Electrospun polycaprolactone nanofiber containing Ganoderma lucidum extract to improve chemical and microbial stability of rainbow trout fillets during storage at 4°C

The present study aimed to introduce a novel biocompatible food packaging system based on electrospun polycaprolactone (PCL) nanofiber containing Ganoderma lucidum extract (GLE) to improve the chemical and microbial stability of fresh rainbow trout fillets. For this purpose, PCL nanofibers containing 1–8% of GLE (w/w) were prepared and characterized. Also, their in vitro antibacterial and antioxidant properties were evaluated. Then, the effects of the PCL nanofibers without GLE and containing GLE 8% were investigated on the chemical and microbial qualities of fish fillets during 12-day storage at 4 °C. Results indicated that increasing GLE concentrations enhanced the in vitro antioxidant properties of PLC and the highest antioxidant activities belonged to PCL-GLE 8% (P ≤ 0.05). Moreover, trout fillets wrapped with PCL-GLE 8% nanofiber showed significantly better antioxidant results compared to the other experimental groups at the end of storage time (P ≤ 0.05). Neither in vitro nor fish model studies showed any significant antibacterial activity for PCL-GLE 8%. The following scores belonged to the control, PCL, and PCL-GLE 8% groups, respectively: pH (7.62, 7.42, and 6.93), peroxide value (8.33, 8.27, and 5.28 meq/kg lipid), thiobarbituric acid reactive substance (1.38, 1.34, and 1.06 mg MDA/kg of fish fillet), total carbonyl content (0.82, 0.60, and 0.50 nmol/mg protein), total viable counts (9.2 log10 CFU/g for all experimental groups), and total volatile basic nitrogen (36.54, 33.32 and 14.14 mg N/100 g sample). The findings of this study revealed that PCL-GLE 8% nanofiber can be employed as an active food packaging material for improving chemical stability of fresh rainbow trout fillets.