Fresh-cut fruits are highly perishable and susceptible to bacterial contamination; thus, effective preservation methods are necessary to extend their shelf-life and improve quality. Polysaccharides edible coating loaded with essential oil nanoemulsions have the potential to extend shelf life and improve quality. The effectiveness of this approach is dependent on the properties of the nanoemulsions, such as droplet size (DS) and stability. This study optimized the production of citral (CT) and citronella oil (CTO) nanoemulsions (CT-CTO-NEs) for use in fresh-cut apples, with a focus on the effect of DS on antibacterial efficacy. After testing different combinations of surfactants tween 80 (TW 80) and co-surfactants Propylene Glycol (PG), the results showed that the optimal CT-CTO-NEs had droplets size of less than 500 nm and were stable for 3 weeks at 4ºC. The highest antibacterial activity against Listeria monocytogenes and Escherichia coli was observed with the smallest DS (< 100 nm). This study highlights the importance of DS in the efficacy of essential oil nanoemulsions as an antibacterial coating for fresh-cut fruits. The smaller the droplet size, the better the antibacterial activity.