Composition of antimicrobial edible films and methods for assessing their antimicrobial activity: A review

Active packaging plays an important role in food and seafood preservation in the sector of food safety. The main role of antimicrobial packaging is to prohibit the bacterial and fungal growth. Biopolymers are the main film-forming materials which can be integrated with preservatives and antimicrobial agents, and the edible films containing the additives can be utilized as a substitute to maintain food products. Although different tests including disc and well diffusion assays, viable cell counts, vapor-phase technique, and optical density-based methods are used by microbiologists, no standard methodology has been firmly established to assess the antimicrobial effects of edible films. Hence, this review discusses the strengths and limitations of the published microbial methodologies used for assessing the activity of antimicrobial packaging. The type of active components and materials used to produce edible films are among the most fundamental aspects to select an appropriate evaluation method. Our findings revealed that the disc and well diffusion assays followed by the viable cell count methods are the most common methods for evaluating the antimicrobial activity of edible films.