By Robert Durant

A typical summer barbecue* releases as much greenhouse gases into the atmosphere as a 60 mile car journey, according to a group of scientists studying the impact of food choices on the environment.

Scientists from across the UK have come together to shine a spotlight on how consumer decisions on diet, as well as new technologies, could help reduce global warming.

Their work is being showcased this week at the Royal Society Summer Science Exhibition (1-7 July 2019) in London. The ‘Take a Bite out of Climate Change’ exhibit will take visitors on a journey from ‘farm to flush’ to explore GHGE at all stages of food production, processing, supply and consumption.

It follows an announcement by Prime Minister Teresa May that the government will commit to cutting greenhouse gas emissions (GHGE) to ‘net zero’ by 2050.

The team, led by the University of Manchester, brings together academics from food resilience programme N8 Agrifood and innovative technology solutions from the STFC Food Network+. The exhibit will feature innovation in food production by the National Centre of Food Manufacturing at the University of Lincoln, Entocycle, LettUs Grow and Hodmedod’s, with underpinning research from the Universities of Lancaster, Sheffield, Manchester and others.

Lead scientist, Professor Sarah Bridle, said: “Food contributes over 20% of all greenhouse gas emissions. As the barbecue season gets underway, people might like some food for thought about the impact of their choices on the environment.

“Did you know for example that a 100g medium-sized beef burger releases enough greenhouses gases to fill more than 60 balloons? That’s equivalent to driving about 15 miles in a car. By switching to chicken you could reduce that to less than 15 balloons.

“Did you know that a portion of strawberries would release enough greenhouse gases to fill about five balloons, but this would rise to about 10 balloons on adding two tablespoons of cream, or to over 20 balloons if flown in out of season? And each bottle of beer causes emissions equivalent to about 10 balloons full of greenhouse gases.

“By making a few small changes to our diets such as swapping beef for chicken or a vegetarian alternative, a fizzy drink to tap water, a cheese sandwich to a peanut butter sandwich, or a fry-up breakfast to porridge we can make a significant impact.”

The group of scientists has calculated that a typical barbecue* would release the equivalent of about 225 balloons of carbon dioxide per person, equivalent to each person driving 60 miles; whereas a lower emissions barbecue* – where beef burgers were replaced with chicken – would emit approximately 125 balloons of greenhouse gases.

A vegan barbecue*, where meat was replaced with vegan sausages, cheese was swapped for onion, butter was swapped with vegetable spread and cream was switched to sugar – would reduce the emissions again, causing the release of the equivalent of about 80 balloons of carbon dioxide for the whole meal, which corresponds to driving about 20 miles per person, and is less than half of the typical barbeque emissions.

The ‘Take a Bite out of Climate Change’ exhibit aims to raise awareness of the innovative ways that cutting edge science is transforming food production, including vertical and precision farming techniques, tools to measure soil emissions and improvements in supply chain efficiency and resilience using blockchain, Internet of Things and cryogenics.

The scientists also hope fascinating data about consumer food decision making gathered from a project on people-powered online research platform Zooniverse, will encourage visitors to make behaviour change pledges.

Dr Helen Downie, who is co-leading the project has called on consumers to demand the latest information on environmental impacts from food producers, to enable them to make fully informed choices and motivate food producers and retailers, to lower their emissions.

Visitors to the exhibition will be able to test their knowledge by playing a computer game to guess the greenhouse gas footprint of different foods and play a game to learn about how food production can be improved to reduce emissions on farm.