If you prefer your milk without the moo, a variety of plant-derived "milks" exist. While some people swap cows' milk for plant milk due to having dairy allergies, others choose to consume plant milk for environmental or animal rights reasons. These are just the type of people who might soon reach for a glass of lab-made milk instead.

Food writer Corby Kummer joined Boston Public Radio on Wednesday to explain how lab-made dairy can produce milk without the methane.

"Protein alternatives made from plants are all the rage — as we know Beyond Meat and Impossible Burgers — but it's happening in fish, eggs and milk. This milk is not an alternative — it's got all the allergens of dairy products — but what it doesn't have is belching cows behind it," he said.

As funny as it is to imagine cows belching, the methane released from these burps is no joking matter. Cow burps add up, accounting for 26 percent of all U.S. total methane emissions, according to the National Geographic. Cow-free dairy could help lower this number, said Kummer.

"The main reason behind it and most of these alternatives is the environment. It's to save the methane emission from cows," he said. "It's to save all the animals from the huge concentrated animal feed lots and all these huge operations."

Cow-free dairy swaps 1,000+ pound cows with much smaller organisms — microbes — to produce the dairy proteins instead. These proteins are what makes milk look and taste like milk, Kummer said.

"Synthesized proteins mimic the two main proteins in milk, which help coagulate cheese and help give flavor to milk. They're already being synthesized. It's very successful and works fine. Where it doesn't work yet is on any kind of big scale — that's a ways off."

Until researchers figure out how to increase productivity for a larger scale, you won't be able to find this lab-milk in your dairy aisle quite so soon. In the meantime, you're more likely to find lab-made dairy in the form of cheese, according to Kummer.

"It's going to be the base of cheese, whey protein, that lots of cheese makers make. What it does is have all the protein properties that's going to help in making cheese and probably be indistinguishable when they add the salt and the other flavoring that goes into cheese. So it's probably going to be very useful to the industry," he said.

Kummer added that even though lab-made milk will take a longer time to reach the masses, demand for it is there. "The company that's farthest along with this, called Perfect Day, did a test market in July of limited-edition batches of flavored milk, and they sold out."

Kummer is a senior editor at The Atlantic, an award-winning food writer, and a senior lecturer at the Tufts Friedman School of Nutrition and Policy.