Stability of anthocyanins and ascorbic acid in sonicated strawberry juice during storage

The stability of anthocyanins and ascorbic acid in sonicated strawberry juice during storage was investigated. Strawberry juice was sonicated at varying acoustic energy densities (AEDs) ranging from 0.33 to 0.81 W/mL and treatment times of 0-10 min. The degradation kinetics of sonicated samples followed first-order kinetics. Degradation rate constants were linearly correlated with AED (R ² > 0.91). Selected samples were stored for 10 days at 4 and 20 °C. A second-order polynomial model was employed to investigate the effects of storage time and processing variables. During storage higher loses were observed at a storage temperature of 20 °C compared to 4 °C. Predictive models developed for anthocyanins and ascorbic acid content were highly significant (P < 0.0001) and closely correlated to the experimental data (R ² > 0.91). Degradation mechanisms for anthocyanins and ascorbic acid due to sonication and storage are proposed.