An unripe mango has helped inspire an Edinburgh graduate’s research that shows we can all help tackle climate change by taking control of our own food choices. Image Dr Stephen Porter had already clocked up 20 years working in financial services when he decided to return to university to take the masters in Carbon Management at Edinburgh. It was 2012 and the increasing global focus on the environment and sustainable living motivated him to refocus his career path. “I wanted to take a new route that would allow me to look at how economic and financial decisions were affecting the planet and its climate,” he says. “I found the masters course to be intense, but in a good way. I became engrossed in finding out about areas of the economy and society that use resources less efficiently and more wastefully than others – the agri-food supply chain being one of those.” So after gaining his MSc, Stephen began work on a PhD study under the mentorship of three colleagues from the Schools of GeoSciences, Social and Political Science, and Education. Their aim was to investigate the quantity, drivers, and mitigation potential of greenhouse gas emissions embedded in food wastage. “We basically set out to show that addressing these inefficiencies could lead to marked improvements not only in our impact upon the climate but also potentially on society,” says Stephen. “Inefficiency goes hand in hand with inequality – defining where it exists can in turn lead to fairer distribution and consumption, which has important implications for developing countries. So our work was as much about finding ways to reduce wastage as it was about pinpointing where they occur.” Food choices Image But it was a moment of inspiration in a supermarket that sparked one of the study’s key lines of investigation, whose findings captured the imagination of the national media, too. Stephen explains: “I picked up a perfect-looking mango that was reduced in price because the supermarket’s ‘best before’ date had been reached. I bought it and took it home to my wife, who is more knowledgeable about mangoes than I am. She burst out laughing - the fruit was still so green and hard that she said it was unripe and completely inedible, definitely nowhere near its ‘best before’. It was another two weeks before it was ready to eat. “This simple event got me thinking about how some of the most tasteless fruit I have ever eaten has been the most ‘perfect’ in terms of appearance, shape, size, and feel. So I thought about the impact this is having on food choices we make, and the choices we are not allowed to make because retailers, regulators, and society make them for us. What was being sacrificed and wasted due to our preoccupation with aesthetic perfection?” Ugly fruit Stephen and his team then decided to examine how much food is discarded within the European Economic Area each year before it reaches the point of sale. They found up to a third of fresh fruit and vegetables never makes it to shop shelves because of purely cosmetic ‘reasons’ of being misshapen or the wrong size – so called ‘ugly’ fruit and vegetables. Their study estimates that over 50 million tonnes of fresh produce grown across Europe is discarded annually, mainly because it does not meet supermarkets’ and, indeed, consumers’ standards of how it should look. In the UK alone, the figure stands at up to 4.5 million tonnes. A shocking statistic at a time when one tenth of the world’s population is perpetually underfed. “The food distribution sector in Europe and the UK is oligopolistic in nature,” says Stephen. “A small number of supermarket chains control a large market share, and their influence enables them to impose additional proprietary ‘quality’ criteria. “So produce that doesn’t meet these standards may be lost from the food supply chain, never seeing a supermarket shelf – it may not get past the supplier, or even leave the farm.” Image Our hunt for perfection has led to an increase in fresh fruit and vegetable wastage. Less picky The climate change impact of growing the wasted food – some of which may be ploughed back into fields, used in animal feed or otherwise reused – is equivalent to the carbon emissions of almost 400,000 cars. But Stephen believes that greater awareness among consumers is crucial to addressing all of these issues and, along with the movement towards shopping more sustainably, could encourage the sale of more “ugly” fruit and vegetables. He was heartened by the media attention his research has attracted, too, and hopes public attention will lead to a greater use of misshapen produce, perhaps in chopped or processed goods, or for sale at a discount. “Encouraging people to be less picky about how their fruit and vegetables look is crucial,” says Stephen. “It really could go a long way to cutting waste, reducing the impact of food production on the climate, and easing the food supply chain.” Stephen's tips We asked Stephen to suggest ways that Edinburgh Friends readers could reduce their own food wastage. Here are his eight tips: • Make a menu plan for the week. • Only buy the amount you need for the menu plan. • Keep leftovers and be creative in how you re-use them. • Organise our fridges, freezers, and pantries to know when food should be consumed. • Learn how different foods may be combined, recombined, and/or repurposed. • Choose food based upon your palate and not solely with your eyes – this requires understanding your food choices better. • Visit a farm shop and have a taste! Learn from the professionals about the natural variation of fresh produce. • Beauty is in the palate of the beholder! Wider research Stephen and his team's wider research concluded last year with a thesis that included four peer-reviewed articles. Among the most vital outcomes, they found that: 5.7% of UK carbon emissions attributed to milk production are avoidable. The figure is about 2.5% globally. The embedded emissions of global food wastage increased more than 3-fold in the 50 years until 2011. Emissions grew more quickly than the wastage itself, implying a change in production and dietary preferences towards more emissions-intensive foods. Per capita, food loss and waste emissions increased in developing regions but were stable-to-decreasing in the developed world. Deliberate withdrawal and destruction of fresh fruit and vegetables from the food supply chain through EU Common Agriculture Policy mechanisms amounted to the equivalent to about 2% of EU fresh fruit and vegetable production, and 0.15% of emissions from managed soils in the EU. Despite changes to policy resulting in a 95% reduction in such withdrawals, the proportion of withdrawals typically destroyed remained consistent at about 60%. This suggests that institutional barriers are preventing access to non-retail sales opportunities. About 7% and 14% of farm soil emissions in the UK and EEA respectively are a result of the application of cosmetic standards to fresh fruit and vegetables. Related links Research @ GeoSciences Global Challenges Planetary Health Alumni Initiative This article was published on 2023-11-10