Following an analysis of greenhouse gas emission at 536 dairy farms and 50 dairy processing plants, an inter-departmental team from the University of Arkansas identified a number of opportunities to reduce the environmental impact of the industry.
Regarding product packaging, the researchers advocated the use of thermoforming technology to manufacture more environmentally-friendly milk packaging.
“Emissions savings for packaging could come from improved bottle designs, resulting in reduced material use and upgrades to modern, energy-efficient formation equipment,” said a report produced by the researchers.
“...changing the bottle cap manufacturing process from injection-moulding to thermoforming may lower environmental burdens," the study concluded.
Thermoforming involves heating a plastic sheet and moulding it to a desired shape using pressurised air. The process avoids waste by recycling scrap plastic, and according to the study, equipment may be more energy-efficient than older injection-moulding technology.
Yogurt cups, egg cartons, take-away beverage cups, and fresh food containers are already manufactured using thermoforming methods.
Carbon emissions twice the volume of milk
The research is welcome at a time when, according to the study, 2.05 kilograms (kg) of carbon dioxide are produced per kg of fluid milk consumed.
The findings may help the US Department of Agriculture (USDA) and the Innovation Center for US Dairy to reduce greenhouse gas emissions by 25% by 2020 – an agreement renewed in April by US Secretary of Agriculture, Tom Vilsack.
Previous efforts to reduce the carbon footprint of the dairy industry have focused on recycling methane produced by cows (enteric methane).
Although the industry's largest greenhouse gases contributions are produced at farm level – in “feed production, enteric methane and manure management” – the researchers hope that the comprehensive nature of the study will open other avenues to carbon reduction among dairy manufacturers.
“Our analysis provides a documented baseline for their improvement efforts. It is a source for understanding the factors that influence environmental impact,” said lead researcher, Greg Thoma, a professor of chemical engineering.
Source: The International Dairy Journal 31 (2013) S3-S14;
"Greenhouse gas emissions from milk production and consumption in the United States: A cradle-to-grave life cycle assessment circa 2008"
Authors: Greg Thoma, Jennie Popp, Darin Nutter, David Shonnard, Richard Ulrich, Marty Matlock, Dae Soo Kim, Zara Neiderman, Nathan Kemper, Cashion East, Felix Adom.