Structural modification of Pleurotus ostreatus pelletized mycelium for texture-tunable crispy food applications

Intact mycelium pellets represent a promising structural format for novel food design due to their naturally porous architecture that can support ingredient imbibition and texture development. However, their potential as discrete edible scaffolds remains largely unexplored. This study investigated the utilization of Pleurotus ostreatus mycelium pellets as edible porous scaffolds for developing dry, crispy snack structures via ingredient imbibition and freeze-drying. The pellets were characterized for morphology, hygroscopicity, mechanical properties, color uptake, and microstructure. Results demonstrated that ingredient imbibition induced distinct concentration-dependent mechanical responses. Specifically, 10% (w/v) inulin-agave (IA10) treatments yielded the most favorable balance of hardness and crisp fracture behavior while retaining the discrete pellet morphology. Hardness increased from 0.19 ± 0.08 N in control pellets to 0.75 ± 0.28 N in IA10 treatments, with a significant shift in crispness from a median fracture count of 0 (control) to 4 (IA10). Scanning electron microscopy (SEM) observations confirmed suggested that ingredient incorporation led to was associated with densification of the internal hyphal network and reduced porosity, thus supporting a mechanism of solute-scaffold reinforcement for texture tuning potentially contributing to reinforcement behavior and altered texture properties. Furthermore, incorporation of natural pigments demonstrated the preliminary feasibility of using mycelium pellets as carrier matrices for functional and sensory additives. These findings highlight the potential of intact fungal pellets as tunable edible scaffolds for texture and functionality design without extensive mechanical restructuring. This work provides a simple, conceptually scalable strategy for developing sustainable and dry and nutrient-dense mycelium-based foods, expanding the application of fungi in the next-generation of functional foods.