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Decaying food waste

BROWN BIN: Tackling food waste at Christmas

Dreaming of a zero-waste Christmas? Looking at the vast volumes of food and drink thrown away every year, it’s a job to know where to start.

This Christmas, the UK will buy some 10 million turkeys, take home around 370 million mince pies and 25 million Christmas puddings, sip 250 million pints of beer, and open an incredible 35 million bottles of wine. But will we eat and drink it all? Hardly.According to WRAP (Waste and Resources Action Programme), the food and drink wasted in the UK increases by a massive 80 per cent over the Christmas period, with a staggering 230,000t of food binned during the festive season. The not-for-profit, government-funded group estimates that this may be worth £275m. This is, however, just the tip of the iceberg.

Every year UK households bin one-fifth of the food and drink they buy. Of the 7.2 million tonnes wasted in 2010 – enough to fill London’s Wembley Stadium about seven times – just over four million tonnes could have been eaten, costing the nation approximately £12bn, and the average household about £420, annually.

What’s more, reports WRAP, the greenhouse gases emitted to produce, process, transport, store, prepare and dispose of all this food and drink are equivalent to 17 million tonnes of carbon dioxide. This equals the emissions of one-in-five cars on UK roads.

Surprised? According to WRAP analyst Tom Quested, even the most diligent of people underestimate how much food they throw away. “Households that stated they generated no food waste actually threw away an average of 90kg per year,” he says.

So what do we throw away? Fresh fruit, vegetables and salad account for around one-quarter of all avoidable food and waste, weighing in at 1,405,000t (see Tables 1 and 2: ‘Top ten foods hitting the bin’).

From this mountain of waste, some 359,000t of potatoes – the largest quantity by weight in this sector – and 190,000t of apples are binned. And as Quested explains in his recent paper published by the British Nutrition Foundation, the total fruit, vegetable and salad loss equates to an average of 0.8 portions of your ‘5 a day’ being thrown away per person, every day.

Bakery products, including bread slices, naan, tortilla and bread rolls, weigh in next at a hefty 782,000t wasted every year. Indeed, WRAP has calculated that consumers throw away seven million slices of bread a day outstripping the 5.1 million potatoes and 4.4 million apples binned and far exceeding the one million slices of ham, 660,000 eggs and 260,000 unopened packets of cheese.

Wasting your five-a-day

According to Quested, most fruit and vegetables are binned because they are not used in time, while other foods are thrown away after being prepared or as left-overs. Either way, decades of low food prices and convenience meals have taken a toll on the nation’s eating habits. Quested says: “On a per capita basis, the over-65s waste around 25 per cent less food than the national average.”

Maybe those remembering wartime rationing are more careful, but how can we curb today’s throwaway culture? Quested believes packaging is key to minimising food waste, and could be improved to help consumers store food more effectively.

“In many instances the environmental impact of an increase in pack weight, for example to re-close a pack more easily, is more than offset by the potential reduction in food waste,” he explains.

Research into date labelling also indicates that some consumers confuse the ‘display until’ dates, used by retailers to control stock, with ‘use by’ dates. Lengthy consultations have finally led to the UK government releasing guidelines on how food packaging should only carry a ‘best before’ or ‘use by’ date, but WRAP is also pressing to change ‘freeze on day of purchase’ labels to ‘freeze before the date marked’.

“Further research shows 59 per cent of respondents thought they could only freeze food on the day of purchase... many would then throw away unopened food if it had been in their fridge for a few days,” says Quested.

The effects of re-labelled packaging on food and drink waste have yet to be seen, but latest waste figures reveal the UK has cut household waste by 13 per cent since 2007. While this is partly down to rising food prices and changes to income, WRAP is confident that consumers are now more aware of the amount and cost of food they throw away and its environmental impact, and are making what they have go further. So, with that in mind, turkey sandwich anyone?

You are what you waste

Claiming to help customers eat more of what they buy, supermarket Sainsbury’s surveyed and categorised 2009 adults according to their shopping habits. Perhaps you’re the ‘Hungry Hoarder’ who shops while hungry, impulse buys and leaves with a trolley of incomplete meals. Or maybe you’re the ‘Ditsy Diarist’, shopping without checking your diary, then eating out and ending up with a fridge of food ripe for only the bin.

Then there’s the ‘Food Phobic’, binning food on or before the best-before date, followed by the ‘Separate Shopper’ who buys without checking what a fellow householder has bought, leading to duplication. If you see yourself here, don’t despair; Sainsbury’s is already providing its ‘in-store counter colleagues’ with tips on how to help us cut waste. And if you don’t? Then you must be either the ‘Freezer Geezer’, frequently freezing potential waste; or a ‘Conscientious Consumer’, skilled at making meals from yesterday’s leftovers.

What about the supermarkets?

Without a doubt, domestic households are the single largest producers of UK food and drink waste, binning 7.2 million tonnes a year, but waste figures suggest supermarkets could also do better. Of the 16 million tonnes of food and drink wasted each year, they produce some 1.6 million tonnes.

Extracting accurate information on waste from businesses in the food industry is difficult, but the CO-OP chain openly publishes its waste statistics, estimating that 25,600t of food waste went to landfill in 2010.

Meanwhile, Tristram Stuart, author of ‘Food Waste: uncovering the global food scandal’, reports that Marks & Spencer throws away around 20,000t of food every year and puts Sainsbury’s waste estimates at around 60,000t.

Stuart is adamant that supermarket waste in unnecessary, highlighting, for example, how a great deal of food is binned simply because its packaging is marked. In a bid to demonstrate this, he recently organised ‘Feed the 5k’ in which 5,000 members of the public were given a free lunch in London’s Trafalgar Square using ingredients that otherwise would have been thrown away by food businesses and retailers.

As Stuart explains, the food was all free and gave the public a glimpse of the vast reserves of food hidden in bins.

The bigger picture

While UK households grapple with their apples, the sheer volume of global food waste from ‘field to fork’ is astonishing. The revelation that up to half of all food grown worldwide is lost or wasted emerged earlier this year as UK government-sponsored Foresight project published its report, ‘Global Food and Farming Futures’. These incomprehensible waste levels take place across the supply chain, from food being grown, processed, supplied and bought, to then being discarded by the consumer.

As Hannah Johnson from Resource Futures, a UK consultancy that led the report’s research into global food waste, says, these losses are simply not sustainable given the immense pressures on the global supply chain. Worldwide population is predicted to rise from seven billion to nine billion by 2050, competition for land and water is intensifying, and climate change effects are emerging. And the pain doesn’t stop here.

“Agricultural systems depend on phosphate fertilisers [derived from mined phosphate rock],” says Johnson. “However, researchers [from the Global Phosphorus Research Initiative, a collaboration between independent research institutes in Europe, Australia and North America], predict a global peak in phosphate rock reserves in 30 years. This will be a massive thing.”

Clearly, addressing waste across the entire food supply chain is critical but, as Johnson points out, preventing waste from households, rather than dealing with its disposal, is a priority, especially when the emissions produced during its production and supply are taken into account. “If you compost this waste rather than putting it into landfill, you save around one tonne of carbon dioxide per tonne of food,” she says. “But if you prevent the food waste from happening in the first place, you save 4.3t of carbon dioxide per tonne of food [compared to landfill]. Prevention is far better, and to do this, we need to educate householders [with help from] the entire supply chain.”

Focusing on the undernourished

However, the problem is not the same the world over. While developed nations accrue most food waste at the consumer, developing nations suffer more food losses during distribution and storage due to inadequate infrastructure. Put simply, what little food reaches these consumers is eaten.

In a bold attempt to tackle the world’s vast and varied food waste issues, the Foresight project highlights ways low-income nations could reduce post-harvest waste and high-income countries could cut consumer waste. The contrasts are stark; provide farmers in developing nations with sealed storage drums in which to store grain yet encourage food producers in developed countries to integrate sensors into packaging so consumers can detect when a refrigerated product is nearing its use-by date.

The report also compares the nearly one billion starving with the one billion that are over-eating, causing an epidemic of obesity-related illnesses. As Johnson concludes: “We’ve got more people in the world that are overweight than undernourished. It’s not as simple as shipping mangoes but if we could send those nutrients to the undernourished rather than the overweight, we might not have a global food problem at all.”

Help at hand

The ‘Courtauld Commitment’, a WRAP initiative first launched in 2005 to reduce food and packaging waste in the UK grocery sector, has signed up 53 food producers and retailers. Each has developed new methods to help consumers cut waste.

Waitrose, for example, reduced the thickness of its prepared salad bags without, it claims, lowering quality and reducing shelf life. Meanwhile, Molson Coors Brewing Company unveiled recipes using Christmas Day leftovers, including Brussel sprout bhajis and Christmas Pudding naan, that apparently compliment its Cobra Beer.

But while the Boxing Day Brussel sprout bhaji may not have mass appeal, the scheme has produced results. In September last year, WRAP claimed 1.2 million tonnes of food and packaging waste – valued at £1.8bn – had been avoided between 2005 and 2009. This, says the organisation, cut carbon dioxide equivalent emissions by 3.3 million tonnes, the same as stopping half a million around-the-world flights.

Eating out and the cost of leftovers

Waste doesn’t just come from the home. According to the Sustainable Restaurant Association (SRA), a not-for-profit organisation aiming to make restaurants and diners more sustainable, for every meal eaten in a UK restaurant nearly half a kilo of food is wasted through preparation, spoilage and what’s left behind on the plate.

Based on a survey of London-based restaurants, the organisation estimated the UK’s 27,153 restaurants throw out some 600,000t of waste a year, which is around 22t per restaurant. Admittedly, the numbers surveyed were small – only ten – but their waste figures were big, and as Tom Tanner from the SRA highlights, the restaurateurs were left very surprised.

“The volunteer restaurants represent a broad spectrum of restaurant types and provide an average representation of food waste in the UK,” explains Tanner. “The vast majority of people, about 75 per cent, had no idea how big their problem was.”

In terms of where waste was from, the survey revealed 65 per cent came from food preparation – peelings, off-cuts, or anything ruined during cooking – while 30 per cent came back from customers’ plates. Meanwhile, 5 per cent of waste was classified as ‘spoilage’, out-of-date or unusable items.

Importantly, however, the SRA is confident the average restaurant could cut waste by 20 per cent and save £2,000 per year by simply applying ‘traditional housekeeping’ such as leaving skin on potatoes and using entire chickens, not just the breast. And as Tanner also points out, the restaurant would also save up to £1,700 each year on waste collection costs, a saving that will only grow as waste pick-up fees rise with landfill tax.

To drive the point home, the organisation has just launched its ‘Too Good To Waste’ campaign which kicked off by supplying restaurants with ‘doggy boxes’, to encourage diners to take leftovers away with them. Tanner is well aware the doggy box alone will not solve waste issues but hopes it will alert more of the public to the problems.

“Think of older generations that lived through the war with rations,” he says. “It’s only when we got to the 1980s we started thinking we almost have this divine right to buy as much as we want and order what we want in a restaurant, without really thinking about the consequences.”

Food and waste disposal for free

Fareshare prides itself as a food supply organisation for the needy that is at the centre of two urgent issues; food poverty and food waste. Operating since 2004, the UK-based charity redistributes surplus food from supermarkets and food manufacturers, such as Sainsburys, Nestle and Sodexo, to community organisations including night shelters and women’s refuges.

As communications manager Maria Kortbech-Olesen explains, food could be passed its display-by date, stock that can’t be delivered due to adverse weather conditions – last winter’s snow saw a peak in supply – or packaged incorrectly. Whatever the source, the results are impressive.

“Last year we collected 3,600t of food and drink, which contributed to 8.6 million meals,” says Kortbech-Olesen. “We work with 700 UK organisations, have a waiting list of other charities that need support, and only get 1 per cent of edible food waste; there is much more food that we can tap into.”

Joining the two together is a matter of funding but the charity is now implementing a business model that could help this happen. The businesses that provide food are actually getting to dispose of surpluses for free, so why not charge a fee?

As Kortbech-Oleson points out: “We provide them with a service that benefits the environment and community, makes good use of their surplus food, and is cheaper than landfill.”

From food waste to fuel

When Professor Keith Waldron of the UK-based Institute of Food Research first investigated why water chestnuts could keep their ‘crunch’ even after cooking, he probably would not have expected to be opening a £350,000 biorefinery centre some 15 years later. Waldron’s initial studies explored the role of cell walls in a plant’s structure and he has since devised techniques to extract sugars from the cell walls of food crops and convert them to bio-alcohols for use in transport fuels.

“Once the food part of a crop has been exploited, there is a mass of plant material left behind that is often discarded as waste,” explains Waldron. “We’ve developed a bio-refinery approach in which we convert waste biological matter into ethanol. So if a company has a waste stream that costs them money to get rid of, we can transform it into something else and avoid the disopsal cost.”

Waldron’s primary focus at the newly-opened University of East Anglia facility is to extract cellulose from wheat straw as wheat is produced in large tonnages in the UK. Once extracted, cellulose can be degraded with enzymes so the glucose that is released can then be fermented to ethanol. But while this sounds relatively straightforward, the cellulose in the straw is locked inside a complex structure of lignin, a polymer that fills the spaces within straw’s cell walls, strengthening the cells and plant itself.

“There is only one way to liberate the cellulose so it can be digested,” explains Waldron. “We have to blast apart the cell walls.”

And this is where the new steam explosion pre-treatment facility is crucial. By placing waste material inside its reactor and ramping up the pressure and temperature inside, researchers can rupture plant cell walls and liberate the cellulose ready for conversion to ethanol. The ethanol produced is then passed onto industry partner Lotus Engineering for testing in a range of engines.

“As well as waste streams from food processors and field-waste, we are also looking at municipal waste, which includes food waste that would otherwise have ended up in landfill.” says Waldron. *

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