New Zealand entrepreneurs are developing methane-free milk in labs. Olivia Wannan meets the pioneers.

This story was first published on Stuff. 

For 10,000 years, we’ve done the same thing to produce a drink of milk. Farms have cleared land to grow grass, raised cows, impregnated the animals, taken the calves aside, and milked their herds.

Over that time, consumers developed a considerable appetite for cows’ milk, which appears in everything from yoghurt and cheese to biscuits, chocolate and sports shakes.

But in the past 50 years, we’ve spotted something going very wrong with the climate, and now we’re left with limited time to avoid catastrophic consequences. And the source of dairy milk – methane-belching cows – is a significant contributor to that problem, particularly in Aotearoa.

That knowledge led dairy experts, food scientists and biologists – including a number of Kiwis – to invest in a different way to produce milk.

Instead of using a large, sentient mammal to make dairy, Matt Gibson uses microorganisms. The resulting food offers an appealing climate benefit: zero planet-heating methane being belched into the atmosphere.

New Culture – Gibson’s start-up based in San Francisco – makes animal-free mozzarella, a perfect duplicate of cow-made cheese. Partnering with the likes of Kraft Heinz, the start-up is planning to launch into US restaurants and food chains in 2023.

“I’ve been a vegan for a very long time, over 10 years now. Animal rights and sustainability was such a big passion, alongside science. This idea of making animal products without the animal really captured me,” says the University of Auckland science graduate.

Courtesy of evolution, the cells of all living creatures work in a similar way. Humans, cows, yeasts, fungi and bacteria all make proteins out of the same basic building blocks (amino acids). Critically, all use the same basic intracellular processes to assemble these in order.

DNA stores the instructions for the assembly order for each protein. Every second, within our cells, portions of the instruction guide are regularly copied and sent to tiny factories, which compile the structures.

Every cell within the cow carries the instructions for the two key proteins in milk: casein and its better-known partner, whey. But the process to create them is only activated in the cells of a cow’s udder, following pregnancy.

For decades, scientists have mapped the DNA instructions from the tiniest virus right up to the most complex mammals, including humans and bovines, Gibson says. “We know the gene sequence that produces a dairy protein.”

So the company inserted the DNA instructions to produce the dairy protein into the DNA of its microbes, transforming them into dairy-making machines.

Gibson’s New Culture isn’t the only one to have this bright idea. In the US, dairy protein manufactured by a fungus, rather than cows, is made into milk, ice cream and cream cheese.

And at home, three Kiwi women have founded Daisy Labs – and designed a couple of microbe strains to produce dairy proteins.

Irina Miller was working in the dairy industry when she learned about microbe-produced foods. “I was waiting for it to happen [here]. Then it didn’t. I thought we’d better do it ourselves.”

Miller asked University of Auckland microbiologist Nikki Freed about the potential for microbes to create dairy proteins. “I said: It’s easily feasible,” Freed says. “I laugh about that now.”

The pair then brought Massey University student Emily McIsaac on board. “We take the piece of DNA and put it inside a friendly microorganism,” she explains.

That’s easier said than done. Miller compares it to computer coding, using chemicals.

If Daisy Labs inserts the dairy recipe into the wrong place, the microbes could stop functioning properly. It’s akin to inserting a word into a full sentence. Place it at random and you’ll probably get something that makes no sense.

The dairy DNA needs to fit into the surrounding host’s DNA so that the microbe understands the recipe.

It’s also no good if the microorganism accepts the new DNA but never (or only rarely) activates it, Freed says.

“It goes about its day, replicating itself and making its normal proteins. We’ve included one extra single protein for it to make,” she says. “We want it not only to produce the protein, but a whole lot.”

Another hurdle is getting the microbe to “export” the protein from where it’s made inside the cell to outside the cellular walls, McIsaac explains. “There are loads of little tricks. It’s just which of those tricks are going to work.”

Daisy Labs could then collect a purified source of whey or casein, without having to destroy their microbes or get the hosts’ own proteins mixed up in the finished product.

They’d also have a food with a far smaller carbon footprint than the traditional methods.

In the US, Perfect Day’s fungus produces at least 90% less climate pollution than a livestock farm for the same amount of food.

Daisy Labs plans to do a similar calculation, comparing NZ-based microbes against domestic dairy farms. Miller expects “huge” environmental and animal welfare benefits.

“You don’t have to grow a big sentient animal. You don’t have to impregnate it, take her calf and cull it most of the time… It doesn’t pee or poop. It doesn’t produce methane. [Animal waste] doesn’t go into our rivers,” she says.

Gibson’s New Culture will launch with mozzarella, because cheese is a particularly polluting foodstuff, he says. One litre of dairy milk makes about 100 grams of cheese.

“Dairy cheese is usually considered the third-worst food product, after beef and lamb, for greenhouse gas emissions and land usage – and the worst for water usage.”

Recipe for success

Cow’s milk contains proteins, plus fats, cholesterol, sugars (including the allergen lactose), salt, vitamins, minerals and water. In fact, milk is about 87% water, meaning Kiwi dairy factories burn a lot of coal to dry milk into powder to ship it overseas.

But while that recipe is everything a growing calf needs, it’s not ideal for a cheese factory.

Traditionally, cheesemakers start by separating the casein protein in cows’ milk from whey, Gibson says. The whey can be used in other foods, from ice cream to protein powders.

In contrast, microbes – which can be situated right next to the factory – are programmed to just churn out the desired casein.

Then, cheesemakers return to tradition: casein is solidified into curds, with enzymes and other strains of bacteria added to shape the cheese’s taste and texture.

As anyone who’s tasted most vegan alternatives knows, cheese made without dairy protein lacks a certain something, Gibson says.

“The melt and the stretch of mozzarella, the gooeyness of camembert, the sharpness of cheddar, the crumbliness of feta – casein protein is just such a crucial ingredient to the taste experience,” he says.

New Culture’s mozzarella is indistinguishable from the cow-made version, he says. “We’ve done countless taste tests with investors, chefs and food journalists… We can’t wait to get it in front of consumers and see their reaction.”

Daisy Labs is also commonly asked about taste tests. But since whey protein “doesn’t taste like much”, Miller says, this isn’t high on the three founders’ to-do list.

Whey has “a mild, milky flavour” – but combine it with (plant-based) sugars, salts, fats and flavours and magic happens. The team are on track to produce enough whey to release a limited-edition ice cream “in the not-too-distant future”.

Science faction

The process of taking a piece of DNA from one organism and inserting it into the code of another is best known as genetic engineering.

The term has a certain fear factor in Kiwi society – and we’ve got relatively strict rules regulating labs undertaking genetic engineering and companies producing foods using the technique.

When the topic comes up, Freed quickly stresses that only the microorganisms are genetically engineered.

“None of the final product is genetically modified at all,” she says.

The proteins are indistinguishable from those coming from a dairy cow.

Eventually, billions of Daisy Labs’ microbes could live in large stainless steel vats, kept to the tiny creatures’ ideal conditions. The enclosed factory will feed in sugars and oxygen to each batch. In return, the microbes will produce a steady stream of dairy protein for a few days.

The vats will siphon off liquid containing the dairy proteins, Freed says. That will be purified, dried and supplied to yogurt, ice cream and other dairy manufacturers.

Food for thought

Chances are you’ve already eaten something grown by these mimicking microbes. Vanilla – particularly in processed foods – commonly comes from a microbe rather than from the orchids that grow the beans.

Microorganisms also produce rennet, an enzyme used in cheesemaking, Gibson says. The technique “has been used for food ingredients for decades”.

Dairy giant Fonterra invested in microbes able to make dairy proteins (but couldn’t find time to speak about it for this feature).

Daisy Labs already has plenty of interest for their product, particularly from niche food companies, Miller says. “We are blessed to have people reaching out to us asking when it’s going to be ready. I don’t know if that would happen anywhere else in the world.

Meanwhile, New Culture aims to produce “millions of pounds” of cheese annually, by 2027. Admittedly, that’s a drop in the bucket of US cheese production, Gibson says.

Still, he’s convinced microbe-produced dairy proteins will upend agriculture. The real question is when. “Will it happen in five years or 20 years?” he says.

Because microbes require less feed and land, labs will eventually produce dairy proteins more efficiently and cheaply than farms. The start-up’s mozzarella is currently more expensive, Gibson says, but scaled-up facilities will drive the costs down.

Gibson says more efficient technology always wins.

“This is going to start out as a premium niche product. But very quickly it will become the mainstream product of choice,” he adds. “We are going to disrupt an industry.”