Effects of chitosan coating combined with thermal treatment on physicochemical properties, bacterial diversity and volatile flavor of braised duck meat during refrigerated storage

Abstract

The current study aimed to assess the impact of chitosan coating (0.005 g/mL) combined with thermal treatment (85 °C for 30 min) on tenderness, lipid and protein oxidation, bacterial diversity, and volatile flavor compounds in braised duck leg meat under vacuum packaging during refrigerated storage (4 °C for 15 days). The findings revealed that the three preserved treatments significantly increased tenderness from days 1 to 3. There was a substantial decrease from days 6 to 12 compared to the control, but no significant differences were observed on day 15. Compared with the control, the three preserved treatments reduced TBARS values by 25.8%-78.6% (from days 6 to 12) and total sulfhydryl concentrations by 24.1%-75.7% (from days 3 to 9). The combination treatment had the lowest values (carbonyl concentration, TVC, and TEC) compared to the chitosan coating and thermal treatment, indicating a significant synergistic effect. The proportions of the four primary spoilage organisms, Brochothrix, Weissella, Acinetobacter, and Pseudomonas, were 74.8%, 76.3%, 70.7%, and 49.7% in control, chitosan coating, thermal treatment, and combination treatment, respectively. The combination treatment produced the most volatile flavor compounds (38 compounds) at the end of storage (15 days). Hexanal, 1-nonanal, 1-octen-3-ol, and 2, 3-octanedione were the main volatile flavor compounds, and the average relative peak area was above 80. Therefore, chitosan coating and thermal treatment could be developed as synergistic methods to preserve braised duck meat.