Impact of emulsifier mixing and inhibitor type on Ostwald ripening of model food emulsions

This study examined how the ability to inhibit Ostwald ripening varies with ripening inhibitor type and how interfacial composition affects inhibitor efficiency. Emulsions were stabilized using Brij S100 and S20, which differ in ethylene oxide unit numbers, while medium-chain triglyceride (MCT) and ester gum (EG), possessing distinct molecular structures, were incorporated as ripening inhibitors. Ostwald ripening rate decreased with a higher proportion of Brij S20 at the interfacial membrane. Emulsions with increased Brij S20 content exhibited larger initial droplet sizes but lower polydispersity indices. Both inhibitors inhibited Ostwald ripening, but MCT was more effective than EG at the same weight percentage. Additionally, as the concentration of ripening inhibitors increased, droplet size decreased while polydispersity index increased. These findings suggest that interfacial composition and inhibitor type play key roles in emulsion stability, emphasizing the importance of molecular properties when selecting emulsifiers and inhibitors for effective Ostwald ripening inhibition.