When Prof Mark Post unveiled the world’s first lab-grown hamburger four years ago, he garnered headlines around the world.

Some found it yucky, others thought it was an inevitable step in the march of technology. Everyone found it interesting.

Prof Post’s argument is that conventional farming of cows is inefficient and it is a problem for the environment - not only in the amount of land that cows need to grow up, but in the greenhouse gases they belch out as they digest their food.

This problem will only get worse, he says, as growing populations want access to more meat in places such as China or rapidly-developing countries in Africa.

The Earth cannot cope with that demand and remain intact.

So, at his lab in Maastricht University, Prof Post’s team want nothing less than to revolutionise our meat.

How does the process work?

Their raw materials are just a few chunks of muscle from cows.

They harvest stem cells from the tissue and multiply them up in the lab until they have enough to turn into muscle fibres.

The muscle fibres get bound together and turned into something that looks (and presumably tastes) like minced beef.

Since 2013, the team’s process for making the meat has become more refined - the scientists have simplified the growth medium for the cells and they have also started growing fat cells to mix into the final hamburgers they make.

Fat is where a lot of the flavour and moistness of meat comes from, so it is important for the texture and quality of any consumer product.

Prof Post now wants to scale up production and spin his work off into a company, MosaMeat, that can produce the meat on a large scale.

That has its own challenges - he’ll need huge bioreactors (essentially large brewing kettles) that can grow billions of cells, rather than the petri dishes and flasks where he grows millions of cells.

And the process will need to be become automated, to prevent human hands contaminating the cultured meat.

The technology to do all this exists already, but perfecting it to grow meat will not be straightforward.

Professor Post plans to scale up production of the cultured meat. Credit: ITV News

"We now have an investor lined up from the food industry," says Prof Post.

"We estimate it will take 3-4 years to get hamburgers to the market, that will still be small-scale at £10-11 for a hamburger.

"In the years after that, price will come down and it will hit the supermarkets around 7 years from now."

There’s clearly a long way to go - the tiny lab-grown burgers the Maastricht team showed ITV News (which were just couple of centimetres across) each cost around £10,000 to make.

Could consumers face a choice between lab-grown and traditional steaks. Credit: ITV News

Even if the team can scale up their project and start selling lab-grown burgers or (in the future, lab-grown steaks), Prof Post knows that public acceptance may take a long time to get around to the idea of eating meat that does not come from animals.

But he is adamant that that acceptance will come - eventually - for environmental and animal-welfare reasons.

“Imagine a future 30 years from now and you have two identical products - one is made in a cow and has animal welfare issues as you have to slaughter the cow.

"[The other] is exactly the same, same price or lower and has no greenhouse gas emissions and no animal slaughtered. What will you choose? I cannot imagine a future where those two can co-exist. I cannot imagine it.”

It won’t happen straight away. But lab-grown meat is on its way to our plates.