Breaking the biofilm barrier: harnessing PVA-Nisin technology to safeguard dairy products from persistent pathogens

This study explores the fabrication, characterization, and antimicrobial properties of polyvinyl alcohol (PVA)-based films incorporating nisin. Films prepared via casting display smooth, transparent surfaces, with Scanning Electron Microscopy (SEM) showing increased surface roughness upon nisin addition. Contact angle analysis confirmed enhanced hydrophilicity (p ≤ .05), while Fourier Transform Infrared Spectroscopy (FT-IR) revealed that the casting method preserved the chemical integrity of PVA and nisin. Mechanical testing demonstrated reduced Young’s Modulus, suggesting improved elasticity due to nisin’s plasticizing effect. Biofilm assays with Staphylococcus aureus and Listeria monocytogenes showed significant reductions in biofilm populations (p ≤ .05) within 24–48 hours. PVA-nisin films achieved up to 99.98% (3.8 log) and 99.84% (2.8 log) reductions for Staphylococcus aureus and Listeria monocytogenes, respectively. These findings highlight the potential of PVA-nisin films as antimicrobial materials, providing sustained nisin release to inhibit biofilm formation in dairy food processing environments.