Fungal biocomposites development from industrial waste

Abstract

The food manufacturing generates a large amount of organic waste. A flavor industry, for example, can generate annually 104 and 92 tonnes of mate and guarana residues, respectively. An alternative to the reuse of this lignocellulosic material would be to use them in the production of biocomposites with fungal mycelium acting as a binder of the substrate particles. Therefore, the objective of this work was to produce fungal biocomposites of Pleurotus sajor-caju using the mate and guarana residues in a ratio of (1:1) (w/w), checking the influence of the 10, 20 and 30% inoculum fraction and the drying temperature of 40°C and 60°C. For each condition tested, mycelial growth time, initial moisture content, initial drying rate, compressive strength, air moisture absorption and water uptake were evaluated. The condition determined to produce the biocomposites was 10% of inoculum and drying at 60°C, as it presented higher resistance to compression (0.094 MPa), lower absorption of water (91%), higher drying rate (27.7 g/day). The biocomposites utilise biological growth rather than expensive energy intensive manufacturing processes and require only low-cost organic waste as feedstock, can grow to fill complex geometries presented potential for packaging, as they are safe materials that have good compressive strength and low water absorption.