The LCA: Goal & Scope
The LCA is what is known as a ‘cradle to gate’ LCA. This means that it includes all the processes and emissions throughout the chain, from the cultivation of the raw materials needed to produce the cattle feed to the dairy factory. The data for the dairy farm come from the literature and national databases. The data for the dairy factory were provided by FrieslandCampina. Six environmental indicators were analysed: greenhouse gas emissions, acidification, nitrogen fertilisation, phosphate fertilisation, land use and fossil energy use. The goal of the LCA was not to compare the environmental impact of semi-skimmed milk with that of semi-matured Gouda cheese. The function of these two products (such as nutritional value) differs on too many points for it to be possible to compare their environmental impact one on one per unit weight.
The impact of semi-skimmed milk
The emission of greenhouse gases from the production of semi-skimmed milk is between 0.91 and 1.44 kg CO2-eq/kg, with an average of 1.12 kg CO2-eq/kg. Rumen fermentation in cattle makes up about 35% of the total greenhouse gas emissions. The manure stored in the livestock shed, dropped in the field or spread on the land makes a considerable contribution to the total greenhouse gas emissions of semi-skimmed milk. The emissions on the farm are the most significant element in almost all the environmental impacts, but not for fossil fuel use. Fossil fuel use for semi-skimmed milk is between 0.12 and 0.18 kg oil eq/kg, with an average of 0.14 kg oil eq/kg. Besides the on-farm use of fossil fuels, important contributions to fossil energy use are made by the retail sector, the dairy factory, packaging and consumers. The land use of semi-skimmed milk is between 0.71 and 1.2 m2a/kg, with an average of 0.91 m2a/kg semi-skimmed milk. The land used for the production of animal feed is located in the following countries, in order of decreasing area: the Netherlands, Brazil, Germany, Argentina and France.
Figure 1: Location of land used for the cultivation of ingredients used in compound feed and protein-rich feed or by-products in m2a for 1 kg milk on the farm.
The impact of semi-matured Gouda cheese
The emission of greenhouse gases from the production of semi-matured Gouda cheese is between 6.9 and 11.8 kg CO2-eq/kg, with an average of 8.67 kg CO2-eq/kg. Emissions from the farm, the dairy factory and point of sale (cooling) make a major contribution to total greenhouse gas emissions. These phases in the life cycle also make an important contribution to fossil energy use. Fossil energy use for the production of cheese lies between 0.68 and 1.13 kg oil eq/kg, with an average of 0.84 kg oil eq/kg. Land use, eutrophication and acidification result mainly from activities and emissions on the farm. Land use for the production of semi-matured Gouda cheese is between 4.88 and 8.89 m2a/kg, with an average of van 6.27 m2a/kg.
The results of the LCA are influenced not only by the ranges in the data used, but also by a number of methodological choices. The impact of changing land use (direct land use change – dLUC) is not included in the baseline scenarios. Depending on the method used to calculate this impact, it results in an increase in emissions of greenhouse gases for semi-skimmed milk of 7–21% and for semi-matured Gouda cheese of 8–24%. The environmental impact was allocated to on-farm co-products (milk, meat, calves) using the IDF allocation method. This method allocates impacts according to the amount of energy a cow needs to produce milk, meat and a calf. Another much used allocation method is economic allocation. If economic allocation is used for on-farm impacts, 92.2% of the emissions are allocated to the milk on the farm, compared with 86.0% under the IDF method.