Researchers at the University of Washington have developed a new 3D printing technique that transforms used coffee grounds into compostable packaging materials. The process, detailed in a study published January 23 in 3D Printing and Additive Manufacturing, combines coffee waste with mushroom growth to create a sustainable alternative to traditional foam packaging.
The team created a paste called “Mycofluid” by mixing used coffee grounds with brown rice flour, Reishi mushroom spores, xanthan gum, and water. After 3D printing, the objects are covered and left for 10 days, allowing mycelium – the root structure of mushrooms – to form a protective skin around the material.
The resulting material demonstrates properties comparable to conventional packaging materials. Testing showed it has similar strength and toughness to polystyrene foam, with only 7% water absorption after an hour of exposure. While denser than Styrofoam, the coffee-based material maintains a weight similar to cardboard or charcoal.
Lead author Danli Luo sees potential applications for small businesses needing custom packaging solutions. “We’re especially interested in creating systems for people like small businesses owners producing small-batch products — for example, small, delicate glassware that needs resilient packaging to ship,” said Luo.
The development addresses a significant waste stream in the United States, where over 1.1 billion pounds of coffee grounds are discarded annually. While the current process requires relatively uniform coffee grounds, limiting large-scale implementation, the research team is exploring other food waste materials for similar applications.
Source: washington.edu