Characterization and Performance Evaluation of Mycelium-Based Biofoams for Cushioning Materials Using Edible Mushrooms

This study investigated the development of mycelium-based biofoams as sustainable cushioning materials using Pleurotus ostreatus and Lentinus squarrosulus, combined with different sawdust substrates, and subjected to various pressing methods. The results indicated significant effects of mushroom species, sawdust type, and pressing method on the properties of biofoams. Growth rate, morphology, chemical composition, physical and mechanical properties, water resistance, and cushioning factor were evaluated. The results indicated that Lentinus squarrosulus (LS) exhibited faster growth rates (up to 14.37 mm/day) and produced biofoams with superior properties compared to Pleurotus ostreatus (PO). Core wood (CW) sawdust generally resulted in biofoams with lower density (0.1–0.3 g/cm3), lower shrinkage (7.17%–11.41%), and better shock absorption properties (cushion factor of 4.45–4.73). Hot pressing (HO) consistently produced biofoams with higher density (up to 0.31 g/cm3), improved mechanical strength (compression strength up to 0.53 MPa), and enhanced hydrophobicity (water contact angle up to 102.03°) but slightly reduced the shock absorption performance. Biofoam made from LS cultivated on CW sawdust and pressed using hand-packing (HP) exhibited superior shock absorption properties, achieving a cushion factor of 4.45 comparable to expanded polystyrene (EPS) foam. The findings demonstrated that certain combinations of sawdust types and pressing methods can optimize the performance of mycelium-based biofoams, making them viable for sustainable packaging applications. This study highlighted the potential of mycelium biofoams as an eco-friendly alternative to conventional packaging materials, thereby decreasing environmental impact and promoting a sustainable future. © 2024 The Authors.