The antimicrobial efficiency of edible films may be evaluated by different methodologies, including the overlay test/direct contact with the growth medium (laboratory media or real foods) and the vapor phase method, the latter being suitable to volatile compounds as well as applications in which there is little or no contact between food and packaging (Du and others 2009a). Apple puree edible films have been incorporated with different concentrations(0.5% to 3.0% wt.) of cinnamon, allspice, and clove bud essential oils, and had their antimicrobial activities against E. coli O157:H7, S. enterica, and L. monocytogenes evaluated by both overlay and vapor phase tests (Du and others 2009a). Regardless of the test method, none of the essential oils was able to inhibit microbial growth at 0.5%, whereas all of them did so at 3.0%. As for the intermediate concentrations, remarkable differences were observed between the 2 methods, indicating that the vapor phases of such essential oils lead to greater inhibitory effects. Similar dose- and phase-dependent outcome has been obtained for tomato puree films incorporated with 0.5 to 3.0% (wt.) of oregano, allspice, and garlic essential oils (Du and others 2009b).