SECONDARY STRUCTURAL RHEOLOGY OF A MODEL CREAM

The theology of a cream is determined by the structure formed by its i ngredients. The primary structural theology of O/W creams has been cha racterized by the gel network theory. Cetyl palmitate is frequently us ed to improve consistency, but its mechanism of action has not previou sly been determined. This study uses rheometry and thermal optical ana lysis to examine the structural theology of a model cream containing c etyl palmitate. Rheograms were obtained over the temperature range 25 degrees-40 degrees C. In general, the overall rheogram shape, indicati ve of the primary structure, changes little as a function of temperatu re. However, an inflection gradually disappears as the temperature inc reases. Photomicrographs of the melting sequence show the cetyl palmit ate embedded in the emulsifier network and illustrate the destruction of the cetyl palmitace secondary network structure. Photomonitor recor dings correlate the melting transition of the cetyl palmitate with the disappearance of the rheogram inflection.