University of Birmingham

New research from an international team of scientists has shown that raising the temperature of frozen food by just 3°C could safely reduce food loss and cut carbon emissions by 17.7 million metric tonnes of carbon dioxide a year.

Published today (Wednesday 29^th Nov) in a new report called Three Degrees of Change, the research suggests that frozen food temperatures could be changed from -18°C to -15°C to save the equivalent carbon dioxide emissions of 3.8 million cars per year.

The research was led by the University of Birmingham, the Paris-based International Institute of Refrigeration, and London South Bank University, among others.

The findings are timely as we struggle to manage food loss due to a lack of cooling in agri-food systems. Toby Peters, Professor of Cold Economy at the University of Birmingham, and Heriot-Watt University, who led the research and report said: “Globally, 12% of food produced annually for human consumption is lost due to a lack of proper temperature management. On top of this, an increasing global population raises the demand for food, while the rapidly warming planet will reduce food production. It is of the utmost importance that we find ways to combat food loss to achieve global equitable food security. Freezing food is one such method, but we need to achieve this as energy efficiently and sustainably as possible.”

Food freezing extends product shelf life safely for months and allows people to plan when to consume it. Research has demonstrated that frozen foods result in 47% less household food waste than fresh food categories. In total food that is lost and wasted accounts for 38% of total energy usage in the global food system. By freezing food, this loss can be reduced while there could be a shift to more environmentally friendly transportation methods, such as by sea rather than air. For example, shipping of frozen salmon from Norway to Shanghai reduces the carbon footprint against air freight.

Dr Leyla Sayin, Deputy Director, Centre for Sustainable Cooling and Cooling Specialist Advisor to the Department for Energy Security and Net Zero, said: “Increasing the temperature of frozen food by 3°C would make freezing food far less environmentally damaging. The standard temperature of -18°C was decided 93 years ago and has not changed since, so we have an inbuilt process of ‘over-freezing’ food. It is perfectly safe to freeze food at a higher temperature of -15°C and it would make freezing food at the point of harvest easier in hotter climates and to maintain during transportation.

“In the UK approximately 50% of food is imported from 160 countries, so a shift to more freezing at a higher temperature would have a huge impact, and not just at home. Apply this to the rest of the world and we are looking at a full transformation of the global food and cold chain.”

The research and report were supported by DP World, a global logistics firm and principal partner in COP28, which has set up an industry-wide coalition to build on the work and explore the feasibility of this change, named Join the Move to -15°C.

Maha AlQattan, Group Chief Sustainability Officer at DP World, said: “Frozen food standards have not been updated in almost a century. They are long overdue for revision.

“With this research and with our newly formed coalition, we aim to support collaboration across the industry to find viable ways to achieve the sector’s shared net-zero ambition by 2050.

“The Move to -15°C will bring the industry together to explore new, greener standards to help decarbonise the sector on a global scale. Through this research, we can see how we can deploy accessible storage technologies in all markets to freeze food at sustainable temperatures while reducing food scarcity for vulnerable and developed communities.”