Optimization of lipid nanoparticle formation for beverage applications: Influence of oil type, cosolvents, and cosurfactants on nanoemulsion properties

• Nanoemulsion clarity depends on oil type and cosolvent/cosurfactant addition.
• Nanoemulsion stability depends on oil type and cosolvent/cosurfactant addition.
• Clear stable nanoemulsions can be formed by controlling composition.

The influence of flavor oil composition, cosolvents (glycerol and propylene glycol), and cosurfactant (lysolecithin) on the formation and stability of lemon oil nanoemulsions stabilized by sucrose monoesters was examined. At ambient temperature, nanoemulsions containing 1-, 3-, and 5-fold lemon oils were stable to droplet growth, whereas those containing 10-fold lemon oil were unstable. For 10-fold lemon oil nanoemulsions, the droplet growth rate increased with increasing temperature, cosolvent addition, and decreasing lysolecithin concentration, which was attributed to the influence of these factors on the phase inversion temperature. Clear nanoemulsions could be formulated that maintained small mean particle diameters (d ≈ 81 nm) during storage at ambient temperature for 1 month. The information generated in this study is useful for designing stable flavor nanoemulsions for applications in functional foods and beverages.