Preparation of Food Flavor Nanoemulsions by High- and Low-Energy Emulsification Approaches

Abstract

Flavor ingredients are major contributors to the profile of food products. As these components are mostly volatile and hydrophobic, achieving their enhanced bioaccessibility and controlled release during processing is of utmost concern to food manufacturers. Emulsions prepared at nanoscale (2–200 nm) not only give the opportunity to protect the flavor ingredients but also enable achieving higher homogeneity in the emulsion system through produced smaller droplet size. Among developed approaches of high and low energy for preparation of flavor nanoemulsions, low-energy approaches give the possibility to develop nanoemulsions in absence of high shear and pressure, and are suitable selections for preparation of nanoemulsions for thermal-sensitive flavor components with the requirement of consuming less energy in comparison to high-energy methods. However, limitation of using synthetic surfactants might limit their applications for food systems and high amount of surfactant might be necessary to produce stable nanoemulsions with small droplet sizes. Preparation of nanoemulsions for encapsulation of food flavors applying low-energy methods is considered as a new emerging approach with potential for further research for development of ingredients applicable in food formulations and production of stable nanoemulsions at large scale. Considering the growing demand for food flavors, this review aims to highlight recent advancements in the application of high- and low-energy approaches for preparation of flavor nanoemulsions with the focus on discussing the main factors influencing stability and particle size of prepared nanoemulsions during development and storage and can provide insights on further production of nanoemulsions at an industrial large scale.