18.2.1 Sustainability principles and eco-design strategies

In the paradigm of a sustainable society, food and beverage packaging needs to be able to improve the quality of human life whilst at the same time supporting the earth's eco-systems. Unfortunately, food packaging often contributes to environmental issues due to waste disposal problems. The public often perceive the impact of packaging materials on the environment as being far more significant than they actually are. But a reduction of the problem to the single issue of waste treatment could lead the package development process in the wrong direction. There is ambiguity and misunderstanding in the definition of sustainable food packaging. Given that it is widely understood that sustainability can be achieved by reconciling and meeting the requirements of environmental, social, and economic demands (Maxwell & van der Vorst, 2003; Jedlicka, 2009; Svanes et al., 2010), there is no reason why sustainable packaging could not also be possible through holistic consideration of these three dimensions (Svanes et al., 2010). With respect to environmental demands, natural resources should of course be dealt with appropriately in packaging manufacture and usage. With respect to social demands, welfare and safety of human communities should be taken into consideration in the application of food packaging. From an economic perspective, sustainable packaging must be viable in the present commercial world whilst allowing profits to be made by the producers. These three demands of sustainability are not mutually exclusive and can be mutually synergistic. Harmonizing these demands is essential for successful eco-design of food packaging.

There are many general guidelines and principles for sustainability covering agriculture, energy, waste generation and the environment, and food and beverage packaging sustainability should be understood as a part of these general principles. Among many general principles (Table 18.1), the work of the World Commission on Environment and Development is fundamental and globally accepted (Jedlicka, 2009). The World Commission defines sustainability as fulfilling the needs of the present without compromising the ability of future generations to meet their own needs. Therefore, any sustainability principles should be constructed for our descendants' needs as a persistent goal. This is one of the main criteria that must be considered in any assessment of a technological, commercial activity or product with regard to environmental impact. From the comprehensive life cycle assessment of a food packaging system and supply chain, it becomes evident that the environmental impact of a package itself is normally a very small fraction of the food packaging system, which in fact encompasses agriculture, food processing, retailers, consumers and waste handling (Williams et al., 2008; Davis & Sonesson, 2008; Roy et al., 2009). An analysis of milk and bread production has shown that the primary food production steps account for 60-80% of energy use, 60-95% of any global warming potential, and more than 95% of eutrophy as a percentage of the total figure from agriculture to retailer (Williams et al., 2008). For some exceptional scenarios and products (e.g., ultra high temperature (UHT) milk, or corn chips), packaging can have a higher proportion of the environmental impact of the total system (Horne & Grant, 2009). This analysis, as a general rule, emphasizes the importance of the protection function of food packaging. Prevention of food loss and waste is considered a primary factor of the eco-design of food packaging, and should be balanced with the adverse environmental impact of packaging itself. If we recognize that more energy is consumed to produce a food product than to fabricate its packaging, the environmental impact caused by the spoilage or waste of a product would be greater than that of any packaging waste. Thus, in the context of food packaging sustainability, packaging must still protect the contents properly. Even for products such as cereal snacks and tomato ketchup, where packaging takes a high responsibility for the environmental impact, the importance for sustainability of reducing food spoilage and waste by better packaging still exists (Roy et al., 2009; Horne & Grant, 2009).

Sustainable packaging thus means more than just the selection or change of packaging materials. It involves the holistic optimization of packaging design, based on a balanced perspective of the eco-system. The role and effect of packaging on the eco-system and its surroundings should be estimated correctly, and an appropriate packaging performance and waste reduction, with low environmental impact in the context of the whole system, should be sought.

Sustainability should, therefore, always be viewed as an holistic concept, taking proper account of the environment, society, economics and function (Maxwell & van der Vorst, 2003). Table 18.2 lists attributes that should be addressed when designing sustainable food packaging; any packages can only truly be sustainable when all these attributes are addressed in an equitable manner. It is not enough to confine the system boundary to the packaging material when designing food packaging: the entire food packaging system needs to be considered (see Figure 18.2).

Sustainable packaging could avoid or reduce environmental damage caused by human activities (e.g., climate change, land degradation, decline in water availability, etc.) and can be designed/achieved by using the four principles of effectiveness, efficiency, cycle and safety, as defined by the Sustainable Packaging Alliance (SPA) (Table 18.3) (Lewis et al., 2007). Thus, a packaging system should provide social and economic benefits throughout the food supply chain; it needs to be designed in a way to use materials and energy efficiently throughout the product life cycle; it should be optimized for packaging materials to be cycled continuously through natural or industrial systems; and the packaging components used in the system must be safe and not pose any harmful effects to human health or to the eco-system.

Eco-design of packages based on sustainability principles should consider the effect of the products on the environment at all stages of their life cycle (Chovet, 2010). Table 18.3 summarizes the major strategies for eco-design of food packages. Of course, even though these general strategies have been accepted within the industry, the strategies actually applied vary case by case and are dependent on the environmental impacts and specific circumstances related to each product packaging system. Both governments and industry have been involved in trying to encourage change: governments have enforced or promoted reduced packaging or recycling systems through legislation or benefit incentives; some companies have developed checklists or guidelines to promote the development of sustainable packaging (Verghese, 2008). Achievements and improvements have resulted from both small changes and great innovation of design and materials.

18.2.2 Assessment of eco-design

Several measures to evaluate the environmental impacts of packaging have been proposed, including global warming, energy consumption, ozone depletion, land use, eutrophy, airborne emissions, water-borne emission, solid waste production, etc. The most comprehensive measuring method is life cycle assessment (LCA) which quantifies inputs and outputs throughout the whole life cycle of a product in the eco-system. LCA consists of stages in goal and scope definition, inventory analysis, impact assessment and interpretation. There are several LCA methodologies differing in the impact categories adopted and their characterization (Parker, 2008; Bovea & Gallardo, 2006), and the results achieved may vary with the methods used and system boundaries applied.

While LCA is comprehensive and can produce accurate results, it needs a lot of data sets and requires many resources. Cheaper, quicker, and simpler methods are needed. For example, one simple tool based on the LCA approach is PIQET^TM (Packaging Impact Quick Evaluation Tool) developed by SPA. For a given packaging specification, PIQET^TM quickly calculates the global warming potential, cumulative energy demand, photochemical oxidation, water use, solid waste and land use in a web-based application. TOP^TM (Tool for Optimization of Packaging), developed by the Netherlands Packaging Centre (Gouda, Netherlands) with a group of 20 other companies, is a software tool for the optimization of packaging design. TOP^TM evaluates packaging using seven indicators: product-package combination, added value, logistic efficiency, heavy metals, reuse/recovery, material consumption and environmental effect. The MERGE™ (Managing Environmental Resources Guidance and Evaluation) tool designed by the Environmental Defense Fund (New York, USA) quickly screens packaging designs by calculating a quantitative profile of each design for 13 criteria or metrics: acute ecological hazard, chronic ecological hazard, dispersivity (dispersed into the environment in an unrecoverable form), volatile organic compounds content, missing data (i.e., sensitivity analysis), 'bad actor' chemicals, non-recyclable materials content, packaging resource consumption, packaging energy consumption, virgin materials content, packaging 'bad actors', packaging greenhouse gases and pallet inefficiency.

Carbon footprint is also often used as an indicator of environmental impact and represents the total greenhouse gas emissions caused directly and indirectly by the production of a product, expressed as the amount of CO₂ generated. Carbon footprint only accounts for global warming potential and ignores other insignificant impacts, but it is known to efficiently cover most of the environmental impacts of packaging and, thus, is a useful tool for assessing packaging from a sustainability perspective (Bovea & Gallardo, 2006). There has been a promotional move towards labeling carbon footprint on food packaging but it should be remembered that this labeling represents a CO₂ generation value for the food production and packaging processes as a whole.

The concept of a packaging scorecard to consider environmental effects has been proposed as a simple LCA tool. The most famous of these is the Wal-Mart Scorecard, which focuses on packaging sustainability, measuring the environmental performance of packaging from a retailer's perspective: greenhouse gas emissions from packaging production (15%), evaluation of material type for environmental friendliness (15%), product to package ratio (15%), cube utilization (15%), transportation impact of packaging materials (10%), recycled content (10%), recovery value (10%), renewable energy (5%) and sustainable innovations (5%). Another scorecard system proposed by Olsmats and Dominic (2003) covers supply chains from the supplier through transportation, distribution, and wholesale and retail sales to the consumer, using the categories of: machineability, product protection, flow information, volume and weight efficiency, right amount and size, han-dleability, other value-adding properties, product information, selling capability, safety, reduced use of resources, minimal use of hazardous substances, minimal amount of waste, and packaging costs. Svanes et al. (2010) formulated a holistic sustainable packaging design methodology consisting of five main indicators: environmental performance, total distribution cost, product quality preservation, market acceptance and user friendliness. While score-card systems are simple and identify potential improvements, they do not provide solutions but can only supply comparisons with alternatives.

18.2.3 Practical guidelines for eco-design innovation

Sustainable packaging is achieved by optimizing packaging systems. Any approach should be holistic and specific to products and situations. For example, large or bulk packaging is eco-friendly in most cases, but not always. Small, single portion packs would better suit the elderly and babies, who only consume a small portion size.

Sustainable packaging should also take consumer behavior and economic viability into consideration (Table 18.2). Readiness to return recyclable packages and sacrifice convenience for recycling is required for improved sustainability. Consumer education to better understand sustainable products is also required. The food supply chain could be redesigned to ensure efficient resource utilization and stock rotation. All these activities require an element of re-education at the individual, community, and society levels.

Economic viability is a very important element of sustainable packaging. Social or legal incentives to compensate the increased cost of possible sustainable packaging alternatives may elevate the competitive position of sustainable packaging in the market.

Reaching the optimal design for sustainable packaging in the practical world is not easy and should be incremental, with small but continuous improvements as used for most technological optimization problems (Baumann & Tillman, 2004). The eco-design strategies outlined in Table 18.3 may be formulated in optimal combinations. Some simple rules, such as reduce, reuse, and recycle (the three Rs) may be referred to as a first step: nine of the ten success stories of sustainable packaging reported by Sterling and Mohan (2008) are based on the reduce, reuse, and/or recycle attributes. General eco-design tools such as the MET matrix, POEMS, 10 golden rules, and the ecostrategy wheel, can also be mentioned (Baumann & Tillman, 2004) (Table 18.3 provides a summary of these tools). For, example, the ecostrategy wheel consists of eight suggestions: optimize function, reduce impact during use, reduce diversity of materials, choose the right materials, optimize life time, optimize production, optimize waste treatment, and optimize distribution. In applying these rules and guidelines, common sense is important. Many opportunities for change exist throughout the whole cycle of food processing, package design, distribution, logistics control, marketing, and consumer handling, and an accumulation of small changes could lead to substantial improvement and innovation.

The proper utilization of eco-design assessment methods or software such as PIQET^TM, TOP^TM and MERGE™, described above, will help to achieve standards and clear guidelines. LCA software packages such as Eco-IT^TM, Eco-Scan^TM, EPS^TM, Gabi^TM, SimaPro^TM, and Umberto^TM may be used and linked to an internal life cycle inventory (LCI) database, or to an external public database, in order to evaluate a certain package or to compare possible design options. Scorecard systems such as Wal-Mart's Sustainable Packaging Scorecard^TM may be applied to compare the alternative designs. Carbon footprint calculators available on websites can be used to obtain carbon footprint values.

18.3.1 Design and material innovators

Food and beverage package designers construct total packaging systems, from primary to tertiary packaging, to achieve the specific requirements demanded, such as protection, preservation, and convenient handling/distribution. Structure design and dimension changes can minimize total usage of packaging materials in the packaging life cycle and it is therefore important to connect design innovations with packaging material innovations, such as the develeopment of biodegradable, compostable, edible, or other active packaging materials.

Lewis (2008) suggested very practical guidelines for eco-design of food and beverage packaging, including strategies for eco-efficiency, design for recycling, design for composting, avoiding toxic substances, and environmental communication, which are summarized as part of Table 18.3. Therefore, the discovery of high-barrier materials to reduce material usage, materials with higher recycling rates, 100% compostable/edible materials, materials non-toxic to humans and also to the environment, and materials well suited to fit an existing environmental protection program, are required so that food packaging designers can achieve more sustainable food and beverage packaging.

Plastics have rapidly become ubiquitous in our everyday life and are used in all industries, contributing to the economic development and modernization of human life. Although plastic-based flexible packaging materials and containers are crucial in the food industry, their use in food packaging also sparks concerns for environmental pollution. Most plastics used for food packaging are semi-permeable and non-degradable providing limited shelf life for the packaged foods, and releasing various hydrocarbons when incinerated and land-filled, as well as emitting air pollutants when not completely combusted (Brown, 1993; Garcia et al., 1992; Guillet, 1973). Massive quantities of waste plastic materials, including bags, Styrofoam, and containers, are cited as the culprit of environmental pollution (Brown, 1993; Garcia et al., 1992; Guillet, 1973). By making plastics environmentally degradable by sunlight, soil microorganisms, or by the heat of landfill gas, the use of plastics would be safer and more versatile.

The use of degradable plastic materials for shopping bags and plastic containers is mandatory in some developed countries, including the US, Japan, Germany, and Italy (Narayan, 1994; Huang et al., 1990), as part of an effort to develop a new degradable polymer and commercialize degrad-able plastic products. Degradable plastics are divided into three types -biodegradable, bio-disintegrable, and photodegradable - based on their raw materials and the reaction mechanisms in their chemical composition (Albertsson et al., 1992; Bloembergen et al., 1994; Doane, 1992; Scott, 1990).

Biodegradable plastic packaging is manufactured from biopolymer materials such as polylactic acid (PLA), polyhydroxybutyrate (PHB), pullulan, and hyaluronic acid (HA), or from naturally derived substances such as alginate, cellulose, and chitin. These compounds of biological origin are combined with other polymer materials in the manufacturing process. However, biodegradable plastics are not seen as a complete replacement for plastics used in food packaging because they are weak in terms of tensile strength, water resistance and processing efficiency, as well as being costly (Bloembergen et al., 1994).

Bio-disintegrable plastics are made by integrating naturally degradable compounds such as cornstarch with synthetic polymers and various degradation accelerators to increase their degradability (Doane, 1992). Although bio-disintegrable plastics are not costly, they cannot be used for food packages due to their lower durability and strength, limiting their use to shopping and garbage bags.

Photodegradable plastics disintegrate when exposed to sunlight. Ultraviolet radiation disintegrates the polymer structure and eventually lowers the physical properties of the resin and polymer molecules, leading to further degradation. Adding transition metal catalysts, oxidation accelerators and photosensitive materials to the main fraction of the polymeric species accelerates the photodegradation and makes these plastics photo-degradable (Scott, 1990; Albertsson et al., 1992). Although the production of photodegradable plastics is cost effective, contemporary technology only allows the production of films. The problem with photodegradable plastics is that they remain non-degradable in landfills due to the lack of sunlight and are inextricably dependent upon the environment to degrade. Moreover, the use of photosensitive additives raises concerns over heavy metal toxicity (Albertsson et al., 1992). Recent innovations have tried to combine biodegradable, bio-disintegrable and photodegradable properties in a single plastic but so far it has not been possible to overcome the cost barrier for wide application and use.

18.3.2 Supply/distribution chain management

Food packaging design should be closely dependent on the food supply chain where many different scenarios can affect environmental impacts and sustainability parameters. Through a proper management of the products in the food supply chain, the sustainability of the food packaging can also be improved.

Theoretically, food shelf life can be extended by the use of less permeable packaging materials at a higher cost. Conventionally, it has been assumed that high gas and light barrier packages preserve food quality better and, thus, protect the product, also contributing to reducing the environmental impact of the total food packaging system. However, it must be noted that most high barrier plastic packaging materials consist of multi-layers of different sources, making it difficult to recycle the packaging waste (see Fig. 18.3). As a different approach, a food chain with a shorter shelf life and adequate quality control could be proposed, allowing materials consisting of a less protective single layer and thus imposing a lower environmental impact. Even though single OPP (oriented polypropylene) film cannot provide a shelf life as long as that of a multi-layer metallized PET/PE (polyethylene terephthalate/polyethylene), the desired quality can be met up to a period of 2 months (Pajin et al., 2006). Choosing the correct packaging conditions, providing an affordable food deterioration rate and shelf life can also meet the economic demands of sustainable packaging elements (see Fig. 18.4).

Shelf life optimization harmonized with supply chain management can save energy, materials and expenditure in inventory and temperature control throughout the whole distribution system. While the advocating of local food with low food mileage is not a universal solution for the environmental problems of the food system, supply chain optimization can be a useful way to save resources and energy.

One concept of food supply chain optimization proposes the in-situ study of the food loss incident and its relationship to the packaging structure and will evaluate the minimization of the environmental impact of the system (Roy et al., 2009). As shown in Fig. 18.4, too much emphasis placed on the food supply chain to reduce food loss (or over-extending the shelf life) increases the environmental impact, whilst poorly designed packaging or too short a shelf life will also increase the environmental burden. Reduction of food loss by proper means is a key element of lessening the environmental impact of integrated food chains (Davis & Sonesson, 2008) and, moreover, an optimized packaging and supply chain also helps economic competiveness (Fig. 18.4).

Fine tuned logistic control of a food and beverage supply chain is an essential factor in a successful sustainability strategy. Package reuse systems can only be successful with the successful establishment of refillable container logistics upstream and downstream (Parker, 1999). There must be a high return rate of the used containers in terms of distribution logistics and consumer participation. However, if the journey undertaken by the filled and emptied bottles is too long, their reuse does not give any advantage compared to one-way use.

Conventionally the principle of 'first-in, first-out' is practiced in food logistics management. However, time-temperature indicators or intelligent packaging devices advising food quality can also ensure the quality of delivered products. A stock management database including food quality change kinetics could be established for successful achievement of sustainability, as, for example, with a logistics management method that rotates chilled fish stock based on quality predictions or monitoring to reduce waste (Koutsoumanis et al., 2005).

The use of returnable and reusable secondary packaging like plastic crates or multi-use corrugated cases reduces energy and waste compared to single-use cardboard boxes (Bishop & Hanney, 2008); the large open spaces in returnable plastic crates have the potential for rapid cooling and homogeneous inside temperature profiles under well-controlled chilled storage conditions, which can contribute to quality retention.

Logistic design harmonized with sustainable packaging design can control the time taken for packaged foods to reach consumers with appropriate levels of freshness and quality. Consumers today appreciate that freshness, but also have a growing concern for environmental conservation. Effective and efficient design of food logistics including temperature management and shelf life control can contribute to reducing the environmental impact of food products and packaging.

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