Antimicrobial Packaging

Antimicrobial packaging is one of the most promising versions of an active packaging technology, and antimicrobial food packaging materials interact with the food or headspace of the package to reduce, inhibit, or retard the microorganisms present in food or in packaging material by extending the lag phase and reducing the growth rate of microorganisms in order to extend shelf life and maintain the product quality and safety (Suppakul et al., 2003a; Han 2000; Appendini and Hotchkiss, 2002).

Antimicrobial (AM) packaging technology can be applied by several methods:

  • • Addition of sachets/pads containing volatile antimicrobial agents in to the packages. No direct surface contact occurs and volatile antimicrobials are released in to the headspace of the package to retard the growth of pathogenic or spoilage bacteria.
  • • Incorporation of volatile or nonvolatile antimicrobial agents directly into the polymer by extrusion, heat press, or casting.
  • • Coating or adsorbing antimicrobials onto the polymer surfaces. Coatings and dips serve as carrier of antimicrobial compound and are in contact with food surface.
  • • Immobilization of antimicrobials to polymers by ion or covalent linkages.
  • • Use of polymers like chitosan that are inherently antimicrobial (Appendini and Hotchkiss, 2002).

The effectiveness of AM packaging is greater compared to direct addition of preservative agents into food because AM agents added on food surfaces by sprays or drips are not effective enough to inhibit microorganisms. But the attachment of AM agents with polymer film enables slow and continuous release of AM agents from packaging material to food surfaces, which enable AM agents to maintain high concentrations over a long period. Also, AM activities of preservative agents may experience inactivation (such as neutralization, hydrolysis, dilution, etc.) by food matrixes and components when added directly into the food (Appendini and Hotchkiss, 2002; Muriel-Galet et al., 2012). Besides, direct addition of preservative agents into food can reduce the food quality by changing the organoleptic and textural qualities of the food. Thus, AM packaging plays important roles in inhibiting the growth of targeted bacteria on foods while improving food safety and prolonging shelf life without sacrificing food quality (Sung et al., 2013).

Troublesome spoilage microorganisms in dairy products include aerobic psychro- trophic Gram-negative bacteria, yeasts, molds, heterofermentative lactobacilli, and spore-forming bacteria. Antimicrobial packaging can be used to prevent the growth of undesirable and spoilage microorganisms and extend the shelf life of dairy products (Ledenbach and Marshall, 2010; Lecura et al., 2012).

In antimicrobial packaging technology, antimicrobial packaging material can be created by using chemical antimicrobial agents or natural antimicrobial agents. But the trend in antimicrobial packaging is to use natural agents because of increasing consumer demands for safer and more natural foods.

 
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