pubs.acs.org/JAFC Published on Web 08/27/2009 © 2009 American Chemical Society 8564 J. Agric. Food Chem. 2009, 57, 8564–8571 DOI:10.1021/jf901459e Effect of Mixed Antimicrobial Agents and Flavors in Active Packaging Films LAURA GUTIE ´ RREZ, † ANA ESCUDERO, ‡ RAMO ´ N BATLLE, †,§ AND CRISTINA NERI ´ N* ,† † Arago´ n Institute of Engineering Research (I3A), CPS, University of Zaragoza, Marı´a de Luna 3, 50018 Zaragoza, Spain, § Department of IþDþi, ARTIBAL S.A., Can˜ ada Real 12, 22600 Sabin˜  anigo, Huesca, Spain, and ‡ Laboratorio del An alisis del Aroma y Enologı´a (LAAE), I3A, Faculty of Sciences, University of Zaragoza, Spain. Active packaging is an emerging food technology to improve the quality and safety of food products. Many works have been developed to study the antimicrobial activity of essential oils. Essential oils have been traditionally used as flavorings in food, so they have an important odor impact but they have as well antimicrobial properties that could be used to protect the food. Recent developments in antimicrobial active packaging showed the efficiency of essential oils versus bread and bakery products among other applications. However, one of the main problems to face is the odor and taste they could provide to the packaged food. Using some aromas to mask the odor could be a good approach. That is why the main objective of this paper is to develop an antimicrobial packaging material based on the combination of the most active compounds of essential oils (hydrocinnamaldehyde, oregano essential oil, cinnamaldehyde, thymol, and carvacrol) together with some aromas commonly used in the food industry. A study of the concentration required to get the antimicrobial properties, the organoleptic compatibility with typical aroma present in many food systems (vanilla, banana, and strawberry), and the right combination of both systems has been carried out. Antimicrobial tests of both the mentioned aromas, the main components of some essential oils, and the combination of both groups were carried out against bacteria (Enterococcus faecalis, Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Salmonella choleraesuis, Yersinia enterocolitica, Escherichia coli), yeasts (Candida albicans, Debaryomyces hansenii, Zygosaccharomyces rouxii), and molds (Botrytis cinerae, Aspergillus flavus, Penicillium roqueforti, Eurotium repens, Penicillium islandicum, Penicillium commune, Penicillium nalgiovensis). The sensory properties of the combinations were evaluated with a triangular test and classification was by an order test; the odor threshold of the aroma compounds was also studied. The results reveal that none of the aromas had antimicrobial properties. The most antimicrobial compounds are thymol, carvacrol, and cinnamaldehyde, but none of them could be combined with banana aroma, whereas only thymol with strawberry aroma gave the right combined organoleptic profile. All of the antimicrobials under study could be combined with vanilla aroma, providing both antimicrobial property and the odor expected. KEYWORDS: Aroma; antimicrobial; active packaging; compatibility; sensory analysis; food protection INTRODUCTION The new lifestyle in which food products are in the supermarket for long periods demands progressive increase in their shelf life. However, a longer shelf life should not imply the loss of properties, especially concerning foodstuffs in which two vital topics, food safety and food quality, can be emphasized. Microbial infections including the presence of molds in many food products are the most limiting reason why many products cannot sit for long periods. Also, the decrease of quality in terms of organoleptic properties such as aroma losses ( 1 ) affects the length of the shelf life. For these reasons, the development of new systems to guarantee both the safety and quality of packaged food is more and more important. Several techniques are currently applied to fight food dete- rioration such as modified atmosphere, vacuum packaging, sterilization processes, and freezing. However, emerging techno- logies such as active packaging provide a promising solution in which the shelf life of the packaged product can be considerably extended without affecting either the food or the process, as the solution is in the packaging material itself. This way, the food can be healthier, more natural, and free of preservatives while main- taining all of the good properties, including food safety, as the preservatives remain in the packaging, which is not eaten. One of the key points in active packaging is the active agent to be used, and this depends on the objective of the new packaging material, which means if antimicrobial or antioxidant properties are required or even the specific aromas for a kind of food. This paper deals with a study carried out with active packaging that *Author to whom correspondence should be addressed (telephone 34-976761873; fax 34-976762388; e-mail cnerin@unizar.es).