title: Physical and Antimicrobial Properties of Starch-PVA Blend Films as Affected by the Incorporation of Natural Antimicrobial Agents.
abstract: In this work, active films based on starch and PVA (S:PVA ratio of 2:1) were developed by incorporating neem (NO) and oregano essential oils (OEO). First, a screening of the antifungal effectiveness of different natural extracts (echinacea, horsetail extract, liquid smoke and neem seed oil) against two fungus (P. expansumandA. niger) was carried out. The effect of NO and OEO incorporation on the films' physical and antimicrobial properties was analyzed. Only composite films containing OEO exhibited antibacterial and antifungal activity. Antibacterial activity occurred at low OEO concentration (6.7%), while antifungal effect required higher doses of OEO in the films. Incorporation of oils did not notably affect the water sorption capacity and water vapor barrier properties of S-PVA films, but reduced their transparency and gloss, especially at the highest concentrations. The mechanical response of the S-PVA films was also negatively affected by oil incorporation but this was only relevant at the highest oil ratio (22%). S-PVA films with 6.7% of OEO exhibited the best physical properties, without significant differences with respect to the S-PVA matrix, while exhibiting antibacterial activity. Thus, the use of OEO as a natural antimicrobial incorporated into starch-PVA films represents a good and novel alternative in food packaging applications.
authors.affiliation: Institute of Food Engineering for the Development, Polytechnic University of Valencia, Camino de Vera s/n, 48022 Valencia, Spain. amcaem@upvnet.upv.es.
authors.forename: Amalia
authors.initials: A
authors.lastname: Cano
authors.affiliation: Institute of Food Engineering for the Development, Polytechnic University of Valencia, Camino de Vera s/n, 48022 Valencia, Spain. mtchafer@tal.upv.es.
authors.forename: Maite
authors.initials: M
authors.lastname: Cháfer
authors.affiliation: Institute of Food Engineering for the Development, Polytechnic University of Valencia, Camino de Vera s/n, 48022 Valencia, Spain. dchiratld@tal.upv.es.
authors.forename: Amparo
authors.initials: A
authors.lastname: Chiralt
authors.affiliation: Institute of Food Engineering for the Development, Polytechnic University of Valencia, Camino de Vera s/n, 48022 Valencia, Spain. cgonza@tal.upv.es.
authors.forename: Chelo
authors.initials: C
authors.lastname: González-Martínez
keywords: A. niger; E. coli; L. innocua; P. expansum; mechanical properties; neem oil; oregano essential oil; water vapour permeability