Life Cycle Assessment (LCA) of Food Products and Production Systems

Doktorsavhandling, 1998

Life Cycle Assessment (LCA), which is a method for analysis and assessment of the environmental impact caused by product systems, and its application to food products and production systems have been studied. For foods, the complete product system includes: production of inputs to agriculture, agricultural production, industrial refining, storage and distribution, packaging, the household phase and waste management. The overall objectives were to learn more about the feasibility and limitations of LCAs of food systems and to generate information on the environmental impact of such systems. Case studies of tomato ketchup and white bread were carried out. Ketchup was chosen because its life cycle represents a rather common food-product system: it includes a harvest, a preservation process (seasonal production), storage, transportation and, finally, further processing into a consumer product. Bread was chosen because it is an important staple food. For ketchup, a screening LCA and, later, an analysis of options for environmental improvements were carried out. For bread, different scales of production and their potential environmental effects were compared; systems for home baking, a local bakery and two industrial bakeries with distribution areas of different sizes were studied. Energy use and emissions were quantified and the potential contributions to global warming, acidification, eutrophication and photo-oxidant formation were assessed. In the screening of ketchup, the impact categories of human toxicity and ecotoxicity were also included; for bread, land use for cultivation and the use of water for food processing were included. The great scarcity of environmental data was one of the major problems encountered when applying the LCA methodology to food systems. Hence, the data collection and modelling were time consuming and the uncertainties of the results were relatively large. Each individual LCA study contributes to the generation of new data as well as the identification of data gaps. Further research and development are required to improve both data bases and models so that the uncertainties can be reduced. Until high quality environmental data are accessible, there is a need for simplified methods which can be used as a compass to show the direction towards sustainability. Accordingly, the feasibility of combining the concept of sustainability and LCA for product development was examined and discussed. The main conclusion is that LCA is very valuable for incorporating environmental aspects in the evolution of more sustainable systems for production and consumption of foods. For ketchup it was found that the packaging and processing in food industries are significant in the total environmental impact made by ketchup. From the improvement analysis, it was concluded that, in particular, the contribution to acidification can be reduced significantly. For bread, it was concluded that the specific systems for home baking, the local bakery and the small industrial bakery show similar environmental performance. The large industrial bakery was found to require more energy and to contribute more to global warming, acidification, eutrophication and photo-oxidant formation. The combination of the concept of sustainability principles and the methodology of LCA was found to yield a simplified method well suited for screening analysis and product development aiming towards sustainability. The semi-quantitative approach eases the inclusion of information and aspects not usually included because they are difficult to quantify; for foods such information and aspects are often of major significance.