Aplicação de vapor de óleo essencial de Mentha piperita L. no controle de Escherichia coli em vegetal

Abstract

The consumption of minimally processed vegetables requires attention to microbiological safety, as these foods are often consumed raw and may harbor pathogenic microorganisms or indicate inadequate hygiene and sanitation, such as Escherichia coli. In this context, essential oils have emerged as a promising natural alternative for microbial control in foods. This study aimed to evaluate the antimicrobial activity of peppermint (Mentha piperita L.) essential oil vapor against E. coli inoculated onto cabbage surfaces. The antimicrobial activity of several essential oils was first evaluated against foodborne bacterial strains using the agar disk diffusion assay. Peppermint essential oil, which exhibited the highest inhibitory potential, was subsequently selected for vapor-phase evaluation at different concentrations in vitro using a controlled-release system based on sachets containing sago pearls as the carrier material. Finally, its application was evaluated on cabbage leaves inoculated with E. coli. Peppermint essential oil exhibited the largest inhibition zones in the disk diffusion assay, particularly against E. coli and Listeria innocua. In the vapor phase, it demonstrated concentration-dependent antimicrobial activity, with the pure oil and the 50% dilution showing the greatest effectiveness. The sachet system containing sago pearls was effective at releasing volatile compounds and inhibiting bacterial growth. On cabbage surfaces, treatments with pure peppermint essential oil and its 50% dilution reduced E. coli. These findings indicate that peppermint essential oil vapor has potential as a natural and complementary strategy for the microbiological control of minimally processed vegetables.