Influence of β-carotene concentration on the physicochemical properties, degradation and antioxidant activity of nanoemulsions stabilized by whey protein hydrolyzate-pectin soluble complexes

The development of carrier systems for antioxidants is a current topic of study, providing protection against deleterious environmental factors and facilitate their efficient incorporation into more complex food systems. Nanoemulsions (NE) made up with natural ingredients may be considered as potential systems where bioactive compounds could be encapsulated. Whey protein hydrolyzate and high methoxyl pectin soluble complex (WPH-HMP) was obtained and used for stabilizing oil-in-water NE loaded with different beta-carotene concentrations (25, 50 and 75 mg.100 g(-1) emulsion). beta-carotene concentration affected the droplet size, stability, encapsulation efficiency, rheological properties, and protective capacity of the NE. Lower beta-carotene concentrations tended to yield NE with smaller average oil droplets sizes, higher encapsulation efficiency, apparent viscosity and viscoelastic moduli, and higher stability against droplet coalescence, creaming velocity and antioxidant activity degradation.