Application of Edible Coatings Incorporated Avishan-e Shirazi (Zataria multiflora) Alcoholic Extract for Inhibition of Aspergillus flavus Growth on the Pistachio Kernel

Background: Antimicrobial packaging is a form of active packaging that could extend the shelf-life of foods and provides microbial safety for consumers. In order to control undesirable microorganisms on food surfaces, volatile and non-volatile antimicrobial agents can be incorporated into polymers. Incorporation of essential oils and other antifungal agents in edible films composition is an antimicrobial packaging that able to inhibit fungal growth on the pistachio and aflatoxins production. Objective: The antifungal activity of Avishan-e Shirazi (Zataria multifora) extracts against Aspergillus flavus in whey protein concentrate-based coating on pistachio kernels was investigated. Methods: The antifungal effect of Avishan-e Shirazi extracts was investigated in culture media by direct method (cup plate method) and application of whey protein concentrate (WPC) films as discs (disc deffusion method) incorporated with different concentrations of extracts. In order to evaluate the antifungal effect of extract in pistachio kernels coated with different concentrations of extract inoculated with a culture media discs contain 9-day-old growing A. flavus colony and the growth rate of inoculated discs were measured during 1 week. Results: In experimental condition, minimal inhibition concentration was achieved by 90 ppm of ahcoholic extract (30 percent concentration). The results also showed that WPC coating incorporated with 2500 ppm of Zataria multiflora extracts on pistachio kernels inhibited A. flavus growth totally. Conclussion: Regarding to application of importance of contamination with toxigenic fungi in pistachio kernel is suggested the application of Avishan-e Shirazi extract incorporated in edible coatings for toxigenic fungi growth and toxin production in foods.