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Low-Burp Burger?
BURGER KING
SUSTAINABLE WHOPPER? Burger King says it’s created a “methane-reduced” version of the classic burger.
Recently, the fast-food chain Burger King added a new item to its menu: beef that’s more environmentally friendly. It comes from cows fed a special diet designed to make them less gassy.
A cow’s gut contains microbes that help break down tough plant fibers. This process, called fermentation, produces methane. Cow burps and farts are loaded with this potent greenhouse gas, which traps heat in Earth’s atmosphere, contributing to climate change.
Burger King claims that adding a plant called lemongrass to cattle feed reduces this microbial methane production by 33 percent. That’s based on a study the company conducted with scientists in Mexico. But many researchers are skeptical of Burger King’s claim. That’s because Burger King’s cows only munch on lemongrass during the last few months of their lives—up to 90 percent of methane emissions from cattle happen before that point.
COURTESY OF GREGORY URQUIAGA/UC DAVIS
BURPING BOVINES: A single cow produces between 70 and 120 kilograms of methane per year. Scientists at UC Davis, pictured left, are researching the impact of cows’ diets on methane production.
A cow’s stomach has four chambers that help the animal digest fibrous plants, like grass and grain.
SHUTTERSTOCK.COM
After a cow swallows a mouthful of grass, it enters the rumen—the stomach’s largest chamber—where microbes start to digest the food.
The partially digested food passes into another stomach chamber, the reticulum. It forms the food into a ball.
The cow spits up the ball of food, called cud, and chews it for a second time.
The rechewed food moves into the third stomach chamber, the omasum, which absorbs any water the food contains.
The cow’s final stomach chamber, the abomasum, contains stomach acid, which kills digestive microbes and further breaks down food.
The intestines absorb the meal’s nutrients.