performed by molecules of synthetic surfactants. However, the use of thesesurfactants causes severe toxicity problems in humans and animals and can have an environmental impact. There is currentlya tendency toward replacing synthetic surfactants by natural molecules. Biopolymers such as proteins and polysaccharides aregood examples of natural surfactants commonly found in the food industry and can be used in the pharmaceutical industry .The objective of this study is to formulate multiple W/O/W emulsions by a mixture of natural biopolymers namely NC andXG using the direct process.The stability of double emulsions prepared was conducted for 20 days at various storage temperatures. The effect of pHformulation on the stability of emulsions prepared was studied. Measurements of the apparent viscosity of each formulationwere performed and compared with other work. In parallel with these measures, microscopic was performed about differentsystems formulated.The results obtained showed that the emulsions made by the SN / GX mixture kept good stability for one month. Thisstability is a function of pH of external phase. The optimal pH for the formulation of these double emulsions is 5 or 5.5.