Innovative air-impingement jet drying of red cabbage: Kinetic description and prediction of the degradation of cyanidin-3-diglucoside-5-glucoside and cyanidin

Red cabbage (RC) is a vegetable rich in anthocyanins. This study analyzed comparative applications of RC hot air drying (HAD) at 60 °C, which took 810 min, and RC air-impingement jet drying (AIJD) at 60 °C, which took 630 min. The results indicated that AIJD retained a better color in the RC than HAD. Ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS) analysis of the RC showed that 28 anthocyanins and one anthocyanidin (cyanidin (C)) were derived from cyanidin-3-diglucoside-5-glucoside (C3dG5G). Multivariate analysis revealed that AIJD degraded the C3dG5G and C in the RC, which were revealed as 1.5-order and 2-order reactions, respectively. Moreover, the AIJD-induced degradation of C3dG5G and C were non-spontaneous and endothermic reactions. These kinetic equations could also be applied to predict the content of C3dG5G and C during degradation. Therefore, the results of this study could be beneficial in improving the AIJD of RC for more effective preservation.