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Sustainable Coating for Food Packaging based on Starch and Seaweed Extracts

Final Report Summary - PLANTPACK (Sustainable Coating for Food Packaging based on Starch and Seaweed Extracts)

Executive Summary:

INTRODUCTION:
The food supply sector relies on packaging to provide a physical barrier between the food product and the external environment ensuring hygiene and protection from physical, chemical and biological agents, thereby enhancing the shelf life of the product. However, packaging technology has to balance food protection with increasing environmental pressures and tightening packaging regulations on municipal disposal. Food packaging waste (around 45 million tonnes per year in Europe) represents 60% of all packaging by volume produced in developed countries, and over one third of this goes to the consumer household bins and ends up in landfill.
Existing products for the application of paper and board food packaging have a number of limitations. The most common materials used are based on petrochemical derived polymers due to their favourable functionality characteristics, such as good tear strength and barrier properties.
However, their dependency on oil along with increasing costs is making the food packaging sector vulnerable. There is an increasingly strong market drive for food packaging to be derived from sustainable resources, particularly for coatings. The potential to recycle or compost paper/card packaging after use is limited due to petroleum derived coatings which inhibit the processes. Other coating materials are causing health concerns. In particular, perfluorooctanoic acid (PFOA) coatings,which are extensively applied to paper food packaging to provide grease resistance, have been linked to cancer, reproductive problems and immune disorders. However these compounds are still in use by the fast food industry.
The implementation of the European Directive on Packaging and Packaging Waste (94/62/EEC), the Packaging Regulations (2003), and an increase in consumer concern for the environment are promoting the recovery, recycling and/or composting of paper packaging. Although recycling of food packaging (derived from plastics or paper/paperboard coated with plastics) is currently achievable, it is a difficult and expensive process. Food packaging materials usually consist of a large number of different types of polymer each of them containing different processing additives such as fillers, colorants and plasticisers. Paper/paperboard packaging material may be coated or multi-layer composite of different polymers for better performance. Wax-coated paper packaging materials often renders recycling uneconomic, (mainly as a consequence of requiring multiple processes and very specialist equipment) making disposal to landfill a more convenient alternative.

Project Context and Objectives:
The main objective of the PlantPack project is to develop a sustainable, natural food packaging coating product derived from seaweed and starch, which will be applied to paper and cartons in the form of a spray coating. The coating is intended to replace the current petroleum derived coatings at a more competitive cost. The final product will also be both recyclable and compostable, thus providing an all-round disposal option. The new packaging will have the appropriate symbols to clearly show the consumer their disposal options.

There are a number of scientific, technological, societal and policy, and also economic objectives for the project including the enhancement of the current understanding of the effects of combining seaweed extracts and starch on mechanical parameters of food packaging coating for paper wraps and cardboard; to study the relationship between the relative proportions of seaweed extract and starch and brittleness, strength and barrier properties of the developed coating applied to paper and cardboard; to develop an aqueous solution spray coating of seaweed extracts and starch that will adhere to paper and cartons; to reduce the plastic waste in landfill in the coming years and to improve the recycling and composting of coated paper.

Technical Objectives
1. Develop a coating formulation containing seaweed extract, starch with a viscosity in the range 100 to 500 centipoises (cPs).
2. Development of an aqueous solution spray coating of seaweed extracts and starch that will adhere to paper and cartons having a minimum adhesion strength of 450 g/cm2.
3. Development of a packaging material that will be water resistant and have a CO2 permeability of
3.5x10-15 mol m/m2 sPa, O2 permeability of 3x10-16 mol m/m2 sPa, and a lipid retention of <1% w/w.

Societal and Policy Objectives
4. Reducing cases of food poisoning by at least 5% by providing a safe food storage environment.
5. Reducing the plastic waste in landfill in the coming years and to improve recycling of coated paper Suitable packaging products produced, tested and complies.
6. Increasing user green-satisfaction by enabling domestic disposal (composting) Economic Objectives:
7. Development of biodegradable paper packaging coating technology derived from natural products at a maximum price of 2€cents/m2
8. Development of recyclable and biodegradable carton/paperboard food packaging derived from natural resources at a maximum price of 10 €cents/m2The main objective of the PlantPack project is to develop a sustainable, natural food packaging coating product derived from seaweed and starch, which will be applied to paper and cartons in the form of a spray coating. The coating is intended to replace the current petroleum derived coatings at a more competitive cost. The final product will also be both recyclable and compostable, thus providing an all-round disposal option. The new packaging will have the appropriate symbols to clearly show the consumer their disposal options.

Project Results:
Description of the main results achieved:

Significant Results in Work Package WP1: (see also Deliverable Reports D1.1 D1.2 and D1.3)

- Seaweed extracts, starch and combinations of polysaccharides are all in use in the food, cosmetic and pharmaceutical industries. This project focuses on a coating that is sustainable and can be applied to paper or paperboard to provide a coating which has adequate properties to conform to the substrate with good barrier properties.

- The results achieved in Work Package WP1 includes information about emerging research and state of the art of the knowledge on interactions arising when seaweed extracts and starch have been used in edible barrier coatings in food packaging. Substantial information is available about seaweed extracts and starch hydrocolloids. It is important to obtain a clear understanding of their chemical properties to obtain homogenous coatings.

- Ideal formulations contain a ratio of 50:50 or above for the modified starch:seaweed extract. The information obtained from completing tasks T1.1 T1.2 T1.3 and T1.4 has provided a foundation of understanding and formulations which balance the viscosity, thickness, mechanical properties and grease resistance of a number of coatings.

- Milestone MS1 and Result No 1 have both been achieved and a number of starch and seaweed coatings have been identified. They consist of the unmodified native starch in combination with either sodium alginate (Na alginate) or a commercially available carrageenan blend. Various ratios were examined and further details can be found in the 3 Deliverable Reports for WP1.


Significant Results in Work Package WP2: (see also Deliverable Reports D2.1 and D2.2)

- One of the challenges is to design a blend of polymers which improve the biodegradable characteristics of polylactic acid. It is well documented in literature that PLA requires special composting at high temperatures for degradation to occur. Polyvinyl acetate was selected because it fits the criteria of being a biodegradable polymer. Three different grades were blended with PLA 4060D. Laboratory analysis of a range of formulations was carried out to determine their viscosities. This gave an indication of the extent of flow at a shear rate of 9038s-1, which can be correlated to the forces applied during application with a spray gun. This will be investigated at a later stage of the project.

- Samples were formulated and the wet densities were measured using the pyknometer method. The densities for the formulations containing the unmodified maize starch with the Na alginate or unmodified maize starch with the Carrageenan blend ranged between 1.02-1.06. The slight variations were due to the ratio of powders added to the formulations. The unmodified starch used in this experimental work is denser than the selected seaweed extracts. The differences in the molecular weights can account for this variability.

- Formulations were cast into petri dishes and left to dry and form coatings in a controlled environment room set at 23oC and 50% relative humidity. After 48 hours the coating samples were dry. The thicknesses were measured using a Mini Test 4100 microprocessor thickness gauge fitted with a FN2 dual probe. Due to differences in the viscosities the thicknesses ranged between 40 - 250µm. Thinner samples were obtained when the viscosity was less than 60mPas for coatings comprising of unmodified starch with Na alginate. A viscosity of less than 40mPas was obtained for the formulations containing unmodified starch and the carrageenan blend. A number of coatings containing a starch:carrageenan blend gave good resistance. With further optimisation these coatings can give improved barrier properties.

- Milestone MS2 and Result No 2 have both been achieved by the establishment of the process set up and know how in production of coatings.


Significant Results in Work Package WP3: (see also Deliverable Reports D3.1 and D3.2)

- Both laboratory and pilot scale spraying equipment were used and the process variables and parameters were evaluated in order to obtain coatings on paper and paperboard samples with appropriate properties in terms of water and grease resistance. Laboratory scale spraying was carried out with an airspray system using a gravity handheld spraygun attached to a compressed air pipeline and using a nozzle size of 1.5 mm according to PRA recommendations.

- Pilot scale spraying was carried out using an airless air-assisted system. The system comprises an automatic sprayer booth (1VE-S, Maurimacchine, Italy) with 4 air-assisted airless spray guns (Aircoat GA 4000ACIC, Wagner, Germany). The fluids were transferred to the spray guns by means of a pneumatic piston pump (VVA 75-160, Valver, Spain). The spray system includes 3 online heaters.

- In this type of atomisation system the spray pattern is determined by the type of the nozzle (size and angle) and therefore can only be modified using a different nozzle. Moreover, the size of the droplets are related to the nozzle size, fluid pressure and viscosity (figure 11).

- Coated paper and board samples were dried based on the Standard UNE EN 20187: 1994 “Paper, board and pulps. Standard atmosphere for conditioning and testing and procedure for monitoring the atmosphere and conditioning of samples”. All the developed samples were dried by using a climatic chamber VOTSCH (VC 2020) and they were maintained at 23ºC, 50 % RH for 24 h following standard method recommendations. These conditions allowed a comparison of the properties obtained in all the samples in terms of thickness, weight, mechanical and barrier properties as described in Deliverable D3.2. Relating to the industrial scale, the drying process could be improved for each of the different samples being faster in the solutions based on ethyl acetate. In relation with water based coatings, the drying process at industrial scale can be improved by applying higher temperatures around 40-50ºC.

- Water barrier characteristics of paper and paperboard samples determined by water absorption (COBB) measurements and wetting properties such as contact angle analysis were improved by PLA coatings. The improved water barrier properties of paperboard samples can be exploited in the preparation of water-resistant boxes for storage and distribution of high moisture foods. On the other hand, samples coated with Starch/Na alginate solutions showed a good grease resistance that is suitable for fatty foods like hamburgers, cheese and jam. In terms of mechanical properties, all the coated samples presented lower values of Young´s modulus (E) indicating a plasticiser effect of the coating that is justified by an increase of the elongation at break values improving the elasticity of the material. In terms of SEM analysis (Scanning Electron Microscope), homogeneous coatings have been achieved, being better in samples coated at pilot scale.

Milestone MS3 and Result No 3 have both been achieved by the formulation of starch and seaweed based paper and paperboard food-safe packaging with optimised barrier properties.

Significant Results in Work Package WP4: (see also Deliverable Reports D4.1 to D4.4)

The results on recyclability show that the PlantPack coatings in the study slightly reduce the disintegration of the paper and board fibres and therefore augments the percentage of rejects. Moreover, the PlantPack coatings in the study and especially those including PLA cause slight increases in tensile strength of paper samples. Similar tear strength levels were observed between coated and uncoated paper and paperboard samples. Finally, results did not reveal significant changes in optical properties.

Regarding the compostability studies the following conclusions can be reported:

- Disintegration: PlantPack coated paper samples disintegrated in less than 4 weeks in simulated compost environment what represents a reduction in time with respect to PE coated papers. PlantPack coated paperboard samples achieved a disintegration degree of more than 60% after 12 weeks in composting conditions. The higher thickness of the paperboard substrate in comparison with paper substrate could be responsible of its lower disintegration.
- Biodegradation: PlantPack coated samples biodegraded around 50%-60% after 80 days in compost medium. This percentage increased for the paper sample coated with starch/Na alginate up to 80%. Biodegradation test will continue up to 6 months as established in the standard.
- Ecotoxicity: Composts resulting from the disintegration of PlantPack samples did not show any ecotoxic effect in Lepidium sativum, except for the mixture 50RS:50C containing PLP2 compost.
In summary, the PlantPack coating materials studied are in general aligned with the requirements associated to paper and paperboard recycling and composting.

- The objective of Deliverable D4.2 was to compile the relevant legislation for the verification of the compliance of PlantPack paper and paperboard intended to come into contact with food. In order to verify the compliance of the target coated packaging materials, substances subject to restrictions and requirements are listed in the present report. The standards (if applicable) to verify the applicable restrictions and requirements are included as well.
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Considering the complete migration of the different substances, all them are under the SML (Specific Migration Level) regarding the Starch/Na alginate formulation. On the other hand, the results for the coatings concerning the PLA/PVAc formulation show that all the substances exceed their SML in all the substrates tested, as well as the OML (Overall Migration Level). However, it is necessary to point out that it has been theoretically calculated assuming the worst case, supposing that all the substances of the coating subjected to restriction migrated to the foodstuff. Consequently and, insomuch the residual content screening approach delivers not suitable results, it was necessary to proceed with further migration testing based on laboratory analysis, in order to confirm or reject these assumptions.
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Regarding the experimental work carried out with the PLA/PVAc formulation, the results obtained confirm that:
- The amount of lactic acid (moomer) that has migrated from paperboard coated samples exceeds the SML. Consequently, this substrate is not suitable for PlantPack PLA/PVAc coating. On the other hand, migration extracts from coated paper samples presented amounts of lactic acid lower than SML established in Regulation (EU) 10/2011 indicating the suitability of this material for food packaging applications (simulant EtOH 10% (v/v)).
- When analysing the coated paper and paperboard samples of PlantPack, acetaldehyde and vinyl acetate were not detected in any of the samples (in any of the three simulants studied).

- Regarding the residual solvent quantification, after the analysis of the obtained results, it is possible to conclude that none of the analysed samples exceeded the legal SML of 10 mg dm-2 regarding ethyl acetate established in Regulation (EU) 10/2011.
Milestone MS5 has been achieved by the demonstration of the recyclable, biodegradable and usage characteristics of the PlantPack packaging.

Significant Results in Work Package WP5: (see also Deliverable Reports D5.1 and D5.2)
- The production trials carried out at Yanko SP. Z O.O. in May 2014 allowed for the integration of the various technology components in an actual industrial production environment. The application of the PlantPack coating onto paper & board food packaging using a flexographic printing machine meant that the technology integration was effectively carried out on this printing machine. The application of the coating onto the paper packaging was by one of the rollers on the printing machine fed by gravity from a hose connected to a large container.

- The Deliverable Report D5.2 presents the work completed for a desk top study that has been undertaken to review the feasibility for the design and construction of a pilot scale plant post project.

- It also explores the possible environmental, economic and societal benefits and impacts of the PlantPack sustainable coatings for food packaging based on starch and seaweed extracts.

- In addition to the above, in Annex I of this D5.2 we have reported on the identification, quantification, evaluation and prioritisation of environmental aspects in relation to the PlantPack technology using the (simplified) Life Cycle Assessment (LCA) tool. This SLCA of the new materials developed in PlantPack project has been performed using a methodological framework based on a simplified perspective of ISO (International Organization for Standardization) LCA recommendations, according to the requirements defined by UNE 150041:1998 EX - Simplified Life Cycle Assessment.

- The initial designs for the PlantPack pilot scale plant (or ‘Reactor’) were previously reported in Deliverable Report D2.2 which included a proposed Process Flow Diagram, Process and Instrumentation Diagram (P&ID) and an outline Technical Specification.

Significant Results in Work Package WP6: (see also Deliverable Reports D6.1 to D6.4)

- The improved water barrier properties of paperboard samples can be exploited in the preparation of water-resistant boxes for storage and distribution of high moisture foods. On the other hand, samples coated with Starch/Seaweed extract showed a good grease resistance that is suitable for fatty foods like hamburgers, cheese and ham for example. Regarding the sustainability results, PlantPack coated samples are aligned with the requirements associated to paper and paperboard recycling and composting.
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The work which Deliverable Report D6.1 relates to is the quantitative analysis of the prototype system. In practise the application and testing of the two PlantPack coating strategies on to food packing paper was carried out using flexographic printing machines at project partner Yanko SP. Z O.O. in Rzeszow, Poland.

- A number of application trials on both of the two PlantPack coatings were carried out to determine the overall performance and repeatability of testing and the results using the ‘strategy 1’ coating using starch and seaweed extracts were particularly successful. As previously reported in the ‘Confidential’ Deliverable Reports D1.3 and D2.1 the strategy 1 formulation is the grease-resistant coating and the ‘strategy 2’ coating is the moisture-resistant coating.

- The work in Deliverable Report D6.2 relates to the techno-economic analysis of the PlantPack coating. A quantitative analysis of the technical and economic values of the two new coatings (grease resistant and water resistant) has been completed in this Deliverable where deposition rates, volume of coatings, the manufacture of the coating blends and raw material availability and future proofing (sustainability) are reported.

Milestone MS6 ‘Demonstration of the PlantPack system’ and Result No. 3 ‘Seaweed-based food packaging coatings’ have both been achieved by the work completed in Work Packages WP4, WP5 and WP6 and as reported in the associated Deliverable Reports.

Significant Results in Work Package WP7: (see also Deliverable Reports D7.1 to D7.5)

- A draft dissemination plan (D7.1) in RP1 and also a final dissemination plan at the end of the project (D7.3) have been developed identifying dissemination opportunities, potential routes to market and marketing measures to advertise the PlantPack technology to the public.

- A technology assessment and prior art search has been conducted with the aim to confirm exploitable foregrounds. From this initial assessment, a detailed IPR strategy was developed and reported in the Deliverable Report D7.2 “Protection of IPR”.

A website for the PlantPack project was established within the first 2 months of the project in Reporting Period RP1: http://www.plantpack.eu. The project logo was agreed by all the partners present at the Kick-off Meeting hosted by PRA at Hampton, UK.

The general public can access the Home page and also the Consortium page, Contacts page and News&Events Page. Access to the File Store is limited by password entry to the Project Partners.

The project website has been updated at least every 3 months by the project Coordinator and the File Store will be used for the downloading of Meeting Agendas, Minutes, Deliverable Reports, and Dissemination materials etc.

- The Deliverable Report D7.4 ‘Video clip and dissemination materials’ has reported on the production of 3 project videos and also on all of the dissemination materials produced throughout the duration of the project.

Significant Results in Work Package WP8 (Consortium Management) - see also Deliverable Reports D8.1 and D8.2:

- Coordination of technical activities.

- Continued risk management.

- Communications Management and Administration including the G.A. and C.A.

- Management of reporting periods RP1 and RP2, collation of Deliverables and Milestones.

- Organisation of all quarterly technical, exploitation and management meetings.

Potential Impact:
The food packaging sector in Europe represents around 50% of turnover of the whole packaging sector, and in 2006 was valued at €17.8billion and consists of more than 28,000 companies of which 99.1% are SMEs. Food packaging is essential to providing a physical barrier to protect the food products from external harm. The food industries within the eight countries that became member states of the EU in 2004 had sales growth of 72% between 2001 and 2006. Comparative growth in the packaged food market of the original 15 EU member states was recorded at 63%. In Europe, the share of food packaging averaged 55% of the global packing industry.

During the period of 2010-2015, packaged food and drink consumption in Europe is projected to grow by 2% per annum, to exceed an annual volume of 864 billion packaging units by 2015 (80 billion more than in 2010) . Within the paper and board packaging market, Europe has 11 countries in the top 25 consumers of this product and consumes in excess of $50 billion worth per annum.

The most common materials used in food packaging are based on petrochemical derived waxes and polymers, due to their functionality performances and availability in bulk quantities. However, with increasing petroleum costs and recent instability and volatility in some oil producing countries, the food packaging sector is searching for a reliable, sustainable coating technology, with equal or improved functionality to existing products, and one that will promote the recycling potential of spent food paper packaging containers, (currently this is difficult, as petroleum/wax based coatings on packaging inhibit paper recycling potential). Currently, 34.4 million tonnes of food packaging waste ends up in landfill each year in Europe. This is in part due to difficulties in recycling current food packaging waste. In addition, food producers handling more than 50 tonnes of packaging materials a year and with greater than €2 million turnover, must comply with recycling targets.

The amended 94/62/EC Directive on Packaging and Packaging Waste sets a global recycling target of 60% for paper packaging waste in Europe by 2015 - this a powerful driver for PlantPack; currently only around 49% of all paper packaging is recycled, however Europe recycles less than 29% of food waste packaging. Finally, feedback from fast-food outlets has confirmed a strong market drive for food packaging coatings to be derived from sustainable resources. Currently, there is no such sustainable coating technology available for the food packaging sector that meets our needs.

In 2007, there were an estimated 17,000 fast food outlets in Europe. Individual operators and turnovers are detailed in the table below. In 2009, the UK fast food industry alone grew by 8% and expected increases in Germany of 1% per annum . These increases include large international franchises and small independent outlets.

Unfortunately, the majority of packaging from the fast food industry ends up in landfill. Research into McDonald’s outlets in Finland found that only 29% of packaging waste was being recycled . In addition, these companies are facing increasing costs of existing packaging solutions that rely on petroleum product coatings. PlantPack will produce a sustainable, biodegradable product, as a solution, the PlantPack product will be recyclable, but in the unfortunate circumstances it ends up in landfill, it will break down more rapidly than other packaging solutions due to its biodegradability characteristics.

List of Websites:
A website for the PlantPack project was established within the first 2 months of the project in Reporting Period RP1: http://www.plantpack.eu and is also reported in more detail in Deliverable Report D7.5.

The project logo was agreed by all the partners present at the Kick-off Meeting hosted by PRA at Hampton, UK. The general public can access the Home page.The PlantPack Website is password protected so that only the Consortium Beneficiaries can access the File Store (see above). The File Store is used for the downloading of Meeting Agendas, Minutes, Deliverable Reports, Dissemination materials etc.

The PlantPack website will be promoted to ‘euronews.net’ as a possible subject of an innovation story. Euronews are presently making a series of 3-minute features entitled ‘Innovation’ featuring SMEs that are partnering in EU Research Projects. The programme is supported by DG Research in Brussels.