Application of Advanced Emulsion Technology in the Food Industry: A Review and Critical Evaluation

The food industry is one of the major users of emulsion technology, as many food products exist in an emulsified form, including many dressings, sauces, spreads, dips, creams, and beverages. Recently, there has been an interest in improving the healthiness, sustainability, and safety of foods in an attempt to address some of the negative effects associated with the modern food supply, such as rising chronic diseases, environmental damage, and food safety concerns. Advanced emulsion technologies can be used to address many of these concerns. In this review article, recent studies on the development and utilization of these advanced technologies are critically assessed, including nanoemulsions, high internal phase emulsions (HIPEs), Pickering emulsions, multilayer emulsions, solid lipid nanoparticles (SLNs), multiple emulsions, and emulgels. A brief description of each type of emulsion is given, then their formation and properties are described, and finally their potential applications in the food industry are presented. Special emphasis is given to the utilization of these advanced technologies for the delivery of bioactive compounds.

Effect of Interfacial Ionic Layers on the Food-Grade O/W Emulsion Physical Stability and Astaxanthin Retention during Spray-Drying

The utilization of astaxanthin in food processing is considered to be narrow because of its substandard solubility in aqueous matrices and the instability of chemical compounds during the processing of food and the instability of chemical compounds during the processing of food. The investigation sought to evaluate multilayer emulsions stabilized by ionic interfacial layers of lupin protein isolate (LPI), ι-carrageenan (CA), and chitosan (CHI) on the physical stability of the emulsion as well as the retention of astaxanthin during the spray drying process. Primary emulsion (Pr-E) was prepared by adding LPI on oil droplet surfaces containing astaxanthin. The homogenization pressure and cycles to obtain the Pr-E were investigated. The secondary emulsion (Se-E) and tertiary emulsion (Te-E) were elaborated by mixing CA/Pr-E and CHI/Se-E, respectively. Emulsion stability was assessed under different environmental stresses (pH and NaCl). Astaxanthin retention of emulsions was determined immediately after finishing the spray-drying process. The results showed that Pr-E was stabilized with 1.0% (w/v) of LPI at 50 MPa and three cycles. Se-E and Te-E were obtained with CA/Pr-E and Se-E/CHI of 70/30 and 50/50% (w/w), respectively. The Se-E was the most stable compared to the Pr-E and Te-E when subjected to different pHs; nevertheless, once the NaCl concentration rose, no variations in the ζ-potential of all emulsions studied or destabilization were observed. The Se-E and Te-E derived provided higher astaxanthin retention (>95%) during the spray-drying process compared to Pr-E (around 88%). The results indicated that these astaxanthin multilayer emulsions show considerable potential as a functional ingredient in food products.