Arabic gum-nitroso-hemoglobin as natural antimicrobial conjugates for enhanced preservability of minced beef subjected to freeze–thaw process: evidence from HS-SPME/GC–MS, LF-NMR, and docking analysis

We elucidated the effects of nitroso-hemoglobin-Arabic gum (N–H + GA) conjugates on the quality and safety of inoculated minced beef during cold-storage by investigating their microbiological and chemical changes, volatile compounds and amino acid profile. Results showed that N–H + GA significantly reduced the total bacterial counts, Salmonella, Pseudomonas, and Staphylococcus on day 7 of stored minced beef (p ≤ 0.05). Meanwhile, with the increasing storage time, water relation time and water populace ratios also fluctuated. N–H + GA significantly declined the decreasing ratio of T_21-values in refrigerated and freeze–thaw-refreeze minced beef compared to the inoculated beefs. Furthermore, N–H + GA (5 g/kg) maintained the levels of different amino acids, namely Glu, Cys, Asp, Thr, Ser, Ala, Ile, Leu, Tyr, Lys, His, and Arg. It also kept the volatile components than the control treatment after 3 weeks of frozen/refrozen storage. This is mostly due to the binding between hemoglobin-glycoprotein conjugates with myosin via H-bonds and electrostatic forces as supported by Lib-dock outcomes. Our results implied that using N–H + GA, as a natural colorant-based conjugate, could maintain the safety and quality of minced beef during freeze–thaw-refreeze.