Biodegradable high-tech packaging for cheese and pasta
Food preservation methods have been used by human beings since the dawn of time to keep foods safe and fresh for consumption for longer. Deterioration of fresh pasta and cheese products due to temperature and relative humidity will immediately affect taste and appearance and limit product shelf life. A controlled atmosphere, antimicrobial effects and a selective gas barrier are required to address these problems. The EU-funded BIO4MAP (Transparent and high barrier biodegradable film and sheet for customized modified atmosphere food packaging) initiative was tasked with developing a biodegradable, multilayer, flexible and transparent material for packaging fresh pasta and cheese. Partners worked to make this material by combining polylactic acid (PLA) and polyvinyl alcohol (PVOH) – two different biodegradable thermoplastic materials. Researchers exploited the differences in permeability between traditional packaging materials and BIO4MAP’s proposed ones to optimise gas combinations and obtain fully biodegradable packages. They developed a new biodegradable thermoplastic tie-layer based on the modifications of PLA and PVOH. The team reformed the low-cost commercial PVOH with plasticisers to achieve a thermoplastic PVOH. They then developed this polymer and placed it as the inner layer of the package to provide the oxygen barrier properties. BIO4MAP processed the best compounds they had previously produced at a plastics pilot plant to produce sheets. The researchers measured the mechanical and barrier properties of the sheets to identify those with the best characteristics. The researchers developed PVOH grades that were adapted perfectly to the cast-sheet extrusion equipment. BIO4MAP had developed transparent and homogeneous sheets with mechanical properties similar to Hi-Selon. To develop natural wax-based coatings, BIO4MAP identified olive leaves as a promising raw material to ensure a water vapour barrier. Scientists extracted the materials needed by developing a process to evaluate the characteristics and especially the water vapor properties of the obtained waxes. With the wax yields being lower than expected, researchers used wax from olive leaves to develop a proof of concept at the lab scale. The researchers used commercial wax to develop a pilot-scale formulation for coatings and to produce packaging samples. These new packages will allow easy recyclability of PLA due to its effortless separation from PVOH.
Keywords
Biodegradable, cheese, pasta, packaging, food preservation, BIO4MAP
