PROJECT DESCRIPTION
BACKGROUND
Lacquers for food packaging are mainly derived from petroleum, with epoxy resin being the most widely used component. Using a petrol-based lacquer increases the carbon footprint of a packaging company by 0.4% for each kilogram of metallic cans produced; 90% of this impact is linked to the production of the epoxy resin that causes 3.31 g of carbon dioxide emissions per kilogram of cans. Some efforts have already been made to introduce into this process components or additives from renewable sources. BIOCOPAC, an earlier LIFE project led by the same beneficiary, worked on the development of a natural lacquer from tomato processing by-products for application on the interior and exterior surfaces of cans used for foodstuffs.
OBJECTIVES
Following on from the BIOCOPAC project, LIFE BIOCOPACPlus set out to demonstrate that a bio-lacquer made using cutin, a water-repellent (a biopolymer), found in waste tomato skins, can be cost-effectively produced on an industrial scale. The lacquer will serve as a coating for food contact applications in metal cans. The project was designed to give value to tomato industry by-products, by offering alternative strategies for waste reuse and minimisation in accordance with the Waste Framework Directive. As well as designing, building and optimising the operations of the prototype plant, it would scale up the extraction process of cutin and the formulation of the bio-lacquer; and find the best storage conditions for cutin to guarantee continuous production. Additional objectives were to conduct a lifecycle assessment of the new eco-cans, demonstrate compliance with EU food contact regulations at the end of the cans' shelf life, and analyse the economic potential of other uses of the tomato skins (such as to generate bio-energy).
RESULTS
The LIFE BIOCOPACPlus project demonstrated that production of a tomato-based bio-lacquer can be scaled up from the laboratory to semi-industrial level. It produced 250 kg of cutin from around 5 tonnes of tomato skins. The cutin was polymerised and formed the main component ingredient of the lacquer, which was used to protect cans made of tinplate, tin-free steel and aluminium. A test run of 3 000 cans was manufactured using standard processing times and temperatures. The patented bio-lacquer was shown to meet the required functional and hygienic properties, indicating that it can be a substitute for existing commercial lacquers from non-renewable sources. Indeed, the new bio-lacquer also solves the problem of migration of dangerous synthesised substances from lacquer into food. The pilot plant was implemented using simple and well-known technologies without organic solvents, with high performance and yields at relatively low cost. A lifecycle assessment conducted by the project showed that in comparison with a standard lacquer of fossil fuel origin, CO2 eq emissions are 730 mg lower for each can. All the solid and liquid waste generated during manufacturing was reused to produce biogas. Based on these considerations, the process can be easily replicated in other contexts or countries, including tomato-processing companies that aim to have a locally sourced lacquer (zero mileage). The pilot plant was built on a farm, which shows the potential for differentiating farm activities, in line with regional and national policies, and creating new rural jobs. The possibility of producing an innovative and green can is a great opportunity to re-launch the humble can and build market share. Since September 2018, most epoxy resins have been banned at EU level from packaging in contact with infant formulas, follow-on formulas, processed cereal based food, baby food, food for special medical purposes developed to satisfy the nutritional requirements of infants and young children, or milk-based drinks and similar products specifically intended for young children. The new bio-lacquer can therefore find a market all over Europe. For tomato-growers and processors, there is the double advantage of a waste becoming a resource and a reduction in disposal costs. The project thus supports the implementation of the EU Waste Framework Directive and complies with the principles of the circular economy. Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).
