Kinetic modelling of anthocyanins and vitamin C degradation in a maqui-citrus beverage during storage for different sweeteners and pasteurization treatments

Kinetic models to describe the degradation of anthocyanins (first-order model) and vitamin C (system of ordinary differential equations) in a novel beverage, has been used as a tool to identify the most relevant variables for the degradation kinetics and to support shelf-life estimation. The models were based on an empirical dataset, accounting for the effect of a prior processing treatment (HHP at 400 MPa- 180s; HHP at 600 MPa-180s; thermal treatment at 85 °C for 15s), storage temperature (4 or 20 °C), and the use of two different sweeteners (sucralose or stevia). Using model selection (based on AIC), we conclude that the degradation kinetics depends on a complex combination of process and product parameters. A strong temperature dependence on anthocyanins and vitamin C was observed during pasteurization. Products treated by HHP resulted in higher vitamin C concentrations during storage than those thermally treated. Finally, an interaction with the sweetener resulted in a slight stabilization of bioactive compounds. In conclusion, this study demonstrates the complexity of the degradation process of bioactive compounds in these beverages, advocating that nonlinear kinetic models serve as a tool to identify the most relevant parameters, ultimately supporting product formulation and shelf life estimation.