In this research a new antioxidant active food packaging has been developed and evaluated. It consists of an innovative system in which several natural antioxidants from rosemary (Rosmarinus officinalis L.) have been immobilized in a polypropylene film. The influence of concentration of the active compounds in the polymer and the contact system between the active film and simple food simulants have been studied. L-ascorbic acid, iron (II) and fatty acids from flax seed oil have been used as model compounds, being representative of the behaviour of different foodstuffs with respect to oxidation. Whereas ascorbic acid has proven to be not adequate for antioxidant quantitation purposes due to its prooxidant properties, increased protection of up to 30.1% for iron (II) and 62.0% for fatty acids were found. Among the advantages of this developed system, which extends the shelf life of packaged food, the non contact plastic-food requirements can be emphasized. (C) 2007 Elsevier Ltd. All rights reserved.