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The Raelian Movement
for those who are not afraid of the future : http://www.rael.org
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Source: http://www.newscientist.com/article/mg21628923.600-extreme-recycling-turns-poo-into-food.html?full=true
Extreme recycling turns poo into food
IT'S extreme recycling. Why grow crops on manure when you could just take the good stuff directly from it? Even better, maggots could help.
Global food prices have soared in recent years, and animal feed is no exception. "Maggot cake" could provide a high-protein food source for farm animals that is not only readily available, but recaptures nutrients in manure and other waste far more efficiently than existing methods.
"The real story is that we are mining an unexploited resource, and what's the last great unmined resource? It's our own waste," says Howard Bell of theUK Food and Environment Research Agency in York. With demand for food growing, "anything that can address a looming protein crunch is a good thing", he says.
Bell and other researchers are investigating the potential of growing maggots on manure, food and brewery waste. Once they have grown fat, the maggots are harvested, dried and crushed into a protein-rich powder for feeding to chickens, fish, pigs and other farm animals.
European farmers currently import 80 per cent of their animal feed, mainly soy from South America. US farmers face a feed crisis too. For example, the price of maize fed to pigs in the US has trebled since 2007. That's because new regulations and subsidies introduced at the time made it more profitable for maize growers to sell their crop for biofuel, reducing the supply for farmers.
The idea of harnessing maggots to address this problem is gathering pace. Much research has already been done in the US, South Africa and Spain, and next year could see the first commercial plant, probably in South Africa. Meanwhile, a US company called OVRSol is in talks with a major international food company to fund a pilot plant, followed by a full-scale commercial facility.
So exactly how much protein can be extracted from waste using maggots? Bell has been feeding chicken manure to housefly maggots as part of athree-year project. He says that at the moment, a tonne of manure yields about 100 kilograms of larvae, from which he can produce between 12.5 and 35 kg of feed.
The product is as rich nutritionally as the soy and fishmeal currently used as animal feed, Bell says. He presented his preliminary results last week at aconference in Edinburgh, UK, adding that he is confident of raising yields further by adjusting factors like the air and water content of the manure.
Allan Finney of OVRSol says his firm intends to feed its black soldier-fly maggots on waste from the food industry at first, and then on manure. Tests by the company suggest that the larvae can reduce manure to half its original volume, and because they outcompete and consume bacteria such as E. coli and Salmonella, the manure doesn't putrefy and essentially gets sterilised and deodorised. It can then be used as compost.
AgriProtein based in Cape Town, South Africa, is close to raising the funds it needs for a full-scale factory next year. Rather than manure, it feeds housefly maggots on a mixture of abattoir blood and bran, says company founder Jason Drew. He thinks the factory could produce around 100 tonnes of maggot cake a day.
Because the protein content of maggot cake matches that of soy and fishmeal, it could fetch a similar price, Bell says. Today that's around £800 or £900 a tonne. The maggots are about 50 per cent protein and a quarter oil by weight, and Bell says the fat could easily be separated off for sale as fuel or a food additive, for example in salmon feed. The maggots also yield their structural material, chitin, which is used as a stabiliser in many pharmaceutical products and as a binder in adhesives.
The economic potential is huge, says Finney. He calculates that manure from the 280 million chickens reared every year in the US could be converted to protein, fat and chitin worth at least $660 million. The corresponding figure for pigs could be as high as $5 billion, he says.
But is meat from fish and animals fed on maggot cake likely to be safe to eat? Drew says nothing is happening that wouldn't take place harmlessly in nature. "We're all eating trout from streams, and guess what they eat?" he says. Likewise, chickens, pigs and other farm animals all eat grubs and maggots that they find while foraging. Maggot cake is just a more concentrated form.
Finney agrees. He points out that the human consumer of meat from animals fed the maggots is two stages away from the manure, digested first by the maggots and then by the animals. This contrasts with consumers of organic vegetables, who are only one stage away, as the manure directly feeds the crops.
But with the memory of BSE, commonly known as mad cow disease, still fresh in the UK, people may be wary of such recycled products. The spread of BSE was traced to the practice at the time of including bovine material in feed intended for cows, and it spread exponentially through cows eating infected brain tissue. Bell says that because of this, his project specifically excludes the use of any animal parts.
Yet although there is clearly potential in maggot food, is it likely to catch on?
Michael Formica, chief environmental counsel to the US National Pork Producers Council, says that it evaluated the technology some years ago and concluded that although practical, it was uneconomical.
But as the cost of fodder has skyrocketed since then, the economic case for maggots may now be much stronger. "We are going to go back and look at it," Formica says.
A US government panel that evaluated the technology in 2010 also came out broadly supportive. Jeff Silverstein of the US Department of Agriculture Research Service in Beltsville, Maryland, is optimistic but notes further steps are needed, such as confirming that animals will eat the stuff.
The leap from lab to market is a big one, says Michael Rust of the US NOAA fisheries service. "Still, the mega-trend is for needing more animal feed protein and fat, so I wish them well."
"We envision this as a major shift in the food supply system," says Craig Sheppard, co-developer of the black soldier fly process.
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"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
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