Pea milk provides a source of protein and could be the next big thing in alternative milk. Photo / Getty Images
Research suggests pea milk emits a fraction of the planet-warming gases of cow’s milk production and is more nutritious than most other plant-based milks.
Choosing from the options in the milk aisle often involves trade-offs between health and climate. Cow milk production involves a lot of planet-warming emissions. Plant-based milk alternatives are generally better for the planet, yet they tend to lack some of the nutritional benefits of cow’s milk.
Research suggests that milk made from peas may come closest to being both healthy and sustainable. Its production emits a fraction of the planet-warming gases of cow’s milk, and it has more protein than other plant-based milks.
No, pea milk isn’t green, and it doesn’t taste like peas. (Though my Washington Post climate desk colleagues had mixed opinions on the taste and texture – more on that below.) The key ingredient is yellow split peas. After the peas are harvested and milled into flour, commercial manufacturers extract the pea protein. Then, to mimic the components of cow’s milk, they blend it with water, fat (in the form of vegetable oil) and a bit of sugar (typically cane). They also add nutrients such as calcium and vitamins. The resulting beverage has an ivory or cream colour.
A 2023 peer-reviewed study estimates that one cup of traditional cow’s milk is responsible for an average of 330g of carbon dioxide equivalent – similar to the amount of planet-warming gases emitted by driving a gas-powered car just over three-quarters of a mile. Producing that single cup of milk also guzzles about 20 litres of water, according to the paper published in Current Environmental Health Reports.
By comparison, making a cup of pea protein milk generates an average of 71g of carbon dioxide equivalent. And a 2017 life cycle analysis commissioned by Ripple, a prominent maker of pea protein milk based in California, estimated that its product’s total water use is about 86% lower than traditional dairy milk.
Pea milk is generally similar to other plant-based milks in terms of its environmental impact, said Raychel Santo, a researcher with the nonprofit World Resources Institute who worked on the 2023 paper. On average, plant-based milks generate roughly one-third or less of the greenhouse gas emissions of cow’s milk, and – with the exception of almond milk – they use considerably less water.
Dairy has a big environmental footprint in part because cows release methane, a greenhouse gas some 80 times more potent in the short term than carbon dioxide. “Finding opportunities to reduce some of those emissions within diets can have a lot of positives to reducing our overall contributions to climate change,” Santo said.
Peas can also start helping the planet from the moment they’re planted, she said.
Pea plants, like most legumes, pull nitrogen out of the air and, with the help of bacteria on their roots, deposit it underground. This fertilises the plants and allows the soil to hold more nutrients and water for the next crop, reducing the need for carbon-intensive nitrogen fertilisers. Soy plants, which are used to make soy milk, also have this nitrogen-fixing benefit, Santo said.
“Whether [legumes] are in plant-based milk alternatives or in other forms, such as just eating dry beans and lentils and peas directly, they can have a lot of benefits to the environment in addition to their relatively low greenhouse gas footprint,” she said.
Where pea milk can really stand out from most other plant-based milks is its nutritional profile.
When compared with cow’s milk, which has an average of 8.2g of protein per cup, many popular plant-based milks – including oat, almond and coconut – fall short. One cup of almond milk, for instance, has an average of 1g of protein. But soy milk averages 6.1g of protein, and pea-based milks average 7.5g, the 2023 study found.
“Legumes are high in protein, high in fibre and have a lot of nutritional benefits – those are carried into the product,” said Becky Ramsing, a senior program officer at the Johns Hopkins Centre for a Livable Future.
Other researchers are also studying the nutritional benefits of pea milk, including how the plant-based beverage stacks up against dairy in helping older adults preserve bone density.
But replacing cow’s milk with plant-based alternatives, even if the products have high protein content and are fortified with essential vitamins and minerals, can be complicated, Ramsing and other experts said.
Dairy milk provides a good portion of the protein and calcium children need to grow, said Ramsing, who also worked on the 2023 study comparing milks. Unless children can’t drink cow’s milk because of an allergy, intolerance or dietary restriction, they probably shouldn’t switch entirely to plant-based milks, she said.
Adults, who can usually get protein and calcium from other sources, have more flexibility with their milk choices, she said.
“If you’re an adult, it’s beneficial to look into some alternatives to dairy,” she said. “I would choose the alternatives that are legume-based, like soy and pea protein milk. … We can have moderate dairy in our diet, but we can’t ignore the environmental and public health impacts of how we produce animals for food.”
Of course, aside from environmental and health impacts, people often factor cost, taste and dietary restrictions into their milk decisions.
Plant-based milks can be more expensive than traditional cow’s milk. They also vary in taste and creaminess.
In a small taste test of Ripple pea milk, Post climate staffers said they were struck by the “chalky” texture. While they appreciated that it didn’t taste like peas, some described the flavour as “neutral,” others as “bland”.
One person who added it to hot black coffee noticed that it started to separate, while another said that it left a film in the bottom of their cup. A few people said it reminded them of health shakes, with one concluding that it “felt too gym-bro”.
Those reviews weren’t bad, considering that everyone’s initial reaction to the mention of pea milk was a look of disgust.
“The name pea milk just doesn’t come across very well,” Ramsing said.
Pea milk makers may be aware of this. “Pea milk” isn’t emblazoned on packaging the way manufacturers proclaim “oat milk” and “almond milk”. More often, it appears to be advertised as plant-based milk, with a secondary mention of “pea protein”. There is no brand equivalent of Oatly or Almond Breeze.
A Ripple representative, though, cited a lack of awareness among consumers to explain why pea milk hasn’t taken off as much as oat, almond or soy.
“Ripple milk is still unknown to so many milk drinkers - dairy and non dairy alike,” a spokesperson for the brand said.
Although the market for milk alternatives is growing, it is dominated by almond, oat, soy and coconut, according to data from NielsenIQ. Pea milk accounts for only a sliver of plant-based milks sold, according to NielsenIQ, and it’s not as widely available as other options.
“I would definitely drink more pea protein milk if I could find it,” Ramsing said.
The show blends te reo Māori with stunning circus theatre.