Milking Cow Cells in a Lab for Animal-Free Dairy

In a lab in Boston, a startup has spent the last few months cultivating mammary cells from a cow—and recently succeeded in finding the perfect conditions to get those cells to produce real cow milk without an animal.  “We spend a lot of time trying to understand how the biology works in a cow, and then trying to do that,” says Sohail Gupta, CEO and cofounder of the startup, called Brown Foods, which makes a product that it calls UnReal Milk.

The startup, which operates in India and the U.S., just completed a stint at the tech accelerator Y Combinator. Alternative-dairy sales keep growing: In 2020, according to the most recent data available, sales of oat, soy, almond, and other alt-milk products made up 15% of all milk sales in the U.S., a 27% growth over the previous two years. But Brown Foods, like others in the space, recognized that plant-based milk still can’t replicate traditional dairy.

They’re not yet there in terms of taste and texture,” Gupta says. They also often have less protein and other nutrients. He argues that other new milk alternatives, including those that use precision fermentation to make animal-free dairy proteins, also can’t perfectly match dairy since they still use plant ingredients for fat and other components. There are multiple reasons to move away from traditional dairy, including the fact that cows raised for milk and meat are responsible for around 30% of the world’s emissions of methane,a potent greenhouse gas. But Gupta thinks that it makes sense to stay as close to the natural process as possible. Mammary cells “have evolved naturally over centuries to produce milk in mammals,” he says. “So these cells have the entire genetic architecture to produce the fats, the carbs, the proteins.

The company’s biochemical engineers have been studying how the cells behave, what they need nutritionally to survive, and what triggers lactation. “We’re trying to emulate nature and understand what kind of chemical signals are released in a mammal to trigger the cells to lactate and start secreting milk and get into the lactation phase,” he says. Now that they’ve shown that it can work at the small scale in the lab, they’re beginning to prepare for commercial production in larger bioreactors. The company believes that it can eventually reach price parity with conventional milk. In early calculations, it says that it could cut the greenhouse gas emissions from milk by 90%. (Unlike lab-grown meat, which requires an energy-intensive process of growing cells, producing milk just requires keeping cells alive, and has a far smaller footprint.)


How To Recycle Greenhouse Gases into Fuel and Hydrogen

Scientists have taken a major step toward a circular carbon economy by developing a long-lasting, economical catalyst that recycles greenhouse gases into ingredients that can be used in fuel, hydrogen gas, and other chemicals. The results could be revolutionary in the effort to reverse global warming, according to the researchers. The study was published in Science.

Newly developed catalyst that recycles greenhouse gases into ingredients that can be used in fuel, hydrogen gas and other chemicals

We set out to develop an effective catalyst that can convert large amounts of the greenhouse gases carbon dioxide and methane without failure,” said Cafer T. Yavuz, paper author and associate professor of chemical and biomolecular engineering and of chemistry at KAIST (Korea).

The catalyst, made from inexpensive and abundant nickel, magnesium, and molybdenum, initiates and speeds up the rate of reaction that converts carbon dioxide and methane into hydrogen gas. It can work efficiently for more than a month.

This conversion is called ‘dry reforming’, where harmful gases, such as carbon dioxide, are processed to produce more useful chemicals that could be refined for use in fuel, plastics, or even pharmaceuticals. It is an effective process, but it previously required rare and expensive metals such as platinum and rhodium to induce a brief and inefficient chemical reaction.

Other researchers had previously proposed nickel as a more economical solution, but carbon byproducts would build up and the surface nanoparticles would bind together on the cheaper metal, fundamentally changing the composition and geometry of the catalyst and rendering it useless.

The difficulty arises from the lack of control on scores of active sites over the bulky catalysts surfaces because any refinement procedures attempted also change the nature of the catalyst itself,” Yavuz said.

The researchers produced nickel-molybdenum nanoparticles under a reductive environment in the presence of a single crystalline magnesium oxide. As the ingredients were heated under reactive gas, the nanoparticles moved on the pristine crystal surface seeking anchoring points. The resulting activated catalyst sealed its own high-energy active sites and permanently fixed the location of the nanoparticles — meaning that the nickel-based catalyst will not have a carbon build up, nor will the surface particles bind to one another.

It took us almost a year to understand the underlying mechanism,” said first author Youngdong Song, a graduate student in the Department of Chemical and Biomolecular Engineering at KAIST. “Once we studied all the chemical events in detail, we were shocked.”

The researchers dubbed the catalyst Nanocatalysts on Single Crystal Edges (NOSCE). The magnesium-oxide nanopowder comes from a finely structured form of magnesium oxide, where the molecules bind continuously to the edge. There are no breaks or defects in the surface, allowing for uniform and predictable reactions.

Our study solves a number of challenges the catalyst community faces,” Yavuz said. “We believe the NOSCE mechanism will improve other inefficient catalytic reactions and provide even further savings of greenhouse gas emissions.