A new active paper package based on the incorporation of cinnamon essential oil to solid wax paraffin as an active coating is proposed, developed, and evaluated. The antifungal activity of the active paper is tested against Rhizopusstolonifer, and the results demonstrate that 6% (w/w) of the essential oil in the active coating formulation completely inhibits the growth of R. stolonifer, whereas 4% still has strong antimicrobial activity in in vitro conditions. Then, active paper is evaluated with actual food, sliced bread, using different storage times. After 3 days of storage, almost complete inhibition is obtained with 6% cinnamon essential oil. Qualitative analysis by solid-phase microextraction and determination of cinnamaldehyde in the sliced bread were also performed and confirmed the strong correspondence between the inhibition of the mold and the amount of cinnamaldehyde in the bread.