Thermo-gelation of Ethyl-cellulose Oleogels
Oleogel formulations have been suggested as a promising platform for various food, pharmaceutical and biomedical applications. More specifically, ethyl-cellulose (EC) has been studied as a potential oleogelator due to its ability to directly structure liquid oil. EC is an exceptional polysaccharide demonstrating a unique array of properties allowing it to be used in various applications. The current manuscript reviews the EC structure and physiochemical properties in the native form as well as in oleogel formulations. EC is a linear semi-crystalline polymer that goes through glass transition at approximately 140 °C and melts at approximately 180 °C. Its physiochemical properties are strongly affected by its molecular weight. Gelation of oil using EC is achieved by increasing the mixture temperature above its glass transition followed by cooling to room temperature. This is a thermoreversible transition where the sol–gel and gel–sol transitions demonstrate hysteresis. These transition temperatures are strongly affected by polymer molecular weight, concentration, and solvent properties. The final gel properties can be altered and tuned using solvent type, thermal treatment, and addition of surface-active molecule. Thus, EC gel properties can be altered and tuned for a specific application using a variety of different approaches. Understanding the neat EC properties as well as the oleogel characteristics is essential in order to apply this unique polymer in a variety of applications.