Combining plant and dairy proteins to enhance the oxidative stability of microencapsulated lipids in spray-dried powders

This study investigates the oxidative stability of spray-dried emulsion powders using single plant (pea or soy), dairy (milk), or hybrid (plant-dairy) protein systems for encapsulation. Emulsions were produced and spray-dried and powders stored for 91 days under controlled conditions. Lipid oxidation was monitored through peroxide value, free radical concentration (Miniature Electron Spin Resonance Spectroscopy), and GC-MS analysis. Hybrid protein systems showed superior protection of encapsulated lipids, with 15-times lower accumulation of hydroperoxides and 2-3 times lower free radical concentrations compared to single-protein formulations. Furthermore, the formation of total volatiles of hybrid samples plateaued after 28 days, while it continuously increased for all single protein formulations, demonstrating that also secondary lipid oxidation was reduced in hybrid samples. The findings suggest that the combination of plant and dairy proteins synergistically improved the oxidative stability of encapsulated lipids, laying a promising groundwork for the development of clean-label, shelf-stable food powers.