Characterization of phenethyl isothiocyanate nanoemulsion loaded pectin/chitosan composite film and application in beef preservation

In this study, phenethyl isothiocyanate nanoemulsion (PNE) was formulated for creating composite films with pectin and chitosan. Two types of PNE/pectin/chitosan (PNE-PC) films (PNE-PC1, PNE-PC2) were made by introducing PNE into films with different pectin/chitosan (PC) contents. Compared to PC films, PNE-PC films showed greater hydrophilicity and improved elongation at break, with Fourier transform infrared spectroscopy, X-ray and microstructural observations confirming PNE's good compatibility within the film matrices. The PNE-PC2 film exhibiting a cumulative release of 55.3 % of PNE over 72 h and confirmed to inhibit Staphylococcus aureus for up to 48 h. Furthermore, beef covered with PNE-PC2 film showed lower total viable count compared to uncovered and polyethylene-covered groups. The film also stabilized beef pH and maintained total volatile basic nitrogen values within a safe range. It effectively suppressed sulfide production, preventing undesirable odors and extending beef shelf life, demonstrating the potential of PNE-PC films for food packaging applications.