In a multi-country collaboration, the Strength2Food research group conducted a nutritional and plate waste study on food procurement in 10 primary schools in Europe. Mary Brennan, a food consumer researcher in the University of Edinburgh Business School, and colleagues from 14 organizations and universities in Croatia, Greece, Italy, Serbia and the United Kingdom, sought to highlight nutritional outcomes of different procurement models in primary schools and the subsequent plate waste trends that influence the sustainability of these models. Refusal and wastage rates result in a nutritional intake lower than recommended values, while also driving unnecessary food waste.

Vegetable food waste collected during one lunch at a participating primary school.

About a third of all food produced is lost or wasted globally, according to the World Food Programme. That amounts to 1.3 billion tons wasted per year, jeopardising the UN’s Sustainable Development Goal 2: Zero Hunger. Goal 2 strives for eliminating hunger in the world by 2030. In addition to this being a food security issue, food waste has significant climate impacts. When food is wasted, so is the energy and water it took to grow, harvest, transport and package it. If food is discarded into a landfill, its rot produces methane, a greenhouse gas more potent than carbon dioxide. Our World in Data estimates that 6% of greenhouse gas emissions come from food losses and waste.

For primary-school children specifically, plate waste can have detrimental effects on their growth and development. According to the researchers, nutrition of young children is one of the most significant public health issues facing almost every country in the world. A child’s nutritional intake can be influenced by food standards and nutritional guidelines, food procurement policies, the school food facilities, and the processes and practices for delivering school meals.

While the research group looked broadly at contributing factors influencing food waste and nutritional and carbon loss, the offering of a school meal is something many kids rely on. For kids experiencing food insecurity, the one certainty they have is that every day at school, they get food they know they enjoy, Brennan reflected.

“Some of those kids just wanted sausage, beans and chips every day. And my attitude is that I’m not sure as a liberal middle class privileged elite that I should be saying they can’t have sausage, beans and chips every day if that’s the only hot meal they’re getting. I think we might need a bit more nuance. We estimate that there might be as high as 20% to 25% of children now in the UK who get their only hot meal at school. We may need to be a bit less precious about what we’re giving them so that we can ensure that they really enjoy it and that they consume all of this,” Brennan said.

A cafeteria of a participating primary school where children eat their school lunch.

Strength2Food methods

To assess differences between procurement models, the researchers conducted comparative case studies in each country with two schools representing different procurement models, local sourcing (LOC) versus low cost (LOW). LOC procurement was considered the more sustainable method out of the two. The Italian case study varied slightly in that it compared local organic (LOC-ORG) and organic (ORG) procurement, with LOC-ORG being the more sustainable option. A comparison was achieved with a food composition analysis (FCA), whereby the researchers calculated nutritive values of menus, collected and evaluated plate waste at the selected schools, and assessed nutritional and financial losses and carbon burden attributed to the plate waste.

The daily menu for each of the 10 schools was collected for a period of 5 consecutive school days during 2 seasons (autumn/winter and spring/summer) in the 2017/2018 school year. This amounted to a total of two collection weeks at each school. The nutritive values of the school lunches were calculated using national composition tables for each country and broken into values for total energy, macronutrients, and selected micronutrients. For foods not included in the national food composition database, values were obtained from food labels. Food waste was collected and separated into seven food categories: starchy food, bread, protein-based dishes, vegetables, fruits, desserts, and other. The waste was subsequently weighed. The percentage of food waste for every food category was computed as the ration between the total edible plate waste and the total amount served to children. By subtracting the energy and nutrient content of the plate waste per child, an estimation of the actual energy and nutrient intakes was provided.

Locations of 10 primary schools included in the Strength2Food study.

Nutritional impact

Large variations were found in the nutritional composition of the school menus across countries, as well as in plate waste. The quantities and compositions for waste often resulted in considerable nutritional losses compared with intended intakes, from at least 10% to 20% of many macro and micronutrients lost in the lower waste cases (Croatia LOW, Serbia LOC) to a third to almost half in the higher waste cases (Greece LOC & LOW, Italy ORG). For LOC schools across the 5 countries, children were estimated to consume between 63% to 82% of food served, resulting in energy losses between 18% to 35%, protein losses between 17% to 35%, carbohydrate losses between 21% to 37%, total fat losses between 15% to 38%, saturated fatty acid losses of 15% to 37%, and dietary fibre losses of 22% to 38%. For LOW schools, children consumed on average between 57% to 87% of food served, resulting in energy losses of 12% to 42%, saturated fatty acid losses of 14% to 37% and dietary fibre losses of 15% to 43%. Generally, except for Croatia, losses were higher in schools with less sustainable procurement models (LOW/ORG). Overall, Brennan and her colleagues concluded that school lunches often fell well below national and WHO recommendations for primary school children.

Financial and carbon impact

High levels of plate waste correlated with considerable economic loss, with a loss as high as 54% of the total annual supply budget for the LOC model in Greece to the lowest loss of 3% of the total supply budget for the LOW case in Croatia. The total cost of waste across all the countries for the LOC/LOG-ORG procurement models ranged from €21,559 to €85,000 per year. For the LOW/ORG model, total cost of waste ranged from €8,968 to €88,000 per year.

In addition to the economic impact of food waste, the research group also assessed carbon impact. Greece overwhelmingly has the largest carbon impact, with 62% to 63% of total carbon emissions from food procured attributed to plate waste. Carbon impact was generally similar for LOC/LOC-ORG and LOW/ORG procurement models in Greece, Italy and Serbia. Croatia’s LOW model yielded the lowest carbon impact, with only 5% of total carbon emissions from food procurement being attributed to plate waste.

While picky eating is a cliche often applied to young children, the carbon and nutritional impact attributed to food waste may have other driving factors. The length of time available for kids to get their school lunch in eat it varied amongst the schools from 15 to 45 minutes. Students in schools in the United Kingdom only had about 15 minutes to eat their school lunch, or less in some cases since students have to queue to get their food.

“One of the big recommendations of the overarching project is the sense that we need to really think about the service environment in which the children are actually being asked to eat the food,” Brennan said. “We also have to think about the young children’s general environment; how much support are they getting, how much adult supervision, how much encouragement, what sort of rules are in place to require them to eat the food, what sort of cultural practices. These factors vary hugely between our countries.”

Specifically, Brennan and colleagues offered considerations at the national and municipal policy level about the canteen environment layout and food service, lunchtimes and the integration of food more broadly into the curriculum, the role school kitchen staff plays in the educational provision for children, and viewing children as proper consumers who should be eating and enjoying their food. A shift towards a more local, sustainable (LOC) food procurement method is also recommended.

The school lunch area of one of the participating primary schools.

Some of the lunch served to the primary school children.

UK case study: County Durham

It will take some creativity and engagement with students to reverse some of the food waste observed, according to Brennan. For example, one of the sustainable procurement models was at a school in County Durham, UK.

“[The school in County Durham] was very innovative in terms of how they got hidden vegetables into their sauces. For example, when they were making tomato sauces for their pasta or pizzas, that tomato sauce contained a portion of carrots as well.”

In County Durham as well as in other schools monitored, the kids were required to take two portions of vegetables with their school meal (they could not opt out of it). While this did result in more food waste in some cases, it also got the kids to eat more vegetables.

“Lunch is seen as an integral part of how you support educational learning and how you support behaviour. Scotland has universal provision of school meals for primary school children. At the heart of the argument for universal provisional is its ability to help children get through the day. It maximizes their educational attainment during the day, and how you help to control behaviour because if kids are hungry, they won’t necessarily behave well in the classroom,” Brennan said. Food procurement and waste in Scotland is getting more attention recently thanks to the Good Food Nation Act (2022) which promotes sustainable production and procurement in Scotland’s food and drink industry. The UN School Meals Coalition and the Research Consortium on School Health and Nutrition is also prioritizing discussion on improving school food. Creative solutions like those practice in County Durham can make strides in ensuring a nutritiously dense lunch is actually consumed by young children.