Each year, about a third of the food produced globally is wasted, while around 800 million people go hungry, according to the United Nations’ Food and Agriculture Organization (FAO).

A recent study from the University of Michigan finds that nearly half of this food waste—around 620 million metric tons—could be reduced with fully refrigerated food supply chains, or “cold chains,” worldwide. These cold chains could also cut food waste-related greenhouse gas emissions by 41% globally.

Better infrastructure

The study shows that Sub-Saharan Africa, South Asia, and Southeast Asia have the most to gain from better cold-chain infrastructure. In South and Southeast Asia, optimized refrigeration could reduce food losses by 45% and emissions by 54%. In Sub-Saharan Africa, food losses could drop by 47% and emissions by 66%.

Interestingly, the study also finds that localized “farm-to-table” food supply chains can save as much food as optimized cold chains.

“We were surprised by the scale of our opportunity to reduce food loss and waste globally,” the researchers said. They estimate that about half of the 1.3 billion tons of annual food waste could be solved through better supply-chain management.

A major cause

Food losses account for about 8% of human-caused greenhouse gas emissions. This research focuses on food losses from post-harvest to retail, not on-farm or household waste.

The study includes emissions from food production but not from refrigeration or other supply-chain operations, nor does it include emissions from food waste in landfills.

Key findings of the study include:

• In less industrialized economies, the biggest opportunity to improve food losses is in the supply chain between the farm and the consumer. In North America, Europe, and other industrialized regions, most food loss happens at the household level, making cold chain improvements less impactful overall.
• The study reinforces the importance of addressing meat-related food losses. While fruit and vegetable losses are higher by weight, meat losses produce more emissions due to the high greenhouse gas intensity of meat production.
• Unlike previous studies, this research compares globalized, advanced food-supply chains with localized “farm-to-table” systems. It finds that localized systems result in lower food losses than optimized global, refrigerated supply chains.

To conduct the study, the researchers developed a tool to estimate food loss and its greenhouse gas emissions for seven food types in seven regions, using data from the FAO and other sources.

Food loss

By modeling food losses at each stage of the supply chain, the study shows where cold chains can be optimized to reduce food losses and emissions. It estimates that poor cold-chain infrastructure could cause up to 620 million metric tons of global food loss annually, resulting in 1.8 billion tons of carbon dioxide equivalents—28% of U.S. annual greenhouse gas emissions.

The researchers suggest that their tool will be useful for farmers, grocery retailers, government officials, and NGOs involved in the food supply chain.

“Although cold chain infrastructure is rapidly increasing worldwide, optimized cold chains will develop at different rates and in different ways across the globe,” the authors say. They warn that while better refrigeration should reduce food loss and emissions, there are important trade-offs depending on food type and region.

Investment decisions should be prioritized to achieve the best outcomes. For example, NGOs focused on ending hunger might prioritize cold-chain upgrades that offer the biggest reductions in food loss. Those prioritizing climate action might focus on reducing meat losses, which have a disproportionate impact on greenhouse gas emissions.

The study found that meat accounts for over 50% of food loss-related emissions despite being less than 10% of global food losses by weight. Optimized refrigeration of meat could cut more than 43% of emissions from meat loss.

However, the researchers note that the actual amount of greenhouse gas savings will depend on the efficiency of cold-chain technologies and the carbon intensity of local electrical grids, since refrigeration-related emissions can be significant.