Research background. The presence of Yersinia enterocolitica on raw food products raises the concern of yersiniosis as most of the berries are consumed raw. This is a challenging issue from the food safety aspect since it could in-crease the occurrence of foodborne diseases among humans. Thus, it is crucial to implement an effective sanitation before the packaging. Experimental approach. This study aims to synthesize and characterize thy-mol-loaded polyvinyl alcohol (Thy/PVA) nanoparticles as a sanitizer for post-harvest treatment of blueberries. Thy/PVA nanoparticles were characterized by spectroscopic and microscopic approaches, prior to the analyses of antimi-crobial properties. Results and conclusions. The diameter size of the nanoparticles was on av-erage 84.7 nm, with a surface charge of �11.73 mV. Based on Fourier transform infrared (FTIR) measurement, the Thy/PVA nanoparticles notably shifted to the frequency of 3275.70, 2869.66, 1651.02 and 1090.52 cm�1. A rapid burst was ob-served in the first hour of release study, and 74.9 thymol was released from the PVA nanoparticles. The largest inhibition zone was displayed by methicillin-resistant Staphylococcus aureus (MRSA), followed by Y. enterocolitica and Salmonella typhi. However, amongst these bacteria, the inhibition and killing of Y. enterocolitica required a lower concentration of Thy/PVA nanoparticles. The treatment successfully reduced the bacterial load of Y. enterocolitica on blueberries by 100 . Novelty and scientific contribution. Thymol is a plant-based chemical with-out reported adverse effects to humans. In this study, by using the nanotech-nology method of encapsulation with PVA, we improved the stability and phys-icochemical properties of thymol. This nanoparticle-based sanitizer could potentially promote the postharvest microbiological safety of raw berries, which may become an alternative practice of food safety. © 2023, University of Zagreb. All rights reserved.