Protein is essential for a healthy diet. And you can get your protein from plants and animals — beans, peas, nuts and wholegrain seeds, and fish, poultry and other livestock.

Nutrition experts at the Harvard School of Public Health advise you take most of your proteins from plant-based sources. Red meats, such as beef, they say, "should be consumed on a more limited basis."

Meat production is, for one, considered environmentally unsustainable. But too much meat can also lead to health problems, including bowel cancer. Often, it's more a case of the way the meat is cooked than the meat itself, but still it is worth bearing in mind: You are what you eat, as the saying goes.

But many people enjoy eating meat. So the idea of lacing rice — a plant-based protein — with sustainable, lab-grown beef should be welcome news. That's what scientists in South Korea say they have created, and they are calling it "beef rice".

What is beef rice?

Researchers in Seoul, South Korea, took meat and fat cells from cows, coated with fish gelatin, and inserted them into rice grains, where they grew. 

The gelatin coating helped nutrients from the animal material — beef muscle and fat stem cells — to grow and enrich the rice.

It was grown in a culture for around 10 days, allowing the protein and fat from the animal cells to develop. And what resulted was a pink-white grain.

But does it taste good?

"The initial flavor is predominantly that of rice. However, there are multiple complex flavors intertwined. It had a somewhat chalky but nutty protein flavor, followed by a slightly creamy, buttery aftertaste," said Jinkee Hong, a lead author of the study into beef rice at Yonsei University.

How nutritious is beef rice?

Hong said his beef rice contained 8% more protein and 7% more fat than conventional rice. That would make it a rich source of essential amino acids, which produce proteins.

"Th[is] demonstrate[s] its potential as a future superfood but also offer[s] ideas for the development of new forms of hybrid food products," said Hong.

But some food experts have questioned the nutritional value of Hong's beef rice.

"The end product contains 4.8 grams (0.17 ounces) of cultivated bovine cells per 1 kg (35 oz) of rice. This means that 0.5% of the end product is cultivated meat and 99.5% is rice. For replacing meat, the percentage of the protein in the final product would need to be higher," said Hannah Tuomisto, a professor of sustainable food systems at the University of Helsinki in Finland.

Beef rice is only one of several experiments to modify rice with the goal of getting more nutrients into people's staple diets.

Golden rice, for example, is genetically engineered to contain a form of vitamin A, which was found to be lacking in some people's diets in parts of Asia and Africa.

How 'green' is beef rice?

Hong and his team said that cultivating their hybrid rice would produce fewer greenhouse gases than producing conventional beef protein. 

They say 100g of beef protein production releases about 50kg of carbon dioxide (a number substantiated by previous studies), while producing 100g of protein from hybrid rice would release less than 6.27kg of carbon dioxide.

"Cultivated meat is an extremely promising field due to its potential benefits for the environment, food security, sustainability and animal ethics," said Hong.

The team are not the first to work on lab-grown meat products, either. The first lab-grown meat burger was unveiled in 2013 by Dutch scientist Mark Post.

Less than a decade later, the lab-meat industry had grown to more than 150 companies worldwide. Most companies have focused on producing alternatives for common meats, such as pork, beef, and chicken.

Why is it so hard to buy lab-grown meat?

Hong said lab-grown meat is still too expensive for mass production and that means it's been tough to get it onto supermarket shelves.  

One of the main challenges is that lab-grown meat relies on animal products to grow the cells. In Hong's study, the researchers obtained their initial batches of muscle and fat cells from cattle slaughtered at a local abattoir.

"All lab-based meats rely on bovine serum, the blood of a cow, as a growth supplement. It's the best way we have to grow such a quantity of cells that you can make something with. But it brings in ecological arguments, issues of animal cruelty, and it's expensive," said Alfredo Franco-Obregon at the National University of Singapore. Franco-Obregon has also worked on lab-grown meat.

But producers also have some way to go to convince people to eat lab-grown, cultivated meats.

A UK-based survey by the Food Standards Agency found only a third of participants were willing to try lab-grown meat.

Almost half the participants reported that nothing could encourage them to try lab grown meat, but more than a quarter said they could be persuaded if they knew it was safe to eat.

Edited by: Zulfikar Abbany

Sources:

Rice grains integrated with animal cells: A shortcut to a sustainable food system. Published in the journal Matter by Sohyeon Park, Jinkee Hong, et al., 2024: https://doi.org/10.1016/j.matt.2024.01.015

Protein in The Nutrition Source by Harvard School of Public Health: https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/protein/

Greenhouse gas emissions per 100 grams of protein, Our World in Data: https://ourworldindata.org/grapher/ghg-per-protein-poore