Exploring the feasibility of mycelium-based cups as a sustainable alternative to single-use beverage cups

Disposable paper (DP) cups, a staple in on-the-go beverage culture, contribute to environmental challenges due to their non-biodegradable polyethylene (PE) liners. This research presents an eco-friendly alternative by harnessing fungal mycelium combined with North American wetland biomass. The study evaluates three fungal species—Ganoderma lucidum, Pleurotus ostreatus, and Polyporus squamosus—cultivated on canola straw (Brassica napus L.) and cattail substrates (Typha latifolia) to produce mycelium composite materials. Among these, Ganoderma lucidum demonstrated superior mycelial growth and structural integrity when paired with cattail substrate over a 14-day period. Initial growth assessment was conducted using Potato Dextrose Agar (PDA), with further optimization through Yeast Extract Peptone Dextrose Broth (YEPDB) liquid media. The research explored the production of compostable coffee cups and mycelium sheets using a 3D poly-lactic acid (PLA) mold and aluminum foil, respectively. Mycelium composites were harvested at two growth intervals (2 weeks and 4 weeks) and analyzed for their morphological, chemical, thermo-mechanical, crystallinity, thermodynamic, and mechanical properties. The resulting composites exhibited notable thermal stability exceeding 267°C, low thermal conductivity (0.03-0.04 Wm⁻¹K⁻¹), and inherent hydrophobicity with a water contact angle surpassing at 100°. However, the mechanical properties, such as Young's modulus, were significantly lower than those of commercial coffee cup paper, with values of 11.27 MPa and 80.91 MPa for the 2-week and 4-week samples, respectively, compared to 1349.35 MPa for standard coffee cup paper. These findings demonstrate that cattail can serve as a viable substrate for producing mycelium-based bio-composites, suitable for applications requiring thermal stability and hydrophobicity.