Once it's left the cow, all that methane gas goes up into the atmosphere and makes the hole in the ozone layer bigger, making global warming worse.
Beans: probably not for cows
The cows also lose energy every time they let one go, so it's important for them as well as the environment.
Apart from the obvious - don't feed baked beans to cows - the scientists have worked out a special mixture to give the cows to make them smell sweeter.
They've been given a big pile of money to make sure it all works, and will be hoping for a pat on the back at the end of the project.
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