FEEDING THE 10 BILLION

Tomorrow’s menu. To feed billions more mouths, we will have to acquire new tech and tastes.

In 1970,US biologist Norman Borlaug won the Nobel peace prize.Dubbed the father of the green revolution, Borlaug was credited with saving over a billion people from starvation. That figure maybe a guesstimate, but there’s no doubting the success of the green revolution: in 25 years, it more than doubled cereal production in many parts of the world through the use of high-yielding varieties and modern farming technology.

Today, the human population is almost twice what it was then, and in 2050 it could reach 10 billion. Even now, some 800 million people go hungry. Feeding ourselves without desecrating the planet is one of the biggest challenges we face. We are running out of land, water and time. To make matters worse, as the world warms, agriculture will get harder.

Feeding the 10 billion will require some creative solutions – and unpalatable compromises. Perhaps we can learn to love algae, corn husks and crickets, butwhat about lab-grown meat, synthetic milk and genetic modification? How far are we prepared to go to kick-start green revolution 2.0?

It’s not that the original green revolution has nothing left to give. It relied on mechanised farming, modern fertilisers, effective irrigation and better seeds to increase productivity. New technology can make existing methods more effective,while also extending the benefits to parts of the world that didn’t gain so much from the original green revolution.

That’s Africa above all. “By 2050, the world will need to boost agricultural production by at least 70 per cent. Nowhere else is the potential to achieve this increase as great as it is in Africa,” says Agnes Kalibata, president of the nonprofit Alliance for a Green Revolution in Africa. Around half of the world’s unused agricultural land – 4.5 million square kilometres – is in that continent. What’s more, yields from cultivated land there are much lower than in Europe or North America.

A 2013 report from the World Bank concluded that there is potential to triple the worth of Africa’s agricultural output to $1 trillion a year by 2030. Traditional green-revolution approaches will play a big part, especially in sub-Saharan Africa, where two-thirds of the power used to prepare land for farming is still provided by human muscle. But according to a report by consultancy McKinsey, digital technology could provide an additional boost of $3 billion per year. In Kenya, for example, a smartphone app called iCow helps dairy farmers keep milk records, receive tips on nutrition and contact local vets. Farmers with smartphones can also benefit from satellite data providing information such as which crops need more water or fertilisers.

These types of technology underpin so-called precision agriculture – applying the optimal amount of inputs such as water, fertiliser, pesticides and labour, at the right location and time. It’s an approach that can help boost yields in theWest, too.“The longterm goal is to increase the level of detail in crop management to the point of single-plant management,”says Alex Thomasson at Texas A & M University in College Station. Imagine tractors with infrared cameras that can measure where exactly fertilisers are needed, and drones with thermal sensors hovering over fields, collecting data on plant irrigation (those short onwater appear cooler in an image).“Production optimisation can offer a great deal of help in feeding the world, and water may well be the most important aspect,” says Thomasson.

It also allows us to farm inways and places not considered feasible before. In some cities, vertical farms are taking over roof tops and abandoned buildings. They can be highly efficient, with yields up to 130 times those on an equivalent area of arable land, according to AeroFarms, one of the firms building on the concept. In Montreal, Canada, for example, a 2900-square-metre rooftop greenhouse feeds some 2000 people.

As well as using 95 per cent less water than conventional cultivation, it benefits from the fact that night-time temperatures tend to be higher in urban areas than in the countryside, lowering heating costs.“Outdoors you can control nothing, indoors you can control everything,”says Dickson Despommier at Columbia University in NewYork City. In Africa, that could also mean keeping crops safe from things like locusts or even civil unrest. What’s more, urban farms are close to their customers, limiting the risk of crops spoiling in transit.

But further increases in productivity and extending the range of agriculture are not going to feed the 10 billion on their own. That’s going to require a fundamental rethink of what we eat.

There are some 50,000 edible plants, yet just three –wheat, rice and maize – account for over 60 per cent of the world’s calorie intake. Indigenous plants better suited to local conditions could offer better solutions. In Africa, these include bambara, which produces a nutritious bean and is resilient to hot and dry conditions, and marama, with its nutty-tasting seeds, protein-rich tubers and ability to thrive in the poorest of soils.

Anyone for algae?

People are also starting to recognise the nutritional potential of algae, including seaweed. Some types,when dried, contain 70per cent protein; others are packed with essential fatty acids. Seaweeds are abundant in micronutrients, too, from iron and zinc to potassiumand calcium. There are more than 100,000 species of algae, yet we currently cultivate just 20, so there’s plenty of scope for expansion.A big advantage of algae is that its cultivation doesn’t require agricultural land: it can be done offshore or in places where the ground water is salty, even in the Sahara.

Other technological fixes are likely to put even stranger items on future menus. For example, Percival Zhang at Virginia Tech in Blacksburg and his colleagues have found an efficient way to turn cellulose into starch using genetically modified E. coli bacteria. This could be used to make food out of fibrous plant materials such as corn husks and even perennial grasses.

That may sound drastic, but ifwe are to feed 10 billion people,we have no option but to eat more plants and less meat. Currently, a third of Earth’s arable land is used to grow feed for livestock. If everyone ate a US-style diet, by 2050 we would need around 4.5 times as much meat as we produce now. There simply isn’t enough land to do that.

One way to fill that gap is to eat more of what 2 billion people across the globe already do: insects. It takes 25 kilograms of feed to produce 1 kg of beef, but just 2 kg to get 1 kg of crickets. Insects contain all the essential amino acids we need, and some, including termites, grasshoppers and caterpillars, are better sources of protein than beef or chicken.

But insects have an image problem. It’s not simply that the uninitiated find them off putting; consumption is actually decreasing among those who traditionally eat them. “They feel that they need to eat meat to adopt a prosperous lifestyle, like people in the West,” says Marcel Dicke at Wageningen University, the Netherlands. One way around this, he believes, is for insects to become part of an affluent Western diet.

An alternative is more plant-based meat substitutes. First there was tofu, then “textured vegetable protein”, and now we have “high moisture meat analogues”. These mockmeats are made by breaking and reassembling plant derived protein molecules in extruders – the same machines used to produce breakfast cereals and spaghetti. Already there are dozens of them on the market, from sausages made from lupin beans to the Impossible Burger,which takes meat mimicry to a new level using a plant-derived version of haem, a component of the blood protein haemoglobin, to create a veggie burger that bleeds.

Then there’s “clean”meat grown from muscle tissue in labs, or “carneries”,which also has big environmental advantages over conventional meat. Four years since we saw the first lab-grown burger (cost: $330,000), the technology is gathering pace. Last year, an Israeli start-up announced that it is developing clean chicken. Meanwhile, a US company has already done tastings of “steak chips”– a cross between a potato chip and beef jerky – and says they could be on supermarket shelves within a few years.

How clean meat will go down with consumers remains to be seen. But according to Anon van Essen at Maastricht University in the Netherlands,who worked on the first clean burger, there is “nothing to fear”.“These cells are dead, as in any meat. Stem cells are everywhere: in your muscles, in your regular food,” he says.

Even before we are eating lab-grown meat, we could be consuming cow-free milk and chicken-free eggs. Such products are possible thanks to synthetic-biology technologies that genetically modify yeast to “brew” animal proteins. Again, there are environmental advantages over conventional production methods. Yeast-made milk uses 98 per cent less water and requires up to 91 per cent less land than a cow’s milk. Synthetic products can be healthier, too: it’s possible to make milk without lactose, for example.

Some consumers may see these products as “unnatural”, but companies developing them liken their process to making beer. They also point out that the GM yeast doesn’tmake it into the end product. And if we are to meet the global food demands of 2050, some of us may have to overcome our aversion to genetic modification. GM can create crop varieties that are resistant to disease, drought and other environmental hazards that are becoming more prevalent as a result of climate change. It also has the potential to increase the overall amount of arable land by, for example, giving us crops that can thrive in salty or alkaline soils. And it could produce plants that are more efficient. For example, Australian researchers recently discovered an enzyme found in common panic grasses that if engineered into cereal crops could significantly increasing yields bymaking them better at taking up carbon dioxide for photosynthesis.

“It’s easy to make GM crops sound scary, but there is really no basis to the claim that they are genetically any less safe than conventionally bred ones,” says plant geneticist Ottoline Leyser at the University of Cambridge. Rather than worry about the technology itself, she says,we need to consider the consequences of particular traits introduced into plants, such as herbicide tolerance.

There’s no doubt that feeding 10 billion people will require far-reaching changes both in what we eat and how we think about food. “With a problem as complex as food security, the idea that you should dismiss anything that can contribute to solving it is inappropriate,” says Leyser. “We have an extensive toolbox to address food security and we need to make sure we pick the right tools for the right job, at the right time.”

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WASTE NOT, WANT NOT

Around a third of all our food ends up rotting on farms and in landfills. That could easily provide sustenance for the 800 million people who currently go hungry, with plenty spare to help feed a growing human population. Reducing waste is the “most important component” of feeding the world of the future, according to John Floros, dean of Kansas State University’s College of Agriculture.

In the West, most food loss occurs late in the supply chain. UK households waste 20 per cent of groceries simply because of confusion over labels, throwing out items based on “best before” dates, for example. “Such food is still good afterwards. Maybe it will have a few less vitamins, but you can still eat it,” says Floros.

One way forward is to raise awareness. Better labelling can help too – introducing “freeze by” dates, or even banning best-before dates, as France did with its equivalent in 2015. Another option is to convince consumers to buy imperfect-looking produce. Some supermarkets are already on to this, encouraged by the Ugly Fruit and Veg Campaign and others.

Going even further, a store called Wefood in Copenhagen, Denmark, sells only groceries that would otherwise end up in the dump. Even restaurants are starting to use waste food. They include Freegan Pony in Paris, France, which serves vegan food made from produce recovered from local markets.

In the developing world, most food loss happens long before goods reach consumers, mainly because of shortcomings in infrastructure, processing, storage and refrigeration. No one strategy will combat these, and investment is lacking. However, in Nigeria, for example, a company called ColdHubs is building solar-powered “cold stations” to store produce close to farms and markets.

Food preservation is another solution, and not just in developing countries. Here, there are promising developments, such as sterilising foods using high pressure, short electric pulses or blue LEDs. “In Western countries, the popular position is that all processing is bad,” says Floros. “We have to change that perception.”

Written by Marta Zaraska in "New Scientist", USA, issue 3118, March 25-31, 2017, excerpts pp.32-35. Adapted and illustrated to be posted by Leopoldo Costa.