Genetically engineered yeast can replace milk and eggs

One of the many real things that no politician can say to the electorate is: “You should eat less meat.” Interfering with what people eat is always politically dangerous; but the British – once proudly nicknamed Les Rosbifs – are particularly irascible defenders of our right to animal flesh.

Therefore, at COP29 this week, Keir Starmer didn’t talk about meat not at all. The Prime Minister pledged to make further significant cuts in Britain’s greenhouse gas emissions – a feat that the Climate Change Committee says will only be possible if we reduce our meat consumption. But Starmer insisted this could be done without “telling people how to live their lives”. And maybe that’s possible too.

The reason meat is so harmful to the environment is that it is a woefully inefficient food source. It means that one type of food (plants) is passed to an animal to produce another type of food (meat, dairy or eggs). Overall, for every 100 calories you put into a livestock animal, you get 17 calories out.

This means that – in addition to producing around 20 percent of global greenhouse gas emissions, largely in the form of methane burps – livestock farming takes up a hugely disproportionate share of the Earth’s resources. It uses 80 percent of the world’s agricultural land and 30 percent of all the planet’s fresh water. It pollutes rivers, exposes wild habitats and drives many of our most beloved wild species to extinction.

It goes without saying that the less meat and dairy you eat, the lighter your carbon footprint. Personal responsibility is a wonderful thing. But the consumer is not the only driver of change; more often than not, consumers even respond to technological changes that take place behind the scenes. Fifty years ago, for example, the British ate four times more beef than chicken. But with the invention of factory farming, chickens became much cheaper to raise than cows. So now the British eat twice as much chicken as beef.

The global food system is like a giant vending machine: we only see what’s on the illuminated shelves, and none of the complex machines whirring away in the back. For example, when you hear the word “dairy,” you probably visualize a bottle of fresh milk ready for your breakfast cereal. But 50 percent of the global dairy trade consists of milk powder. Most of it is used in the production of processed foods, such as confectionery, ready meals, sausages and even chips.

Similarly, about 20 percent of global egg production goes toward making processed foods. And while the world processes about 350 million tons of animal carcasses every year, only 40 to 50 percent of it is consumed as fresh meat for cooking at home: the Sunday roast of our nostalgic imagination. The other half is used for packaged snacks, ready-made meals, catering and animal feed.

In other words, a large portion of the animals we raise for food (often in unspeakably cruel conditions) end up as cheap snacks. But here’s the good news: Technology may soon be able to solve this. It is now possible to genetically engineer yeast to grow into any form of protein cell. Companies in Israel, the US and Canada use precision fermentation to conjure up, literally from scratch, milk and egg powder that is indistinguishable from the real thing and perfect for production.

The consumer doesn’t care, as long as the end product is cheap and tasty. And real meat can be saved for special occasions – just as it was for every previous generation.

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