Poly(hydroxyalkanoates) for Food Packaging: Application and Attempts towards Implementation

Plastics are well-established for convenient and safe packaging and distribution of food and feed goods. At present, this special sector of the plastic market displays remarkably increasing quantities of its annual production. Caused by the ongoing limitation and strongly fluctuating prices of fossil feedstocks, classically used for plastic production, there is an evident trend to switch towards so-called “bio-plastics”. Especially for bulk applications such as food packaging, a broad implementation of “bio-plastics” constitutes a future-oriented strategy to restrict the dependence of global industry on fossil feedstocks, and to diminish current problematic environmental issues arising from plastic disposal. However, food packaging demands a great deal of the utilized packaging material. This encompasses tailored mechanical properties such as low brittleness and adequate tensile strength, a sufficient barrier for oxygen, CO2, and aromatic flavors, high UV-resistance, and high water retention-capacity to block the food´s moisture content, or to prevent humidity, respectively. Due to their hydrophobic character and the broad flexibility of their mechanical features, prokaryotic poly(hydroxyalkanoates) (PHAs) are considered as promising materials to compete with petro-plastics on the food-packaging market. Nevertheless, short-comings in particular aspects of their material performance and economics of their biosynthesis and purification constitute stumbling blocks on the long way towards broad implementation of PHAs for food packaging. This article discusses advantages and drawbacks of PHAs as food packaging materials, and demonstrates how desired properties can be improved by the designing of novel composite materials, and also encompassing techniques by applying nanoparticles.