## 2 Challenges in Food Supply Chains Related to Packaging Characteristics
### Food Waste and the Meaning of Packaging  
Food wastage and loss describe a major concern in the food supply chain that takes all of the involved stakeholders into consideration [58]. There is an increasing concern about the amount of food waste in Europe as wasted food has a significant impact on the use of natural resources and the environment [59]. The United Nations set a target of halving the actual amount of global food waste per capita at retail and consumer levels and reducing food losses along production and food supply chains as part of their sustainable development goals for 2030 (goal 12.3 of the UN General Assembly) [59]. Differentiating between avoidable (edible) food waste and unavoidable (non-edible) food waste, proper waste management, and recycling strategies is required to reduce unavoidable food waste. Various chemical and biological processes can be used to convert food waste into bio-commodity chemicals and bio-energy [60]. Packaging prevents avoidable food waste and has the potential to further decrease it [42]. According to a study of [PERSON] et al., the shelf life of poultry under aerobe packaging conditions at 4 \({}^{\circ}\)C accounts for 98.6 h [61]. At 4 \({}^{\circ}\)C, the shelf life of poultry packed under modified atmosphere packaging (70% oxygen (O\({}_{2}\))/30% carbon dioxide (CO\({}_{2}\))) is prolonged to 228 h [62]. The kind of packaging has a high impact on the shelf life of poultry and can more than double it. [PERSON] et al. focused on food waste generated in the EU for the major food groups: sugar beets, oil crops, potatoes, vegetables, fruit, cereals, meat, fish, dairy, and eggs. The food waste generated at each stage of the food supply chain was quantified. In total around 638 mega tons (Mt) primary foods result in approximately 129 Mt of food waste generated along the food supply chain. Fruit and vegetables were the food groups presenting the highest amount of food waste overall, with similar amounts generated at the primary production and consumption stages [63]. Products of food categories with a relatively short shelf life, like fresh meat, tend to be the most wasteful products [64; 65]. The amount of wasted food means that not only the products themselves are lost but also a high amount of primary resources of fuel, land, and water, including resources needed for breeding and fattening of animals, for cultivation of plants, and raw materials for processing and packaging during production as well as along the entire supply chain [65; 66]. Therefore, for a packaging system, it is important to find a balance between the environmental impact of the package itself, on the one hand, and the impact originating from the potential loss of the packaged product, on the other [66; 67]. Considering the environmental impact, this is much higher for producing the food itself than the (multi-layer) plastic packaging. Therefore, if food waste occurs, the negative overall environmental impact rises with every step in the supply chain due to more used resources [8; 66; 68]. An analysis of the food supply chain and the points where food waste is generated showed that reducing packaging is important, but it must still fulfil its duty of protection as the main criteria for sustainability. Otherwise, the supply chain overall will be less sustainable [24; 68; 69]. [PERSON] reported that the production of starch plastic granules requires 25-75% less energy, and GHG emissions are reduced about 20-80% compared to poly(ethylene) (PE) [70]. [PERSON] et al. reviewed the environmental impacts of bio-based materials in a meta-analysis of LCA data. Therefore, one metric ton (t) of bio-based materials saves \(55\pm 34\) gigajoules (GJ) of primary energy and \(3\pm 1\) t carbon dioxide equivalents of GHG emissions relative to conventional materials [31]. [PERSON] et al. assessed the environmental impact of single-layer and multi-layer conventional packaging.