532 Novel food packaging techniques energy than the 29 megajoules needed to manufacture lkg of fossil-fuel-based polyethylene. This finding prompted Monsanto to terminate this method of producing PHA. The Biopol assets were obtained by Metabolix but food packaging is not a product line they intend to focus on in future. Proctor and mble together with Kaneka Corporation are working on a new development in PHa production but this product might not become available in large quantities until 2005 24.5.4 PLA in food packaging With Pla it is a similar story in terms of energy balance to PHA when one looks at the production site of Cargill Dow with its Nature Works PLA in Blair, Nebraska. The Blair plant with a capacity of 140 000 metric tons per produces lkg PLa with 56 megajoules of energy. However, in principle PLa processes can require between 20-50% fewer fossil resources than making plastics from oil but it is still significantly more energy intensive than most trochemica Packaging solutions from Nature Works can be extruded, thermoformed and blow moulded, unlike other traditional products, such as paper. For packaging ey have two film grades and one grade for thermoforming. The film gra designed for applications like candy twistwrap and for laminations for packaging such as flavoured crewels, coffee packs and pet foods because of the additional advantageous properties such as the barrier to flavour and grease and superior oil resistance. The potential applications of thermoformed products within packaging is multifold, dairy containers, food service ware, transparent food containers, blister packs and cold drink cups. PLA polymer has been shown to biodegrade similarly to paper under simulated composting conditions (ASTM D5338, 58%C). Degradation of PLa packaging depends both on exposure conditions and on amount and type of plasticiser. Sainsbury would like to use PLA but will not do this because of the lactic acid coming from GM crops. I The consumer might not accept this at the moment although the gm label is destroyed at the fermenting stage. Much of the PLA of Cargill Dow is for fibre applications but the company is already working with many leading Europear packaging converters, including Trespaphan on oriented PLA films, Klocknes pentaplast on thermoformed trays and lids, and Autobar on thermoformed dairy pots. Food retailers are also increasingly involved 24.5.5 Proteins in food packaging Proteins have long and empirically been used to make biodegradable, renewable, and/or edible packaging materials. Numerous vegetable proteins(corn zein, wheat gluten, soy proteins) and animal proteins(milk proteins, collagen, gelatine, keratin, myofibrillar proteins) are commonly used. Although protein materials have been studied extensively a breakthrough is not yet imminent although some of the properties have increased extensively recently. Proteinenergy than the 29 megajoules needed to manufacture 1kg of fossil-fuel-based polyethylene. This finding prompted Monsanto to terminate this method of producing PHA. The Biopol assets were obtained by Metabolix but food packaging is not a product line they intend to focus on in future. Proctor and Gamble together with Kaneka Corporation are working on a new development in PHA production but this product might not become available in large quantities until 2005. 24.5.4 PLA in food packaging With PLA it is a similar story in terms of energy balance to PHA when one looks at the production site of Cargill Dow with its Nature Works TM PLA in Blair, Nebraska. The Blair plant with a capacity of 140 000 metric tons per year produces 1kg PLA with 56 megajoules of energy. However, in principle PLA processes can require between 20–50% fewer fossil resources than making plastics from oil but it is still significantly more energy intensive than most petrochemical processes. Packaging solutions from Nature Works can be extruded, thermoformed and blow moulded, unlike other traditional products, such as paper. For packaging they have two film grades and one grade for thermoforming. The film grades are designed for applications like candy twistwrap and for laminations for packaging such as flavoured crewels, coffee packs and pet foods because of the additional advantageous properties such as the barrier to flavour and grease and superior oil resistance. The potential applications of thermoformed products within packaging is multifold, dairy containers, food service ware, transparent food containers, blister packs and cold drink cups. PLA polymer has been shown to biodegrade similarly to paper under simulated composting conditions (ASTM D5338, 58ºC). Degradation of PLA packaging depends both on exposure conditions and on amount and type of plasticiser. Sainsbury would like to use PLA but will not do this because of the lactic acid coming from GM crops.21 The consumer might not accept this at the moment although the GM label is destroyed at the fermenting stage. Much of the PLA of Cargill Dow is for fibre applications but the company is already working with many leading European packaging converters, including Trespaphan on oriented PLA films, Klo¨cknes pentaplast on thermoformed trays and lids, and Autobar on thermoformed dairy pots. Food retailers are also increasingly involved. 24.5.5 Proteins in food packaging Proteins have long and empirically been used to make biodegradable, renewable, and/or edible packaging materials. Numerous vegetable proteins (corn zein, wheat gluten, soy proteins) and animal proteins (milk proteins, collagen, gelatine, keratin, myofibrillar proteins) are commonly used. Although protein materials have been studied extensively27 a breakthrough is not yet imminent although some of the properties have increased extensively recently. Protein 532 Novel food packaging techniques