System expansion and allocation in life cycle assessment of milk and beef production
Background, Goal and Scope
System expansion is a method used to avoid co-product allocation. Up to this point in time it has seldom been used in LCA studies of food products, although food production systems often are characterised by closely interlinked sub-systems. One of the most important allocation problems that occurs in LCAs of agricultural products is the question of how to handle the co-product beef from milk production since almost half of the beef production in the EU is derived from co-products from the dairy sector. The purpose of this paper is to compare different methods of handling co-products when dividing the environmental burden of the milk production system between milk and the co-products meat and surplus calves.
This article presents results from an LCA of organic milk production in which different methods of handling the co-products are examined. The comparison of different methods of co-product handling is based on a Swedish LCA case study of milk production where economic allocation between milk and meat was initially used. Allocation of the co-products meat and surplus calves was avoided by expanding the milk system. LCA data were collected from another case study where the alternative way of producing meat was analysed, i.e. using a beef cow that produces one calf per annum to be raised for one and a half year. The LCA of beef production was included in the milk system. A discussion is conducted focussing on the importance of modelling and analysing milk and beef production in an integrated way when foreseeing and planning the environmental consequences of manipulating milk and beef production systems.
This study shows that economic allocation between milk and beef favours the product beef. When system expansion is performed, the environmental benefits of milk production due to its co-products of surplus calves and meat become obvious. This is especially connected to the impact categories that describe the potential environmental burden of biogenic emissions such as methane and ammonia and nitrogen losses due to land use and its fertilising. The reason for this is that beef production in combination with milk can be carried out with fewer animals than in sole beef production systems.
Conclusion, Recommendation and Perspective
Milk and beef production systems are closely connected. Changes in milk production systems will cause alterations in beef production systems. It is concluded that in prospective LCA studies, system expansion should be performed to obtain adequate information of the environmental consequences of manipulating production systems that are interlinked to each other.
KeywordsAllocation beef production life cycle assessment (LCA) methane-emissions milk production organic agriculture system expansion
Unable to display preview. Download preview PDF.
- EC (1999a): The CAP reform: Milk and milk products. European Commission Directorate-Generale for Agriculture. KF-29-00-828-EN-CGoogle Scholar
- EC (1999b): The CAP reform: The beef and veal sector. European Commission Directorate-Generale for Agriculture. KF-29-00-852-EN-CGoogle Scholar
- ISO (1998): Environmental management-Life cycle assessment-Goal and scope definition and inventory analysis. ISO 14041:1998 (E). International Organisation for Standardisation, Geneva, SwitzerlandGoogle Scholar
- JBV (2001): Organic agriculture and food products-Plan of Action 2005 (Ekologiska jordbruksprodukter och livsmedel-Aktionsplan 2005. Jordbruksverket rapport 2001: 11, Jönköping, Sweden (in Swedish)Google Scholar
- Swedish Dairy Association (2001): Life Cycle Assessment of consumer milk. Livscykelanalys av konsumtionsmjölk. Svensk Mjölk, Stockholm, Sweden (in Swedish).Google Scholar
- Cederberg C, Darelius K (2000): Life cycle assessment of beef-A study of different production forms. (LCA av nötkött-en studie av olika produktionsformer. Naturresursforum, Landstinget Halland, Sweden, www.lthalland.se/nrf (in Swedish)Google Scholar
- IPCC(1995): In: Houghton, editor. Climate change 1995. Cambridge (UK): Cambridge University Press (published for IPCC)Google Scholar
- Lindfors L-G, Christiansen K, Hoffman L, Virtanen Y, Juntilla V, Hanssen O-J, Rönning A, Ekwall T, Finnveden G (1995): Nordic guidelines on life-cycle assessment. Nord 1995: 20. The Nordic Council. Copenhagen, DenmarkGoogle Scholar
- SCB (2001): Environmental account for the Swedish agriculture 2000 (Miljöredovisning för svenskt jordbruk 2000). The federation of Swedish Farmers, 105 33 Stockholm, Sweden (in Swedish)Google Scholar
- Swedish Dairy Association (2001): Dairy Statistics (Mejeristatistik). Svensk Mjölk, 105 46 Stockholm, Sweden (in Swedish)Google Scholar
- Swedish Dairy Association (2000): Milk and the Environment. Svensk Mjölk, 105 46 Stockholm, SwedenGoogle Scholar
- Bertilsson J, Emanuelson M, Salomonssson M (2001): Can dairy cows be fed on regional fodder exclusively? (Kan man utfodra korna med enbart närproducerat foder). In: Proceedings from the Swedish Dairy Association’s Animal Healdi and Feeding Conference, Linköping 21-23 August 2001, p 61-66 (in Swedish)Google Scholar