University of Pennsylvania researchers turn food scraps into building materials

Researchers at Penn in Philadelphia are using food scraps to build the future of sustainable architecture and engineering. 

The pioneering project at the University of Pennsylvania Stuart Weitzman School of Design is working to create environmentally friendly alternatives to concrete and epoxy while also reducing the waste going into landfills. 

First, stalks and vines are collected from the university's farm on campus. Penn Farm program coordinator Ezra Tischler gathers inedible fibrous and woody materials from plants for the project.

"Okra was one of the crops used in the project," Tischler said. "It kind of opened my eyes on ways we could expand sustainability efforts. We are always looking to decrease food waste."

Then, it's off to one of the school's dining halls where senior researcher Yasaman Amirzehni picks up a container filled to the brim with pineapple and melon scraps cut by executive chef Mouhamed Mboup.

"Being able to have a partner that turns food scraps into building materials, I think that's something that's really great," Mboup said. 

Each day, about 15,000 meals are made in dining halls at Penn. More than 90% of the food waste from those meals is composted, and the rest is collected and given to the school's DumoLab, which is led by director Laia Mogas-Soldevila.

The food scraps and stalks are brought to the lab where they're dried, ground up and mixed with various natural binders and fillers leading to a compostable alternative to cement or epoxies.     

"Can the building environment be made out of stuff that nourishes the planet instead of depleting it at the end of its life?" Morgas-Soldevila said.

Her team of researchers and students has been on a two-year mission to reimagine our spaces.

"What we do at DumoLab is what architectures can be proposed with only natural materials and natural binders," Morgas-Soldevila said. "So, can we build without pouring cement and epoxies and formaldehydes? Instead, use binders in nature that can assemble natural materials into a future where Earth can digest the architectural realm."    

This isn't about making skyscrapers necessarily. 

These biodegradable materials can be used to make shingles, shaded areas, pavers and even furniture parts. It's all repurposed to serve an environmental purpose.

"This is the pH-sensitive pieces that we can put into the soil and when there's acidic rain, they will change color to pink," senior researcher Yasaman Amirzehni said. "So, you know your soil is not healthy."

The compostable materials have been tested against the elements.

"We are quite successful," Morgas-Soldevila said. "We've been able to check the accelerated weathering of many of our samples. And we see that in 50 years, depending on what we do with these biopolymer systems prevail. They only change color or only change patina."

The researchers are using the Earth's tools to build structures that bring us closer to life.

"My goal would be to see if we can change the unhealthy materials to these materials and get back the soul and the colors and the feelings and like the soul of the buildings, instead of using concrete," Yasaman Amirzehni said.