Rheological properties of a double emulsion nutraceutical system incorporating chia essential oil and ascorbic acid stabilized by carbohydrate polymer–protein blends

Four water-in-oil-in water (W1/O/W2) double emulsions were made by adding the primary emulsion (W1/O) containing 74% (w/w) of chia essential oil, 6% (w/w) of ascorbic acid, and a 0.2 dispersed phase mass fraction ( φ W 1 / O ) to aqueous solutions (W2) of mesquite gum (MG), maltodextrin DE-10 (MD) and whey protein concentrate (WPC) in different proportions (MG66–MD17–WPC17 and MG17–MD66–WPC17), and in a ratio of 1:2.12 and 1:4.12 W1/O to dry biopolymers blends solids. All the double emulsions showed type C morphologies and only slight changes in the volume-weighted mean diameter (d4,3) throughout the storage time, indicative of good stability, despite they presented bimodal size distributions, but the double emulsion formulated with a predominant proportion of MD and ratio 1:2.12 provided a higher stability against droplet coalescence. All the double emulsions displayed viscoelastic character dependent on frequency.