Lavandula angustifolia Essential Oil: GC–MS Composition, In Vitro Antimicrobial Activity, Vapor-Phase Efficacy on Fruit and Vegetable Models, and Anti-Escherichia coli Effect in Sous-Vide Potatoes

This study evaluated the antimicrobial activity of Lavandula angustifolia essential oil (LAEO) in vitro and in the vapor phase (in situ) against selected bacteria and yeasts, and against Escherichia coli in a sous-vide potato model, while characterizing its chemical composition. GC–MS identified 40 compounds covering 99.8% of the oil, dominated by linalyl acetate (37.4%) and linalool (34.3%). By disk diffusion and minimum inhibitory concentration assays on six bacterial and five yeast strains, the best inhibition zone was observed for Bacillus subtilis (17.33 mm) and the lowest for Candida parapsilosis (6.67 mm); the most favorable MIC was for Candida glabrata (MIC50 0.533 mg/mL). In situ, the highest dose (500 μg/L) yielded the strongest effects on fruit models: B. subtilis inhibition 96.55% (strawberry) and Listeria monocytogenes 86.13% (banana). On vegetable models, the lowest dose (62.5 μg/L) was most effective, with 95.93% inhibition of E. coli on potato and 96.55% of Yersinia enterocolitica on radish. Kinetic growth experiments confirmed the potential of LAEO, particularly at elevated temperatures, to suppress E. coli. In the sous vide potato food model, counts were monitored on days 1 and 7; groups treated with LAEO showed the most pronounced inhibitory effects. Across the sous-vide potato model, MALDI-TOF profiling most frequently recovered members of Enterobacteriaceae and Pectobacteriaceae, with E. coli, Pectobacterium carotovora subsp. carotovora, and Bacillus licheniformis among the dominant taxa. Overall, the data support the antimicrobial potential of LAEO, with a matrix- and dose-dependent action in the vapor phase and a modest but measurable benefit in sous-vide potatoes, indicating promise as a natural preservative for plant-based foods and SV potatoes.