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bioplasticsMAGAZINE_1305

Materials Films with

Materials Films with excellent barrier properties Oxygen transmission rate °C/50% RH Q 100 (cm 3 (STP) m -2 d -1 bar -1 ) 10000 1000 100 10 1 0,1 by: Elodie Bugnicourt Innovació i Recerca Industrial i Sostenible (IRIS) Castelldefels, Spain Markus Schmid Fraunhofer-Institute for Process Engineering and Packaging IVV Freising, Germany Permeability values of typical plastics, bioplastics and wheylayer Cellulose-acetobutyrate PE-LD EVA-copolymer, PE-HD PP (oriented) PC PUR-elastomer VAC 20% Celluloseacetate Wax/paper PA 12 PA 11 PVC-U PS (oriented) PA 12 PET (oriented) PVC-U (oriented) PA 66 PA 6 EVOH 44% PVDC EVOH 38% Wheylayer EVOH 32% EVOH 27% 0,01 0,01 0,1 1 10 100 1000 Water vapour transmission rate 23°C/85 0% RH Q 100 (gm -2 d -1 ) Fig 1: Barrier properties of whey-based layer vs. other plastics commonly used in the packaging industry normalised to 100 µm thickness [2] The authors wish to acknowledge the funding from the European Community‘s Seventh Framework Programme [FP7/2007-2013] for the research leading to these results under grant agreements n°218340-2 and 315743 through the WHEYLAYER and WHEYLAYER2 projects respectively. Fig. 2: Examples of applications for the Wheyalyer coated laminates: blisters and tubes (the packaging being currently tested) As published in issue 04/2011 of bioplastics MAGAZINE [1], more and more waste from food production plants is used as feedstocks for bioplastics, following a Maxi-use © strategy. Research is ongoing to improve the performance of such bio-sourced polymers, making them competitive with their synthetic counterparts and extending the range of applications that they can fulfill. In such a context the development of a biopolymer coating for multilayer plastic films, based on whey protein (which is able to replace current synthetic oxygen barrier layers used in food packaging such as ethylene vinyl alcohol copolymers or - EVOH) is expected to be far reaching in the market. Whey is a by-product of cheese manufacturing, therefore it does not enter into direct competition with other foods. Indeed, it is estimated that converting only 40% of the currently wasted excess (of 20 million tonnes annually in Europe) would cater for the global need to replace EVOH currently used in food packaging. The whey protein-based coatings developed in the Wheylayer project exhibited excellent barrier properties, outperforming most existing biopolymers (fig. 1). Since the publication of the aforementioned article, the study has continued with subsequent steps, including presenting the project’s findings to the industry and demonstrating the scale-up ability of the production as a preliminary requirement for its commercialization. Coated films were validated for storing various food products and the shelf life of the foods packaged with conventional films was compared with the whey protein film. In addition, the coated films and derived laminates have recently been converted in different formats of final packaging, either laminated tubes or thermoformed blisters (fig. 2). The developed wheycoating, which can be removed via enzymatic cleaning, allows multilayer films to become recyclable, and so represents a significant step in terms of cascade use before a final incineration or disposal. This, along with saving in emissions and energy, leads to a significant reduction in the environmental impact of packaging as shown by the life cycle assessment that was carried out. All in all, this new economical use of a bio-sourced by-product from the industry safeguards the performance of packaging and improves the use of resources throughout its life cycle, leading to tremendous advantages for this type of packaging compared with traditional plastics. www.wheylayer.eu References: [1] E. Bugnicourt, O. Mc Nerney, A. Lazzeri, “Maxi-use of wastes from agro-food processing to obtain truly sustainable bioplastics”, Bioplastics magazine, 04/11, Vol 6, p 32-34. [2] E. Bugnicourt, M. Schmid, O. Mc. Nerney, J. Wildner, L. Smykala, A. Lazzeri, P. Cinelli, “Processing and Validation of Whey-Protein-Coated Films and Laminates at Semi-Industrial Scale as Novel Recyclable Food Packaging Materials with Excellent Barrier Properties”, Advances in Materials Science and Engineering, vol. 2013, Article ID 496207, 10 pages, 2013 44 bioplastics MAGAZINE [05/13] Vol. 8

Materials Films with excellent barrier against mineral oils NatureFlex films, manufactured by Innovia Films (Wigton, Vumbria, UK), have been scientifically tested and proven to provide an effective barrier against mineral oil residues. This has been confirmed by a scientific study at the official Food Safety Authority of the Canton of Zürich in Switzerland. Why do we need protection from certain mineral oils? Potentially dangerous substances known as mineral oils have been found in packaging made from recycled paper fibres. Cardboard is produced using recycled paper including printed newspaper. Most commonly used newspaper inks contain mineral oils. These cannot be removed sufficiently during the recycling process and are thus able to enter cardboard food packaging, and can migrate into food. Mineral oil aromatic hydrocarbons (MOAH) are suspected of being carcinogens, according to the World Health Organization’s Joint Expert Committee on Food Additives (JECFA), and the UN’s Food and Agriculture Organization (FAO). Germany is well on the way to preparing a mineral oil law, which will quote a zero tolerance for MOAH in foodstuffs. In recent years much research has been carried out to understand how mineral oils are distributed in the environment and assess the risks they pose to human health. This has been a complicated area of study. Why are these films such good barriers? NatureFlex films are based on cellulose (a complex carbohydrate), with a high molecular-weight polar structure and small spaces containing water and softener. For these reasons, the solubility and diffusivity of nonpolar molecules such as mineral oils is low. Its mineral oil barrier protects food Mineral oil residues can migrate from the inner side of a contaminated primary pack such as a recycled cartonboard cereal box or a contaminated outer pack used to hold products during transportation. Contamination can even occur when packs are stacked closely together - on the supermarket shelf or in transit. As the world takes steps towards greater sustainability, protection of our wrapped products is the most vital aspect of this sustainability journey. “The tests conducted on our NatureFlex films showed that when used as the inner bag, flow-wrap or as a pouch they provide an excellent barrier against mineral oil residues. This is in addition to the standard oxygen and moisture barrier properties required by dried foods to ensure optimum product quality and maximise shelf-life” said Clare McKeown, Market Manager NatureFlex Films. MT www.NatureFlex.com Which film types provide a barrier to mineral oil? As leading market experts, Innovia Films can tailor its technology for specific needs and we are able to provide a barrier to mineral oils. The results of external laboratory testing have shown that there was no mineral oil breakthrough in any of the NatureFlex films range. Mineral oil breakthrough was observed for polyolefin films tested under the same conditions (OPP & PE), with breakthrough times of less than two months for uncoated OPP and less than one month for PE. PET and NatureFlex films were both found to be very good barriers to mineral oils. It was concluded that the NatureFlex films evaluated in the study gave an excellent barrier to mineral oils with a breakthrough time of greater than five years at room temperature. Months 72 60 48 36 24 12 0 Mineral Oil Barriers of Various Film Types at 25°C NatureFlex 30NK 28NP 23NVS OPP PE MOAH barrier testing of selected film types by Innovia Films and Kantonales Labor Zürich bioplastics MAGAZINE [05/13] Vol. 8 45

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