|Milk production (mælkeproduktion)|
The present data
refer to milk production in Århus Dairy and Hobro Dairy
in 2001 to 2002. The
main production processes
at the two dairies are
following: 1) milk from
dairy farms is received, 2) the milk is centrifuged and seperated into cream and skim-milk
3) the two
fractions are mixed in different ratios depending on desired quality of milk (standardisation)
4) the standardised milk is low pasteurized (heat treatment 72oC in 15 seconds)
and eventually homogenised 5) the milk is paked and stored cool until
distribution to consumers. Some cream is converted into
butter and buttermilk
and some skimmed milk is converted into
evaporation in subsequent processes.
Wastewater generated during the process is diverted directly to municipal wastewater treatment. The two dairies are characterised by a high
degree of specialisation in milk production for the consumer market (cream,
fullmilk, low-fat milk and skimmed milk). All production processes are
automatic and modern.
Data are derived from Århus and Hobro Dairies' records (Green Accounts 2001/2002). Avarage inputs and outputs per produced unit of milk have been calculated ignoring minor contributions from other products. All products are subject to the same main processes and no differences between products have been considered regarding energy consumption and emissions to water. However, fat-content vary between milk products (see table below) and differences in milk consumption and cream production have been taken into account assuming 4.3% fat content of the fresh cow milk.
Homogenisation requires about 4% of total electricity for milkproduction and diferences between homogenised and non-homogeniosed milk with respect to electricity consumption have been ignored.
Production processes from receival of fresh cow milk to storage of the final product before distribution as well as administration has been included. Packaging, cleaning agents and chemicals are not considered.
technology is used in other dairies in Arla. Arla is a major supplier of milk
to the danish market and the present data provides a reasonable representation
of milk production in Denmark.
Data have been compared with data obtained by Eide (2002) in terms of contributions to environmental impacts. Data on contributions to global warming and photochemical smog formation are at the same level as observed for small dairies whereas results differ quite much for larger dairies. The dairy analyzed here is quite large and the differences can probably be explained by different heat and electricity scenarios but maybe also different production principles.
Eide MH (2002). Lifecycle assessment (LCA) of industrial milk production. International Journal of Lifecycle assessment. 7 (1) 1-12.
Data URL: http://www.lcafood.dk/processes/industry/milkproduction.html