Western Illinois University, Chemistry, Macomb, IL 61455
Syneresis in biopolymer structures is mainly controlled by thermodynamic factors. As result, bonds between hydrophobic sites start to form because water molecules in the micelles leave the structure from the dispersed phase. In this study, the effects of various biopolymers including guar gum, sodium alginate, cyclodextrin, Kappa-carrageenan, Iota-carrageen and Lambda-carrageenan were investigated to determine their ability to stabilize oil-in water emulsions against time-dependent syneresis. Duplicate emulsions, each containing one of the biopolymers, were prepared using power ultrasound and stored at 4ºC in 100 ml graduated cylinders. At time intervals of 24hr, the volume of each separated phase (water, oil, and solid) was recorded. The rate of syneresis in the emulsions was related to the amount of separated water. A ranking of the biopolymers made on the basis of their ability to retard syneresis was established and the rate of efficiency of biopolymers was found to be in Cyclodextrin > guar gum > Kappa-carrageenan > Iota-carrageenan > Lambda-carrageenan > sodium alginate. Further study is under way to explore relationships between the viscosity and turbidity of each polymer with its ability to stabilize emulsions. The results of this study are important for formulation and processing of food and drug systems susceptible to phase separation.