Essential oils (EOs) are aromatic oily liquids obtained from plant material (flowers, buds, seeds, leaves, twigs, bark, herbs, wood, fruits, and roots) (Burt, 2004). They are gaining a wide interest in food industry for their potential as decontaminating agents, as they are GRAS. EOs contain a range of natural compounds (e.g., thymol, linalool, and carvacrol), which have a broad AM spectrum against different pathogenic and spoilage microorganisms, including Gram-negative species such as E. coli, Yersinia enterocolit- ica, P.aeruginosa, and S.choleraesuis, Gram-positive bacteria such as L.monocytogenes, S.aureus, B.cereus, yeasts such as S.cerevisiae, Candida albicans, Debaryomyces hanse- nii, and molds such as Alternaria alternate, A. niger, Botrytis cinerae, A.flavus, and Penicllium roqueforti (Kuorwell et al., 2011).
Linalool, methyl cavicol, and carvacrol incorporated in LDPE have been evaluated by many researchers in antimicrobial packaging of cheddar cheese against E. coli, L.innocua, S.cerevisiae (Suppakul, 2004; Suppakul et al, 2006; Ruppika et al., 2006; Suppakul et al., 2008; Randniyom et al., 2008). All of the studies have shown the effects of these EOs to inhibit the microorganisms on surface of cheddar cheese.
Otero et al., (2014) showed the antimicrobial activity of oregano essential oil (OR) and Ethyl Lauroyl Arginate HCl (LAE) coated on polypropylene (PP) or polyethylene terephthalate (PET) against two E. coli O157:H7 strains using Zamorano cheese (a Spanish sheep's milk cheese). Allyl isothiocynate (AITC) is a mustard essential oil and could be employed in antimicrobial packaging applications (Nielsen and Rios, 2000; Suppakul et al., 2003a); it is reported as a compound that is able to inhibit mold growth in a range of products, including cheese. Dos Santos Pires et al. (2009) developed a sachet containing AITC and evaluated its antimicrobial efficacy against yeasts and molds, Staphylococcus sp., and psychrotrophic bacteria in sliced mozzarella cheese. The researchers concluded that antimicrobial sachet containing AITC has a potential use for sliced mozzarella, with molds and yeasts being the most sensitive to the antimicrobial effects.