There’s a farm in England that now markets its milk as “climate-smart”, but what does that really mean? Apparently, Brades Farm, is one the first to begin feeding its cattle a new supplement that shrinks the amount of methane, a potent greenhouse gas, that cows emit when they belch, thus making the milk “climate-smart.” And while this may seem a bit bogus, the Swiss company behind the new supplement, will soon be issued the world’s first carbon credits for methane reduction in cows

Cow burps are a big part of the reason that beef, cheese, and ice cream have large carbon footprints, and Mootral wants to help the industry transform. Methane is 84 times as potent a greenhouse gas as carbon dioxide. A single industrially farmed cow produces roughly as much pollution as six average European cars; there are around 1.4 billion cattle in the world. By one estimate, cows emit more climate pollution globally than the entire economies of Japan or Germany.

The company’s product adds compounds from garlic and citrus to pellets that are mixed in with cow feed. The startup grew out of a previous company that researched the antimicrobial effects of garlic in human diets and then discovered that garlic also benefitted cows. Inside a cow’s stomach, microbes typically break down food and produce methane. The garlic-based supplement can help reduce the number of microbes so burps become less potent.

It’s a challenging product to develop. The mix has to be right, so that it has no detrimental effect on the milk, meat, or the animal itself. In peer-reviewed studies, the product has been a success, reducing emissions from belches by 30% without adverse effects. (In one test on Brades Farm, which has been using the supplements for the last 12 months, emissions dropped as much as 38%.) 

Widespread adoption is the next challenge for Mootral, but it believes that to be possible by shopping its product around to large dairy companies or restaurants that want to cut emissions. Mootral says supplying the supplement to one cow for an entire year will cost around $55 a year, but that price doesn’t just lead to lesser emissions; according to studies so far, dairy cattle that eat the product make an average of 4% more milk, so for dairy farms, the investment can pay back over time.