Influence of high intensity sweeteners and sugar alcohols on a beverage microemulsion.

The present paper shows the effects of added sugars and sweeteners on the clearing temperature of a highly water dilutable fatty acid salt microemulsion used as a model of a beverage concentrate. There is a twofold interest in this work. The first one is practical and relates to the fact that many fatty acid salt surfactants can be used in food without major regulatory restrictions. As is shown here, they allow making highly stable microemulsions even at neutral and acidic pH. The second one is more of scientific interest. The model system can be used to study the effect of sugars and sweeteners on the formulation stability depending on their charges, amphiphilic properties, and localization in the microemulsion interfacial film. An important practical result is the discovery of the possibility to formulate highly dilutable microemulsions at neutral or slightly acid pH with a good taste in presence of sucralose. Further, a significant decrease of the pKA of the fatty acid is observed in presence of stevia, thus allowing transparent, fairly stable systems at neutral pH.