Pigs are perhaps the original solution to the problem of food waste, but one that current farming practice and legislation has put out to graze. Indeed, it was their voracious appetite for our leftovers and offcuts that was one of the main reasons humans first domesticated pigs, and for centuries they helped to make sure that little went to waste. In the last hundred years, cheap grain reduced pigs’ role as waste disposers, but it was the 2001 foot and mouth outbreak in the UK that led to swill kicking the bucket.

In the wake of the epidemic, which paralysed the British countryside, cost billions, and led to a cull of perhaps as many as 10 million animals, enquiries tentatively traced its source back to an intensive pig farm in Heddon-on-the-Wall, Northumberland – although suspicions remained that the disease may have been present in the sheep population for months before the outbreak was identified. The cause, according to the then Ministry of Agriculture, Fisheries and Food (which was replaced by Defra), was the pigs illegally being fed unprocessed swill containing contaminated meat from restaurants. The ban therefore was a result of a farmer breaking the law – not the result of the law being wrong.

After this case, there was a complete ban on the use of catering waste in swill. It started out as a temporary measure but is now enshrined in European law and incorporated into law in England through the Animal By-Products Regulations made in 2003 and 2011. That was the end of pig buckets in kitchens – but the impact was far wider. Lack of clarity about the law has resulted in a big decline in the safe and legal use of other food waste as pig feed, such as spent hops from breweries, whey from dairies, and surplus bread from bakeries, though there are some notable exceptions, such as one major supermarket diverting all its bread waste for animal feed.

Most pigs today eat feed made primarily from crops like soya, maize and wheat, which has a range of lamentable consequences. For starters, it’s expensive, and increased costs seem to be one of the reasons why the number of pigs being farmed in the UK has decreased dramatically, from 8.1 million in 1998 to 4.8 million in 2007. We now import 60 per cent of our pork from countries with far lower animal welfare standards and traceability measures.

Feeding crops to pigs also means that they’re not available for humans to eat: the United Nations estimates that if farmers around the world fed their livestock on agricultural by-products and the food that we currently waste, it would save enough grain to feed an extra three billion people. What’s more, much of Europe’s livestock feed is made of soy and other cereal crops grown in South America, where additional land is being cleared – including precious Amazonian rainforest. European import of soymeal increased by almost three million tonnes in the two years following the pigswill ban.

There’s also the problem of disposing of the food waste that might have been eaten by pigs instead – if it ends up in landfill, it produces methane as it rots, contributing to global warming. Moreover, disposing of food waste costs its producers money, and though composting and anaerobic digestion (AD) are environmentally preferable to landfilling food waste, the carbon benefits of feeding food waste to pigs can be around 20 times greater than sending it to AD plants. The UK formerly had successful pig swill businesses, which were paid a small amount to take food away; after treating it to make sure it was safe, they were able to sell it on to farmers at up to £160/tonne. Now, food waste costs farms far more, with conventional grain coming in at around £400/tonne.

Where there’s a swill…

Who would have thought that how we feed pigs could have such widespread ramifications? The case for feeding non-ruminants on food waste that they can safely eat seems obvious – but someone needs to make it. That’s where The Pig Idea comes in, to demonstrate that, so long as it’s done properly, it’s safe and healthy to put food waste back on the menu for British pigs.

Last year, we raised eight pigs at East London’s Stepney City Farm on a diet of food waste that is entirely legal under the current legislation. They tucked into a tofu by-product called okara, brewers’ grain, whey, and off-cuts from fruit and veg suppliers. Each company that supplied food to Stepney had to be registered, and had to track and log its food waste to demonstrate that there is no cross-contamination with animal by-products. All this is absolutely legal, and, what’s more, these types of food waste don’t even need to be processed.

They say the proof of the pudding is in the eating, and the same is perhaps true of pigs. Some of the UK’s best-known chefs gathered in Trafalgar Square on 21 November 2013 to prepare their favourite pork dishes using the meat from our little herd, as part of The Pig Idea Feast. We served over 5,000 portions of food to the public for free, and as a result over 7,000 people have signed The Pig Idea pledge to reduce their own food waste, whilst simultaneously calling for food retailers to adhere to the food waste hierarchy. The idea was to restore public confidence in the safety of feeding surplus food to pigs, and to promote understanding of this efficient, cost-effective and environmentally-friendly practice amongst food waste producers.

As well as highlighting what is possible within the law as it stands, we’re also lobbying for a change to European law so that pigs can return to their traditional role in managing food waste, and we are already seeing some progress.

Swine of progress?

In 2013, the Food and Agriculture Organization of the United Nations released a report demonstrating the safety and effectiveness of using fruit and vegetable waste for livestock feed. Similarly, a recent Defra-commissioned report, ‘Recycling of catering and food waste’, found the benefits of processing food waste for animal feed were comparable in value but more likely to be achieved than those of AD.

AD can, of course, be a valuable source of energy, but surplus food and food waste should be managed in line with the food waste hierarchy. This means that, where possible, surplus food should be donated to food banks for consumption by humans. But if foods for which there is no human demand, such as bruised fruit and veg, whey, brewers’ grain, and indeed catering waste, are going to waste, the first preference is for it to be used as animal feed where practicable. The animals’ manure can then be put through AD, along with any foods that aren’t suitable for animals.

One of our challenges is to make sure that the enthusiasm we’re trying to foster doesn’t get out of hand, initially focusing on making better use of food waste that is safe and legal to feed to animals, and providing guidance to farmers and food waste producers to make sure they understand the benefits. Once we’ve made progress with that, the ban on catering waste should be revised and lifted, to allow for the establishment of a robustly-monitored food waste industry – meaning swill wouldn’t be prepared in the back yard in ways that risk spreading disease.

It’s also important to be clear that, when it comes to catering waste that may contain animal by-products, this should only be fed to omnivorous non-ruminants, such as pigs and chickens. The ban on feeding animal by-products to ruminants such as cows and sheep (which was introduced in response to the emergence of mad cow disease) should remain in place.

If we are going to raise animals for food, they should live well and be fed sustainably. Killing animals for meat in this country should not result in a butterfly effect that sees animals dying on the other side of the planet as their habitats are destroyed to make space to grow feed. Our reticence to make safe use of food waste as pig swill may stem from genuine concerns, but we need to recognise it as an overreaction. It is time to make a change: let them eat waste.

Edd Colbert is campaign coordinator for The Pig Idea: thepigidea.org

This article is a version of an entry that originally appeared on the Isonomia website. For more, visit: www.isonomia.co.uk