The traffic light-style grading system - ranging from red G to green A+ - was developed by scientists at Oxford University to help consumers choose more sustainable goods and encourage more innovation.
It takes account of each product's impact on the environment - including carbon emissions and water pollution - over its whole life cycle from farm to shop.
The pilot is being launched by the non-profit organisation Foundation Earth, which was created by Denis Lynn, the food entrepreneur who died in a quadbike accident in May.
It is backed by Nestle, the world's largest food company, as well as M&S, Co-op, Sainsbury's, Costa and Tyson Food, and will initially run on selected ranges from Finnebrogue Artisan, White's Oats, Mighty Pea and Mash Direct.
The scheme also has the support of both the UK government and the Labour opposition and is expected to run until early in the New Year.
Environment secretary George Eustice said: "Foundation Earth’s ambitions to develop eco-labelling on food has the potential to help address the urgent challenges of sustainability and climate change."
Shadow environment minister Luke Pollard said: “People want to do what they can to tackle the climate crisis and help the environment. But at the moment they don't have the information they need to make more sustainable buying choices.
"I want to see clearer labelling on carbon and environmental credentials so people can back the brands and products doing the right thing by our planet.”
Foundation Earth is hoping to move to a full Europe-wide rollout in 2022.
Andy Zynga, the chief executive of the EU-funded initiative EIT Food, which was involved in developing the eco scores method, said the launch was "a very significant moment for the European food industry".
He added: "It will bring about a credible and clear front-of-pack environmental labelling system on food products right across the continent.
“In supermarkets throughout the European Union, consumers are trying to make more environmentally-friendly choices - and food is at the heart of this."
The global food industry already contributes up to 37 per cent of greenhouse gas emissions, according to the UN’s intergovernmental panel on climate change, and that figure is set to rise further by 2050 as a result of population growth.