New research has shown that eggs have the lowest carbon footprint of all the main protein foods.
The research, which was commissioned by the Australian Egg Corporation (AECL), comes at a time when environmental impact is an increasingly important issue for major retailers. Food producers are being told to think more carefully about the environmental impact of their businesses in order to meet the future demands of those who will buy their produce. This new research work funded by AECL shows that egg producers already have a head start in addressing environmental concerns.
AECL managing director James Kellaway said the research was another good reason for consumers to include eggs as part of their daily diet. ’This study has highlighted some surprising results, including suggesting that the humble egg is now the highest quality protein food with the lowest emissions," he said, although he conceded that there was still room for egg producers to improve their environmental performance further. "The research highlighted that there is still scope for refinements to current practices in egg production to allow further reductions in emissions. AECL wishes to conduct further studies on this important topic,’ he said.
The research project was conducted by Steve Wiedemann and Eugene McGahan on three Australian farms over a period of one year. Together, the farms had more than one million birds housed in both cage and free range units. To undertake their work, the researchers used life cycle assessment - a method that involves analysing the whole production process - including items like the electricity used on the egg production units, energy used to manufacture feed and diesel used in tractors used in growing wheat. The method even takes into account such things as the production of the diesel, itself. "It is quite a comprehensive tool," said Steve Wiedemann. He said that during this particular project the research team had been interested in energy and water use, as well as greenhouse gas emissions from egg production.
The researchers were able to compare the environmental performance of cage birds with that of free range hens and concluded that the cage birds produced a lower carbon footprint than free range egg birds - something that has been suggested previously by environmental scientists. The research team said that the larger carbon footprint of free range birds was due to the fact that they used more feed per kilogram of eggs compared with cage birds. The Australian research showed that greenhouse gas emissions from cage egg production amounted to 1.3kg of carbon dioxide equivalence, including methane and nitrous oxide, per kg of eggs. The figure for free range eggs was 1.6kg.
Researchers also found that Australian egg production had a lower carbon footprint than several European egg studies. This was mainly due to more efficient grain production in Australia. They said the largest carbon impact in the supply chain came from feed grain production, then manure management and energy use at the layer farm.
James Kellaway said, "With greenhouse gas emissions front of mind for many, this research provides consumers with the information they need to help reduce their carbon footprints when buying foods.’
The research team published its findings in a report entitled ’Environmental assessment of an egg production supply chain using life cycle assessment.’
The team concluded that Australian egg production was a "highly efficient form of protein production with respect to the environmental impacts and resource use issues addressed in this study." It said the relative environmental efficiency of egg production in the study arose from the high performance of modern Australian egg production coupled with the low input nature of Australian grain production. Australian grain was produced in conditions that did not favour nitrous oxide emissions, and this resulted in low greenhouse gas and energy use for Australian eggs, both in cage and free range systems.
Steve Wiedemann said the results of the research were good news for egg producers. "It’s good to show that Australian egg production is highly efficient from a resource and environmental point of view. I think we can all agree that we are going to need to produce more food from less. There will be less resources to go around and a world demanding more food. It’s good to know that eggs are right up there in terms of efficiency. If you compare some of the numbers with other animal production systems, taking into account there are quite a few differences, eggs are very efficient at turning grain into a protein product for human consumption."
He said there was likely to be more pressure for farmers to reduce greenhouse gases. "Whether you like that or not it’s good to know that egg production is pretty efficient already and there are also some opportunities to improve that efficiency as well."
The research team suggested that measures to reduce feed use would be highly beneficial to the Australian egg industry, although considering the high degree of feed efficiency achieved to date, it said that substantial further gains were expected to be more difficult to achieve. Reducing farm electricity use could lower energy use, lower GHG and lower costs provided production levels could be maintained, said the report.
"Energy use and greenhouse gas are pretty closely linked to productivity," said Steve Wiedemann. "As the industry improves productivity - particularly things like FCR (feed conversion ratio) - that will drive down emissions over time. For example a 0.05 improvement in FCR would reduce greenhouse gas emissions by a couple of per cent. That’s not huge but I guess we have to take into account the fact that the industry is already fairly efficient and it shows a slow improvement over time."
If producers could reduce farm energy use at the same time as maintaining production, that would be another improvement, he said. There was also the possibility to generate energy from manure in the future, and the industry could look at the use of different feed formulations to reduce greenhouse gas emissions.
The researchers made a series of recommendations for further study. They said more work was needed on Australian feed grain systems and a broader spectrum of egg producers from other production regions was required to produce results that could be considered representative of the whole Australian industry. Research should be carried out into mass flows, excretion and emission rates from modern cage and free range production facilities. And they said collection of energy and water benchmarking data from across a greater cross section of the industry was required. This data would provide a robust basis for targeting industry improvement and could be integrated into future studies.
