The espresso machine sputters behind the counter at Crumble Coffee and Bakery in Swain Plaza. With each latte, cappuccino and espresso drink, barista Audrey Goodpaster knocks another puck of damp grounds into the trash.
By the end of a shift, the discarded grounds weigh down garbage bags hauled to the shop’s dumpster.
“I wish we didn’t throw them away,” Goodpaster said. “But we don’t really have another system.”
The shop goes through at least one 5-pound bag of espresso beans every day, often more during Indiana University semesters. Each drink leaves behind another pile of grounds destined for the landfill.
Except on Saturdays.
Instead of dumping the grounds into the trash, baristas empty them into a 3-gallon bucket tucked behind the counter. Before closing, an eighth-grader arrives to collect them for repurposing into food for mushrooms.
In the basement of her family’s Bloomington home, Gloria Chi twists a light brown oyster mushroom from the side of a 5-gallon Home Depot bucket. Under the lid, layers of coffee grounds and straw are coated in thick white mycelium, the root-like structure that forms the main body of the fungus.
A single hanging lightbulb illuminates 10 buckets huddled on the basement floor. Pink, blue and pearl oyster mushrooms sprout from holes drilled into the plastic sides by the middle-schooler.
“There was plastic in my hair for a long time,” Chi said.
Some mushrooms are only a few inches wide. Others stretch more than a foot across after nearly a month of growth.
Chi, an eighth-grader at Jackson Creek Middle School, collects used coffee grounds from nearly a dozen Bloomington coffee shops through her nonprofit, Fungi For Future. Her partners include Starbucks, Soma Coffee House & Juice Bar, Crumble Coffee and Bakery, The Inkwell Bakery & Cafe, Hopscotch Coffee and the Bloomington Bagel Company.
The 14-year-old has been working on the project since early March. She said the collection process for the coffee grounds has not always been easy.
“Somebody gave me a big bowl of water one time,” Chi said. “And it was not so good.”
Chi moved to Bloomington from Pennsylvania in July 2025. Before mushrooms, she experimented with growing tropical fruit trees.
“It was, like, really hard because, like, it was cold, and for tropical fruit trees, you need to be warm,” she said. “It was sort of like a failed project.”
By September, she had shifted her attention to fungi after researching mushroom cultivation online.
“I actually didn’t know how mushrooms grew until now because they don't like seeds or roots or anything,” Chi said. “I thought it'd be an interesting science project.”
She started with a mushroom growing kit to understand the basics. Once those mushrooms died, she wanted to do the real thing. So, she ordered mushroom spawn online and began packing buckets with layers of coffee grounds and straw.
“I like growing stuff,” Chi said. “It’s fun to try new things.”
Oyster mushrooms survive by breaking down and digesting dead organic matter.
As mycelium spreads through Chi’s buckets, it breaks down complex compounds in the grounds. Indiana University biology professor Richard Phillips said fungi are suited for that role because they are decomposers.
“Fungi produce extracellular enzymes,” Phillips said. “These are enzymes that release out into the soil and are involved in decomposition.”
As the fungi decompose Chi’s coffee grounds, nutrients like nitrogen, phosphorus and potassium become more bioavailable, meaning plants can absorb them more easily later when the leftover material is used as compost.
After harvesting the mushrooms, Chi plans to donate the remaining mixture of grounds, straw and mycelium to local orchards and local composters.
“There’s this thing called mycoremediation, where basically the mushrooms can cleanse out the toxic stuff,” Chi said. “It should be a pretty good fertilizer.”
Currently, more than 122 pounds of coffee grounds are being repurposed inside her family’s basement.
Phillips said fungi are increasingly being explored for environmental uses, from decomposition to soil restoration.
“Fungi are not so intimidating,” Phillips said. “They are mysterious, and I think that's why we're curious about them, but they can be a big part of a lot of our environmental solutions.”
Originally, Chi hoped the mushrooms could become a sustainable food source.
“I'm not growing as many mushrooms as I thought I would,” she said. “I was really hoping I could solve hunger with my mushrooms.”
She has not given up on that goal and plans to donate the mushrooms to Hoosier Hills Food Bank.
The project has become bigger than food production. It is now about reducing food waste and helping the environment.
Phillips said projects like Chi’s could grow beyond one basement operation.
“It sounds like the kind of project that could probably scale up very well, if it's something that a lot of people got interested and involved in,” Phillips said. “That could definitely have an impact on reducing food waste.”
Chi doesn’t plan on stopping anytime soon. She has received $1,500 in grants, continues to apply for more and is working to collaborate with food resource organizations around Bloomington.
“I am looking into some help from the community,” Chi said. “I hope I can do this forever but I can’t do all this work by myself.”
