It's pretty nasty. It wasn't a worm, but it may actually be mold according to Kraft foods, the company that makes the popular drinks.
A boy, named Aldo discovered the substance stuck in the straw of a Capri Sun. He showed his brother's girlfriend who had seen a picture on Facebook and read about a similar story a few weeks back.
"It was like slimy and like whitish, like pink. It was just like, it was gross," Ashley Hibbard said. She immediately posted a picture of the slimy substance on her Facebook page. It's now been viewed nearly 250,000 times.
Kraft says this is a rare problem, claiming mold can grow inside the pouches if they've been punctured because Capri Sun drinks don't contain artificial preservatives.
Kraft says it has spent more than $2 million to make the pouches stronger. It recommends that people inspect all pouches for holes before drinking.