Food packaging, biopolymers

Keywords Food packaging, biopolymer, nanocellulose, metal nanoparticle, polymer nanocomposite... 

Alginate is another biopolymer extensively studied for its gel formation property with applications in the food packaging and pharmaceutical industries as well as for membranes and as biosensors. Such LDH hybrid assemblies were recently used for the detection of cations such as Ca [HO]. 

Antimicrobial Edible films were prepared from natural fiber of pectin and other food hydrocolloids for food packaging or wrapping by extrusion followed by compression or blown film method. Microscopic analysis revealed a well mixed integrated structure of extruded pellets and an even distribution of the synthetic hydrocolloid in the biopolymers. The resultant composite films possess the mechanical properties that are comparable to films cast from most natural hydrocolloids that consumed as foods or components in processed foods. The inclusion of polyethylene oxide) alters the textures of the resultant composite films and therefore, demonstrating a new technique for the modification of film properties. The composite films were produced in mild processing conditions, thus, the films are able to protect the bioactivity of the incorporated nisin, as shown by the inhibition of Listeria monocytogenes bacterial growth by a liquid incubation method. 

An increased interest has been shown in the use of biopolymers as material for food packaging, and NMR was employed to study the physicochemical properties of plasticized com zein films.103 The elucidation of freezing effects in foodstuffs was approached by studying the interactions between amino acids, sugars, and alcohols at temperatures below 273 K.104... 

Modified polysaccharide biopolymers have found applications from permselective membranes to ionically conductive membranes for fuel cells. In this review, ionically selective membranes in particular will be explored. Recent studies and advances in using modified polysaccharides for food applications will also be reviewed with specific attention given to their potential uses in the development of active food packaging solutions, which include antimicrobial systems, coatings and bioactive compound delivery systems. 

Keywords Biopolymer, chitosan, active food packaging, membrane, permselective, antimicrobial, bioactive... 

Marjorie S. Austero is a MS Food Science/ PhD candidate in the Materials Science and Engineering Department at Drexel University, USA. She is currently working with the Natural Polymers and Photonics Groups and her current research is focused on biopolymer materials for use in filtration and active food packaging systems. 

Food packaging is another remarkable application of carbon nanotube composites. Usually, poor mechanical and barrier properties have limited the application of biopolymers hence, an appropriate filler is necessary for promoting the matrix properties. The unique properties of CNT have improved the thermal stability, strength and modulus, as well as the water vapour transmission rate of the industrially applied composites. 

In order to try to solve these environmental concerns, biopolymers are starting to emerge as an alternative to traditional synthetic polymers in the food packaging market. Oil-based polymers take at least 400 years to be completely degraded. However, biopolymers are fully biodegradable under certain atmospheric conditions in a few months, which avoids excessive accumulation in landfills. 

Starch is one of the most promising biopolymers for the production of food packaging trays for several reasons "" It is bio derived and fully biodegradable its cost is very low (0.7 /kg) and its production is abundant worldwide. Nevertheless, up to now the introduction of starch in the food packaging market has been restricted because it presents several drawbacks native starch,... 

The best-known renewable resources able to create biopolymer and biodegradable plastics are starch and cellulose [10,12]. Weber et at believed that the only biobased food packaging materials in use commercially on a major scale are based on cellulose [13]. 

Biopolymers satisfy environmental concerns, but they may have some limitations in terms of performance, such as heat resistance, barrier properties and mechanical properties associated with costs. Some PHA/PHB films may have increased fragility (due to high glass transition temperatures and melting temperatures), greater stiffness, less impact resistance and less heat resistance. All these factors are limiting the application of these films in food packaging. 

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