Mechanistic kinetic model to elucidate lipid oxidation mechanisms in spray-dried microencapsulated oils

Lipid oxidation limits the shelf-life of dried microencapsulated oils (DMOs). Mathematical modelling approaches can deepen our understanding of the complex mechanisms and regulatory factors at play in such systems. In this study, we developed a mechanistic kinetic model to describe the oxidation of DMOs. The model parameters of reactions with specific emulsifiers (citric acid esters monoglycerides (CITREM), whey protein isolate (WPI), and pea protein isolate (PPI)) were used to assess their impact on oxidation. The model indicates that PPI has the most significant antioxidant effect through mechanisms such as undergoing self-oxidation and/or acting as a physical barrier. Additionally, compared to the full shelf-life testing, the model evaluates faster the antioxidant contribution of endogenous tocopherols and commercial antioxidant blends. Our modelling approach using "what-if" scenarios is a valuable digital tool to elucidate the mechanisms regulating lipid oxidation in DMOs with different emulsifiers and antioxidants.