Better climate information reduces waste in the school canteen. This is a clear finding of the Food Waste Experiment, a mass experiment in which around 700 pupils from 27 schools in Sweden helped researchers to investigate whether “nudging” can reduce food waste. The Experiment was run as part of the science festival ForskarFredag, the Swedish European Researchers’ Night.
“The pupils that participated have proven that it is possible to both measure and reduce food waste with the help of a mobile app. In order to be able to make informed choices, pupils, in fact all of us, need the right information at the right time. This is essential if we want to create a more sustainable society,” said Roberto Rufo Gonzalez, a researcher at the company Consupedia that runs the world’s largest sustainability database about food.
Our food is responsible for over a third of human-caused climate emissions. At the same time, almost one third of food produced globally is thrown away. Reducing our food waste can therefore really help tackle climate change. One sub-goal of the UN’s Sustainable Development Goals is to halve global food waste (sub-goal 12.3, under goal 12: Responsible consumption and production).
Measurements led to reduced waste
In the Food Waste Experiment, pupils first helped to “train” an artificial intelligence in a mobile app to recognise different dishes served in the school canteen. Then they used the app to access information about the climate footprint of the various dishes on the lunch menu, and to measure how much food they threw away. The results, which have now been published, show that food waste decreased by about 16 percent during the two weeks that the Food Waste Experiment was running. The average amount of food thrown away per dish during the entire period was 19.85 grams, which is 27 percent less than the 27 grams reported in a survey of plate food waste in Swedish schools undertaken in 2019 by the Swedish National Food Agency.
“A few grams per meal may not sound like much, but in Sweden around 1.3 million school meals are served every day. This means that even small changes can lead to huge improvements,” commented Roberto Rufo Gonzalez.
Together we can create virtuous circles
The meals recorded in the Food Waste Experiment took an average of 10 minutes and 24 seconds for the pupils to eat. Pupils in the higher stage of compulsory education (högstadiet, 13-15 years) throw away more food than middle stage (mellanstadiet, 10-12 years) or upper secondary (gymnasiet 16-18 years) pupils. Pupils in the higher stage of compulsory education also enjoyed the food less and felt less full than the middle stage and upper secondary school pupils that participated.
“Overall, we can see a connection between more time, tasty food, fuller students and less waste. Everyone involved in the school food chain in Sweden has an opportunity to contribute to creating virtuous circles and reducing waste,” said Roberto Rufo Gonzalez.
Citizen science in action
The Food Waste Experiment, which took place during November 2020, is an example of citizen science, where researchers enlist the help of the public to investigate issues that they don’t have the capacity to research on their own. VA has been coordinating an annual mass experiment as part of European Researchers’ Night activities in Sweden, known as ForskarFredag, since 2009.
“Our mass experiments are an exciting way for pupils to participate in real research together with researchers. Often they are aimed at creating new and important knowledge about societal challenges that need to be solved. This year’s mass experiment, the Housing Experiment, is investigating the accessibility of Swedish housing for senior citizens and those with disabilities,” explained Julia Brink, a Project Manager at VA and the national coordinator of ForskarFredag.
The Food Waste Experiment is a collaboration between the KTH Royal Institute of Technology, Dalarna University, the company Consupedia and the non-profit organisation VA (Public & Science). The project is funded by the Swedish Energy Agency and Consupedia.