Preparation and evaluation of an active modified oxygen/ carbon dioxide preservative for packaged fresh-cut durian

In this study, a series of chitosan/copper nanocomposites (CS/Cu-NCs) served as catalyzers for VC to remove O 2 in food packages were successfully synthesized, characterized, and further utilized to prepare an active modified O 2 /CO 2 preservative. Transmission electron microscope, ultraviolet-visible, and infrared spectra confirmed CS/Cu-NCs #1–3 were successfully synthesized. Three components of the preservative were optimized, and the best formulation was: CS/Cu-NCs #2: VC: NaHCO 3 =0.5:1.5:0.15. It maintained relatively stable O 2 /CO 2 in the package at 10℃. Fresh-cut durian treated with 0 g (CK), 1.15 g (T1), 2.3 g (T2), and 3.45 g (T3) preservatives were stored at 10℃. Results showed that T1 group exhibited significantly ( P <0.05) higher firmness and VC content compared with CK at 12 d, indicating the best qualities. Key respiratory enzyme analyses verified that decreasing SDH, increasing G-6-PDH and 6-PGDH contributed mostly to the superior qualities of T1 group. This study could provide a prospective solution for packaged fresh-cut durian.