We all know about the households that supposedly throw away half their weekly food shop and the ‘freegan’ bin divers who gather behind supermarkets at twilight to forage for out-of-date but still edible food that’s been thrown away.

UK households amass around 5kg of food waste per week with nearly two thirds being avoidable waste, according to a new report by the Global Food Security (GFS) programme. Of the 15 million tonnes of food wasted every year in the UK, nearly half is discarded by households.

Who wastes what where?

1: At the production stage agricultural losses of 15% to 20% are incurred as a result of pests and diseases.

2: Retailers can reject up to 40% of edible products due to their aesthetic standards.

3: Food losses from within distribution and retail account for just 3% of total losses.

4: Three-quarters of food waste in the UK occurs at the consumer stage. This equates to an £11.8bn economic loss.

Source: Global Food Security

These are huge figures in themselves, but depressingly, they are just just the tip of the waste iceberg. Look further down the chain and a far broader waste stream flows through our ever-more globalised food system. It begins in the banana plantations in Jamaica, the feed lots of the Americas and the fisheries of Europe and ends up in the fruit bowl, or the fridge, at home. Its scale - measured in gigatonnes - is hard to visualise but the percentages are not.

According to a new report from the United Nation’s Food and Agriculture Organization, the world wastes a third of the food grown for humans.

In one sense, such abundance is a triumph of science and enterprise but such prodigal waste is also a source of economic, social and environmental shame costing £470bn a year and 3.3 billion tonnes of carbon emissions. That’s equivalent to “the third top carbon emitter after the USA and China”, says the UN report, with further impacts on other ‘externalities’ such as water resources and biodiversity.

Tristram Stuart, campaigner and author of the book Waste: Uncovering the Global Food Scandal, believes the final figure is actually higher still - perhaps half of all food never reaches the mouths it was intended for, he says. He travels the world and has witnessed what this means close-up. “I’ve seen mountains of bananas being wasted in Ecuador and 50 tonnes of food fit for consumption wasted at one depot in Kenya where people are starving.”

“I’ve seen 50 tonnes of food fit for consumption wasted at one depot in Kenya where people are starving”

Tristram Stuart

In just one case this year, Stuart says he saw Kenyan farmers waste 40% of a bean crop because it didn’t meet the supermarkets’ aesthetic standards on size and shape. “The supermarkets seem to have little understanding of the colossal food waste their standards cause,” he says bitterly. “It’s a tragedy and there’s a huge opportunity to reduce the impact on the environment and the pressure on food supplies.”

The good news is that retailers and producers are waking up to the problem and taking action. The Courtauld Commitment, which is led by anti-waste body Wrap and has more than 50 large companies signed up to it, will soon report on its efforts so far to cut household food waste by 4% and grocery product and packaging waste in the supply chain by 5% between 2010 and 2012. The third phase of the commitment, launched this May, seeks to reduce household food and drink waste by a further 5% by 2015.

Stuart concedes that progress is being made. “One of my favourite success stories is the sale of ugly fruit and veg and the investment made into processing it or marketing it directly to people.”

The investment has clearly paid off. ‘Wonky’ fruit & veg has been the fastest-growing sector in fresh produce since 2009, according to the British Retail Consortium, and in the last 12 months the NFU estimates that it has saved 300,000 tonnes of UK produce from being wasted. But Stuart would like to see far higher levels of take-up. “We want to see that as permanent change and see that figure expanded,” he says.

Asda chilled

The retailer: Asda

As part of the Wrap-led Courtauld 2 commitment, Asda has been working to deliver fresher products to its customers by implementing efficiencies to its delivery and store systems.

In what it describes as the “biggest change programme” within chilled for 15 years, the retailer has increased the shelf life of 1,572 chilled products by an average of one day.

That extra day offers two advantages when it comes to cutting food waste - it gives Asda longer to sell these ranges, but it also gives its customers longer to consume them, so cutting the risks of waste.

To add the extra 24 hours, Asda worked with 407 suppliers to reschedule inbound flows, improve delivery plans to cut down on road miles and develop new and simplified systems in-store to get products to shelf faster and support better stock rotation.

The initiative has reduced supplier-to-depot lead times and improved the flow of products into depots. It has also achieved a 3.7% drop in the number of chilled loads to store.

“This was the biggest change programme within the Asda chilled supply chain for 15 years,” says Tom Rose, Asda’s inbound supply chain manager.

“It has had a significant impact on the freshness of products to our customers as well as a positive environmental impact. It just shows what can be achieved within the end-to-end supply chain when all parties work together.”

The eco-friendly changes resonate with its shoppers, adds Asda.

“A study carried out in 2011 showed that 70% of customers care about being green - but our most recent 2012 study showed that number had increased to 81%” said a spokesman.

“And the two words our customers used most to describe people who recycle, and use less energy and water, are ‘normal’ and ‘intelligent’.”

Retailers and food producers are also donating greater quantities of fit-to-eat food they cannot sell to charities such as FareShare, which last year redistributed 4,200 tonnes of food, enough for more than 10 million meals.

It expects to increase this by between 30% and 40% this year, says director of food Mark Varney, although this would still represent only a fraction of the total available. “We believe that there is between 300,000 to 400,000 tonnes of surplus fit-for-consumption food currently thrown away in the UK each year,” he says. “In France they redistribute 100,000 tonnes of food. We are proud of what we have achieved, but there’s no reason we can’t do what the French are doing.”

In Varney’s view, the UK can reach these sorts of tonnages if businesses and their supply chains embed the donation option into their processes, following the examples set by retailers and suppliers including Sainsbury’s, Asda, Tesco, the Co-operative Group, Gerber and Nestlé. “It just requires collaboration between different functions or across organisations and management capacity.”

FareShare shows the way

FareShare’s processes are robust enough to give other supermarkets and food groups the confidence they need to donate, says Varney. “A big part of our work is checking charities that are the recipients of the food, making sure it does not end up on a market stall, for example. We do a lot of work to manage that process.”

Achieving regular supplies will create a virtuous circle that boosts demand and diverts much more food from entering the waste stream, he argues. “Being able to plan forward is really important to us. If we can say to the charities ‘you can rely on us’, we will create more demand.”

“It is eight times less environmentally friendly to send food for recycling than it is to donate it”

Mark Varney, FareShare

Being able to soak up this surplus supply benefits everyone, he adds. “We turn the negative of waste into a positive outcome. We are saving charities an awful lot of money and food distribution also acts as footfall driver for them,” he elaborates.

“If there are good things to eat in a homeless shelter, for example, people are more likely to visit and talk to a counsellor and tackle their problems. It is also eight times less environmentally friendly to send the food for recycling than it is to donate it.”

Of course, however efficient a supply chain is, there will always be some wastage. So there is still a role for the recycling of food waste that is unfit for human consumption, either as animal feed, fertiliser or biomass.

The industry is already sending 550,000 tonnes of food a year for animal feed, and anaerobic digestion technology is now proven and mature, says Mike Read, head of waste at Grant Thornton. “You get the benefit in terms of electricity or heat out of the waste, or by turning into biofuel as well as a digestate, which with the right quality controls can produce a cheap and acceptable alternative to man-made fertilisers.”

Olam

The producer: Olam

Olam, an integrated supply chain manager and processor of agricultural products and food ingredients, has a sourcing and processing presence in most producing countries across the globe - so even small changes to the way it does business can have a significant impact.

In a bid to improve its sustainability and reduce waste, it has implemented a twin-pronged strategy to help its suppliers deliver a greater proportion of usable produce and use the waste generated in the production process for other purposes.

It is working with small-scale cocoa producers in West Africa, for instance, to bring groups of smallholders together and help them invest in solar driers, facilities to grade the cocoa and training based on best agreed practices to help them get beans dried to a reasonable standard.

“Often, it’s all about how quickly you get from the farm and into the processing unit,” says Chris Brett, Olam’s head of corporate responsibility and sustainability. “The quicker you get produce into the supply chain, the more you can reduce waste.”

The cocoa initiative is just one example of linking and aggregating smallholders to help them produce less waste and there are myriad other opportunities such as reusing inevitable and unavoidable waste - for example, taking spent coffee grounds and converting it to fuel to be used in the boilers at processing plants.

“We’ve seen a huge rise in agricultural waste used in farming, for example tomato waste being used to improve the nitrogen content of soil, waste coffee pulp for growing mushrooms and certain waste products used for biomass such as cashew nut hulls,” adds Brett.

“And when you reduce environmental impacts, you reduce costs, too.”

Challenges such as fragmented supply do remain, however. While large-scale food groups can build their own on-site facilities, later in the supply chain there’s a need for guaranteed feed stock collection to justify building standalone facilities, says Read.

Segregation of food waste from retailers, the hospitality trade and households is patchy and local authorities are not acting in concert to create economies of scale when it comes to food waste streams, he adds. “You need to create the incentives for someone to take the risk to build a facility, and you have to have someone to collate the material.”

The Welsh Assembly is providing a degree of leadership here, creating collection hubs and helping support anaerobic digestion projects financially, says Read, but there has been no comparable support from Defra.

And while technological fixes like recycling or digestion do contribute to better management of food waste, they will never achieve the cuts needed, says Stuart. “Chucking food into a composter is not the best use of something that could be feeding people. Food donations have become much more acceptable, but what’s being donated is only a fraction of the waste out there.”

Waste should be halved

Much greater efforts are needed to make a significant dent in the mountains of waste the world produces, says Stuart. “We can change these markets. They are not inflexible, but we need to see a significant ratcheting up of the level of engagement we’ve seen so far. There are good examples of dramatic waste reduction over the last few years. There’s no reason why we can’t all aim for the UN and EU call for a halving of food waste.”

Stuart acknowledges that attitudes are changing. “Supermarkets are beginning to turn their attention to food not just wasted in their own stores but to take responsibility for food waste caused by policies, even if it is not happening at their own gates. That’s the way some of most powerful food businesses can change what’s happening.”

Chris Brett, head of corporate responsibility and sustainability at Olam International, a leading supply chain manager and ingredients processor that serves customers such as Unilever, Nestlé and Costco, attests to the whole supply chain approach being adopted by retailers and suppliers in a bid to cut waste. “The big food groups are pushing targets onto us,” he says. “They are measuring this now. The biggest innovation has been joining up the whole supply chain.”

Companies have been urged to do this under the Carbon Disclosure Project and a new module that includes the supply chain will increase the pressure to better measure, account for and ultimately reduce waste, he says. “Products like biomass will get a value and we will see waste being used much more local to its source as an important fuel or as a substitute for something else.”

Olam is developing multiple initiatives along these lines with its suppliers to cut waste (see right), but while such innovations are gaining momentum ,”more needs to be done to integrate such fragments of ingenuity”, contends Brett. “Actively collaborating and sharing ideas, resources and investment between food producers, manufacturers, buyers and even governments to pinpoint and maximise every tiny opportunity from farm to fork will help to create a bigger impact.”

Only then will the industry have a fighting chance of hitting the UN’s target and putting an end to this global food waste scandal.