Thermal and storage degradation kinetics of corn anthocyanin-based natural red colorants in a model beverage system, and their gastrointestinal behavior

Purple corn pericarp anthocyanin-based freeze- and spray-dried natural red colorants encapsulated with maltodextrin (1%, w/v) and an uncoated sample were prepared. Surface morphologies and chemical structures were studied using scanning electron microscopy and FTIR analysis. Kinetic parameters for thermal degradation of anthocyanins at elevated temperatures were ascertained, and an excellent half-life t (1/2) value of 3.43 h at 121 °C was observed. Storage stabilities of anthocyanins in a model beverage system were evaluated at different temperatures, pH levels, and ascorbic acid concentrations over seven weeks. Relatively higher t (1/2) values were observed, implying excellent anthocyanin stabilities. Evaluation of color parameters during 1 h exposure at 121 °C demonstrated effective color retention. Anthocyanin concentrations decreased during the oral phase, increased during the gastric phase, and finally decreased in the intestinal phase of the simulation experiment. Superior thermal, storage, and color stabilities of purple corn anthocyanins demonstrate their excellent potential as natural food colorants.