Active packages Antimicrobial properties

Some antioxidants possess antimicrobial properties, such as propyl gallate and butylated hydroxy anisole, which are somewhat effective against bacteria. Butylated hydroxy toluene has demonstrated some antiviral activity. Compatibility of antioxidants with the drug, packaging system and the body should be studied carefully. For example, tocopherols may be absorbed onto plastics ascorbic acid is incompatible with alkalis, heavy metals, and oxidizing materials such as phenylephrine, and sodium nitrite and propyl gallate forms complexes with metal ions such as sodium, potassium and iron. 

Chitosan is one of the natural antimicrobial agents that widely used in active packaging. It either incorporated directly or indirectly into the film matrix. Effect of CNF incorporation into starch/chitosan composite film towards antimicrobial properties was previously studied by Salehudin et al. (2014b). Starch/chitosan composite (S C 9 1) film was prepared with starch and chitosan only while starch/ chitosan nanocomposite film (S C 9 1 +2 %CNF) was prepared by adding 2 % of CNF, chitosan and starch. Significant enhancement on the antimicrobial properties and food shelf life for both films was observed. 

Edible films and coatings can be carriers of antioxidants (phenolic compounds such as butylated lydroxyanisole, propyl gallate, butylated hydroxytolene, tocopherol, citric acid, ascorbic acid, or natural compounds from heib extract) and antimicrobials (oiganic acids and their salts such as benzoic acid, soibic acid, propionic acid, chitosan, plant essential oil extracts, and so on.) to enhance their functional properties as active packagings (Janjarasskul and Krochta, 2010). Moreover, they can be carriers of nutrients, flavors, and colors to improve food nutritional and sensoiy quality. 

The active or intelligent packaging has various modes of action such as removal, Oj barrier, water removal, gas indicator, ethylene removal, CO release, antimicrobial properties, and so on. Recently, new films known as time temperature indicators have also been introduced for commercial application. 

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