Formulation and characterization of monodisperse O/W emulsions encapsulating astaxanthin extracts using microchannel emulsification: Insights of formulation and stability evaluation

[Display omitted] •Uniform sized O/W emulsions encapsulating astaxanthin were formulated.•Monodispersed droplets with d3,2 of 35–27μm was generated from MCE.•Appropriate operating conditions and astaxanthin concentration for MCE were found.•The collected O/W emulsions had better physical stability at 25°C.•Encapsulation efficiency of astaxanthin was >98% after 15days of storage at 25°C. The study used straight-through microchannel emulsification (MCE) to encapsulate different extracts of astaxanthin (AXT) in oil-in-water (O/W) emulsion droplets. We used silicon microchannel plates (WMS 11-1) containing 13,752 discrete 10×104μm microslots, connected to a circular microhole with a diameter of 10μm. Two different AXT extracts (AstaReal (AR) and Zenthin® (ZR)) based upon concentration and without purification was used as encapsulants in the dispersed phase, while different emulsifiers (1% (w/w) SDS, ML-750, MO-7S, Na-Cs and ML) with different stabilizing mechanisms were used as the continuous phase. The MCE was conducted at a dispersed phase flow rate of 1mLh−1. Successful emulsification was conducted with a Sauter mean diameter of 35–37μm and relative span factor