The magic of turning food waste into paint pigments

For Yoon Jung Choi, designing changes in human behavior has led to turning food waste into works of art.

“I always wanted to rethink my job roles in the packaging industry and do my own thing, but I often wondered what I could do to impact society positively,” said Choi, assistant professor in Virginia Tech’s College of Architecture, Arts, and Design.

In 2023, Choi launched Food Magic, which utilizes a multistream recycling approach to capture food waste that can be transformed into natural powder pigments for art. According to Grist.org, the U.S. Department of Agriculture’s National School Lunch Program alone wastes approximately $5 million worth of edible food daily.

Choi explained this process, as well as the issue of food waste in public schools in America, in a paper she presented at the Design Research Society’s conference on June 27.

Funded by the Institute for Creativity, Arts, and Technology (ICAT), Food Magic successfully engaged local school and community groups in the New River Valley to help co-design this potential systemic transformation toward a circular economy.

The produced pigments have already been used to create art that’s on public display. Hiromi Okumura, assistant professor and co-investigator on the project, has used the pigment in paintings currently featured in the New Vision exhibition at the Hilton Alexandria Mark Center in Alexandria. This is part of ICAT’s collaboration with the City of Alexandria Office of the Arts from November 2023 to May 2024.

Food Magic pigments in use

Inception

Earlier in her career, Choi worked in branding, packaging, and product design with companies including Bluemarlin Brand Design, Lewis Moberly, and Samsung Design Europe in London. During that time, she observed problematic consumer behaviors.

“We design so many products, but at the end of their use, short or long term, the users simply discard them, whether the products have broken down or not; we produce so much waste,” Choi said.

Before moving to America for her faculty appointment, Choi visited K-12 schools in Blacksburg to find a potential school for her children. She witnessed an enormous amount of food being wasted at schools; that experience troubled her.

“How much food was not eaten yet thrown away in the cafeteria was a culture shock to me. I had never actually witnessed anything like that until that very moment,” said Choi, who previously lived in England. “The school my son eventually attended struggled with recycling on multiple levels. For instance, at lunch, there was no food waste bin or recycling bin, just one huge garbage bin for mixed waste.”

That day, she set off on a mission to tackle the food waste problem she observed.

The recycling process

Choi’s effort to recycle food waste focuses on changing behaviors and utilizes a co-design approach, which incorporates feedback from users throughout the creation process.

She collaborated with Lee Worley, one of three art teachers at the Blacksburg Middle School, to begin a school-wide food recycling effort and conduct a two-day art workshop with his eighth grade students.

“I thought that the pigments were great. Choi’s project is amazing, and I’m hoping that something larger can grow out of this,” Worley said.

The conversations with the students revealed the methods they believed would be most successful in encouraging their peers to actively participate in the first step of the process – sorting waste.

“People often get confused about what goes where, when, and why. So we designed these three color-coded bins to guide them in the sorting,” Choi said.

Over a few weeks, the 3D-printed bins collected green, orange, and purple foods from more than 1,000 students in the school’s cafeteria. The waste was kept refrigerated between collection and extraction.

The extraction of pigment from the food worked by adding the waste into an extractor and boiling its content. Upon cooling down, the solids were then separated from the liquids.

The pigmented liquid was then transferred to an evaporator for dehydration, leaving a sticky concentrate to be mixed with a stabilizing agent. The mixture was mulled on a flat glass surface until it was smooth and homogenous.

At this point, the paint could be used, further diluted, or freeze-dried for later usage. During the workshops, students were encouraged to paint with the new products, hoping they would see the useful nature of the now-recycled waste.

 “The watercolor pigments made out of food waste were indiscernible from the type of cake watercolor that we use in the classroom. These pigments reacted the same, the colors were the same, though the kids were a little sensitive to the fact that the food did smell like food,” Worley said.

Unlike many commercially available paints, the pigments produced during this process can decay back into the environment.

“Once artificial paints dry out, they get thrown away or go through the sewage system, thus polluting our waters and ecosystems,” Choi said.

 While the pigments are currently used mainly for watercolor, Choi is exploring collaborations to find sustainable ways for oil extraction to be used as a binder and produce higher-density paint in the future.

Impact on the community

The co-design nature of this project has fostered a collaborative environment for faculty members, students, and the community and provided valuable data related to behavioral changes and recycling food waste.

As a part of the workshops, Choi used feedback cards and informal conversations to gauge the impact it had on the students.

According to the responses, 90 percent of students surveyed reported learning food waste has value by being converted to natural paint and 61 percent said they want to share this new knowledge at home.

The project has also impacted those who helped make it possible.  

The resulting unusable biomass residue can be composted or thrown away upon extracting the pigment. This substance inspired Avery Gendell, a master's degree candidate in architecture working on the project.

“I learned a lot about design for behavioral change using the co-design approach, both of which were relatively new to me. Now, I am interested in the potential of growing mycelium composites using this mushy byproduct as a substrate instead of discarding them or composting them,” Gendell said.

Since the middle school workshops, Food Magic has expanded to other local organizations.

“We collaborated with Blacksburg Middle School, the YMCA, Wonder Universe, and the Fine Arts Center for the New River Valley. They all wanted us to set up programs and workshops with them and expand this project,” Choi said.

The Virginia Tech Science Festival, Hokie for a Day, and ICAT Innovation Day have also offered outlets for the project to engage with the community.

Food Magic has already inspired other projects with a similar theme. Choi is currently in the beginning stages of ToySphere, a project that aims to transform the relationship between consumers and end-of-life toys.