Characterizing and alleviating the browning of Choerospondias axillaris fruit cake during drying

Abstract Non-enzymatic browning (NEB) is the major quality deterioration of Choerospondias axillaris fruit cake (CAFC) occurred during drying. The evolution of NEB, 5-Hydroxymethyl furfural (5-HMF), total phenols and ascorbic acid contents of CAFCs during hot air drying at various temperatures (50, 60, 70, 80 and 90 °C) were studied, and the anti-browning agents for inhibiting NEB were evaluated. The results showed that the browning index and 5-HMF content separately increased from 26.40 to 39.33 and 25.29–208.87 mg/kg; while the reductions of ascorbic acid and total phenols contents increased from 15.12 to 64.02 mg/100g and 10.54–35.40 mg GAE/100 g as the drying temperature increased from 50 to 90 °C. Drying at the programmed temperature (80-60-50 °C) could effectively decrease the browning of CAFC. Pearson correlation and Path-coefficient analysis further indicated that Maillard reaction was mainly responsible for the NEB of CAFCs. Adding 0.03%–0.05% sodium bisulfite showed the best effect on the NEB of CAFC, followed by 0.12% ferulic acid and 0.08% phytic acid. The ferulic acid and phytic acid could be used as a substitute of sodium bisulfite to improve the color of CAFCs.