Most of the initially conducted LCA studies compared different packaging materials. For example, for milk, a large number of studies has been carried out comparing single-use cartons with disposable and refillable bottles of both glass and polycarbonate. An ecologically sound recycling and recovery of the packaging material strategy combines mechanical recycling with efficient feedstock recycling and energy techniques.
The analysis clearly showed that mechanical recycling of the high-grade film and bottle fractions, which only accounted for about 30% of the plastic packaging of households, has already reached its limits (Boudouropoulos and Arvanitoyannis, 1999, 2000). In the feedstock recycling and energy recovery sectors, the blast furnace process, thermolysis using the BASF process, monocombustion, for which pilot plants are only available abroad at present, and hydrogenation at the Kohle-Ol-Anlage are in the top group.
Consequently, classification into mechanical recycling, feedstock recycling and energy recovery techniques is merely process-orientated and does not constitute an ecological evaluation (Rob, 1996). Table 3.2 provides a synoptic presentation of the LCA studies carried out on foods and (food) packaging materials. Life cycle assessment (LCA), the systematic inventory and evaluation of environmental impacts of a product ‘from the cradle to the grave’, is an emerging tool.
Seafood products have hardly been studied from an LCA perspective. Ziegler et al. (2003) have studied the entire life cycle of frozen cod as an example of seafood, emphasizing the fishery-specific types of environmental impact. Thrane (2004) worked on the analysis of a wide range of Danish fish products, such as flatfish, also from a life cycle perspective. A finding common to both studies is that the fish harvesting stage of the production cycle typically accounts for 70–95% of the total impact regardless of the impact category considered. Hospido and Tyedmers (2005) studied thoroughly the fish harvesting stage.