Environmental impact of Danish pork at slaughterhouse gate – a life cycle assessment following biological and technological changes over a 10-year period

• DOI: 10.1016/j.livsci.2021.104622
• Publication Date: 2021-07-25T05:22:21Z
• Authors: Teodora Dorca-Preda; Lisbeth Mogensen; Troels Kristensen; Marie Trydeman Kn...
• Keywords: Danish

Abstract Pork is one of the most consumed types of meat globally and it contributes considerably to environmental impact. The aim of this study was to investigate the development of the environmental impact of Danish pork between 2005 and 2016 in relation to biological and technological changes that have occurred at the primary production and slaughterhouse level at that time. A life cycle assessment approach from cradle to slaughterhouse gate was used, where Climate Change (CC), Eutrophication Potential (EP), Acidification Potential (AP), Abiotic Depletion (fossil fuels) (AD), Land Occupation (LO), and Biodiversity Damage (BD) were assessed and expressed by three functional units (live weight, carcass weight and ‘meat’ for human consumption). A decrease was found in the environmental impact of Danish pork per kg ‘meat’ from 2005 to 2016 for all environmental categories, especially for CC (-31%), EP (-26%), and AD (-45%). This decrease was the result of several biological and technological changes that had occurred in the chain. At the primary production level, an increased herd productivity was documented: the number of pigs produced per sow per year increased (total live weight gain from offspring per sow per year was 3348 kg in 2016 compared to 2422 kg in 2005) and the feed use per kg live weight was reduced. These changes led to lower N excretion rates, which together with improved housing and manure handling strategies contributed to reducing the environmental impact of pork. At the feed production level, several technological changes decreased the impact. Firstly, reducing the N application rates for cereals and rapeseed led to reduced N emissions. Secondly, the use of new technologies for producing N fertilizers reduced the CC impact per kg N fertilizer. Finally, increasing the share of wind-based electricity in the Danish electricity mix caused decreases in the CC, EP, and AD impacts per kWh. At the slaughterhouse level, the increased utilization of the proportion of pig parts for human consumption reduced the total impact in the chain by 5%. Thus, it was identified as an important improvement option, with environmental and economic benefits. The improved utilization of by-products contributed to a reduction of more than 50% in the impact from the slaughterhouse. In terms of methodological choices, accounting for soil C changes, direct and indirect Land Use Change increased the CC impact in both years, but decreases were observed in 2016 compared to 2005. The need to include more by-products in pig feed rations was discussed in relation to LO and BD.