Abstract
The current study was conducted to fabricate poly(vinyl alcohol) (PVA) electrospun nanofiber mats containing anthocyanin-rich Althaea Officinalis extract (AOEX; 5, 10, 15 and 20%v/v) to monitor the spoilage and enhance the shelf-life quality of rainbow trout fillet. The AOEX displayed colour change when subjected to the different pH buffer solutions. The optimum conditions for fabricating PVA nanofibers with a minimum diameter (204.9 nm) were found using response surface methodology (RSM). The viscosity, electrical conductivity and surface tension of PVA-AOEX solutions were significantly changed up to 993.2 cp, 1275.65 µS/cm and 54.16 mN/m, respectively, by increasing AOEX content. The IC50 values for DPPH and ABTS radical scavenging by AOEX were 375 and 800 ppm, respectively. The phytochemical and antibacterial properties of PVA-AOEX were improved by adding AOEX content. Microscopic images confirmed the increase in the diameter and roughness of PVA-AOEX nanofibers by adding the AOEX up to 480.9 nm. After the addition of AOEX, the PVA-AOEX nanofibers become more hydrophilic (θ = 47.6–73.1°), but the melting temperature (Tm) values of the PVA-AOEX nanofiber mats have decreased (217.6°C). Fourier-transform infrared spectroscopy (FTIR) showed that adding AOEX and electrospinning process does not have a negative effect on the structure of the PVA. The PVA-AOEX nanofibers mats, revealing that the real-time multi-functional innovative packaging changed colour from white to brown and, at the same time, exceeded the total viable count (TVC) and total volatile basic nitrogen (TVB-N) acceptance limit of rainbow trout fillet.