Antimicrobial activity of various essential oils and their application in active packaging of frozen vegetable products.

ABSTRACT

Essential oils (EOs) have potential utility as clean-label food preservatives due to their antimicrobial and antioxidant properties. In this study, various EOs were screened for their antimicrobial activities against Listeria grayi in vitro. The susceptibility of L. monocytogenes to select EOs was compared with that of L. grayi. The effectiveness of the selected EOs in inhibiting the growth of L. grayi on vegetable products was also investigated. The results showed that cinnamon and oregano EOs and carvacrol were effective in the vapor phase in inhibiting the growth of L. grayi as well as L. monocytogenes, with the susceptibility of L. monocytogenes to cinnamon EO being slightly higher than that of L. grayi. The packaging of green peppers with cellulose stickers impregnated with cinnamon EO at 556 µL/Lheadspace reduced the Listeria count to 1 log CFU/g after 2 days of storage as compared to 7.5 log CFU/g for controls.