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Life Cycle Assessment: Principles, Practice and Prospects
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therefore has cultural, social and economic consequences for existing agricultural and related
communities. An appropriate question might be: ‘we have land, water allocations and farmers
– what is the best thing to do?’ But LCA can realistically only contribute to environmental
dimensions of possible ‘answers’ to this question, in providing options for optimising the use
of these available ‘resources’. It is, however, a potentially powerful technique for application
beyond the practice-driven ‘optimisation’ question to the policy-driven questions of what to
do with particular limited resources such as land and water (and potentially, greenhouse gas
emissions, under a carbon trading regime).

9.4 Tail wagging the cow? LCA of milk production
and packaging
The dairy industry is significant in Australia, and the need to understand the life cycle impacts
through various stages and products of the industry led to a study sponsored by Dairy Aus-
tralia, with links to the International Dairy Federation and the United Nations Environment
Programme (UNEP) (Nicol 2005). The research was undertaken by Sven Lundie and Andrew
Feitz at the Centre for Water and Waste Technology (University of NSW) and Michael Jones at
the Centre for Food Technology (Queensland Department of Primary Industries). The scope
of the study is extensive, covering both a range of environmental impacts and the full life cycle,
including by-products, as well as post-farm processing, packaging and transport.
Particular focus was placed around water, energy and greenhouse impacts, particularly on
the split between on-farm and post-farm activities. The study was conceived partly out of
concern that the packaging of milk is a significant environmental problem. However, cor-
rectly, the LCA was scoped to include these impacts across the life cycle, rather than assuming
outcomes and focusing entirely on packaging.
The LCA results indicate that any pre-conceptions about life cycle impacts of dairy packag-
ing were best treated with caution. For example, on-farm water use was found to be far more
significant than that associated with packaging and manufacturing, with 99% of life cycle water
use being consumed on the farm, and only 1% in manufacturing and packaging (Nicol 2005).
Notably, differences were identified between chilled/fresh and aseptic/ambient packaging
options, in significant part as a result of the structure and configuration of the packaging and
processing industry surrounding these technologies. The few aseptic/ambient packaging plants
means that large transport distances are necessary and this leads to a relative rise in the envi-
ronmental burden attributable to the system. Hence, in the ‘market milk’ (fresh milk) option
analysed, energy use associated with packaging contributed 14% of the total, with 21% attrib-
utable to the farm, 14% to manufacturing, and 3% to retail transport. In the case of ultra high
temperature (UHT) milk, these proportions changed to 19% for packaging, 13% to the farm,
18% to manufacturing, and 19% for retail transport. This particular infrastructure arrange-
ment leads to a higher overall energy use for the UHT scenario compared to fresh milk, per
tonne of product. As expected, the energy footprint of yoghurt and cheese is significantly
higher per tonne of product than either milk scenario.
Unlike many LCA studies, the results for greenhouse gas emissions do not follow the
pattern identified for energy use. This is principally due to the methane emissions associated
with ruminants. As a result, in this study, some 52% of greenhouse gas emissions were found
to be attributable to the farm, compared to only 13% to 21% of energy use.
This reported study is only one of many conducted on dairy production worldwide, and there
is a high level of interest in the environmental impacts of dairy farming and products, reflected
in the level of LCA activity, including subsequent studies led by Dairy Australia (e.g. Feitz et al.
2007). The range of emissions and activities involved in the complete dairy production chain

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