Optimized Refrigeration Could Cut Global Food Waste by Half, Finds U-M Study

A new study by the University of Michigan, in collaboration with Clean Kilowatts, reveals that nearly half of global food waste, estimated at around 620 million metric tons, could be eliminated through fully refrigerated food supply chains. This reduction could also cut food waste-related greenhouse gas emissions by 41% globally. The findings, published in Environmental Research Letters, emphasize the significant environmental and economic benefits of improving cold-chain infrastructure.

Globally, about a third of the food produced each year goes to waste, while around 800 million people suffer from hunger, according to the U.N.'s Food and Agriculture Organization.

The study identifies Sub-Saharan Africa and South and Southeast Asia as regions with the highest potential for reducing both food losses and related emissions through enhanced cold-chain implementation. Specifically, South and Southeast Asia could see a 45% reduction in food losses and a 54% decrease in emissions, while Sub-Saharan Africa could achieve a 47% reduction in food losses and a 66% cut in emissions.

"I was surprised to find the scale of our opportunity for reducing food loss and waste globally," said study lead author Aaron Friedman-Heiman, a master's student at U-M's School for Environment and Sustainability and Ross School of Business. "Approximately half of the roughly 1.3 billion tons of food that goes to waste annually can be solved through food supply-chain optimization."

Co-author Shelie Miller, a professor at U-M's School for Environment and Sustainability and at the College of Engineering, contributed to the study, which focuses on food losses from post-harvest to retail stages, excluding on-farm and at-home losses. The research accounts for greenhouse gases emitted during food production but not those related to refrigeration or other supply-chain operations.

The study, funded partly by Carrier Global Corp., highlights that the greatest opportunity to reduce food losses in less industrialized economies lies in the supply chain between the farm and the consumer. In contrast, in North America and Europe, most food loss occurs at the household level, making cold chain improvements less impactful on total food losses.

The research underscores the significance of meat-related food losses due to their high greenhouse gas emissions, despite being lower in quantity compared to fruit and vegetable losses. Meat losses account for over 50% of food loss-related emissions, with optimized refrigeration potentially eliminating more than 43% of these emissions.

The study also compares the benefits of globalized, technologically advanced food-supply chains with localized "farm-to-table" systems. "Hyper-localized food systems resulted in lower food losses than optimized global, refrigerated supply chains," Friedman-Heiman said, highlighting the value of supporting local food chains.

Using data from the U.N. Food and Agriculture Organization, the researchers developed a food-loss estimation tool to assess the impact of improved cold-chain access on food loss and greenhouse gas emissions across seven food types in seven regions. The study estimates that inadequate cold-chain infrastructure could cause up to 620 million metric tons of global food loss annually, leading to 1.8 billion tons of carbon dioxide emissions, equivalent to 28% of U.S. annual greenhouse gas emissions.

The adaptable tool created by the researchers is intended for use by anyone in the food supply chain, including farmers, grocery retailers, government officials, and NGOs.

The study highlights that meat accounts for a disproportionate amount of food loss-related greenhouse gas emissions. Optimized refrigeration could significantly reduce these emissions, but actual savings depend on the efficiency of cold-chain technologies and the carbon intensity of local electrical grids.