Pretreatment of wheat straw and solid state fermentation improves yield and biological efficiency in Pleurotus ostreatus Jacq) P. Kumm. mushroom production

The pretreatment method for generating substrate for large scale production of oyster mushroom is critical for determining high yield and biological efficiency (BE). The aim of this study was to develop an optimal storage and pretreatment procedure for substrate used in oyster mushroom production. The effect of wheat straw substrate storage (outdoor- open air versus indoor- closed barn) and pretreatment (steam (SP) and hot water (HWP) pasteurization and solid state fermentation (SSF)) on substrate microbiological quality, mushroom yield/BE were investigated during the cultivation of Pleurotus ostreatus strain HK-35. The influence of temperatures used during solid state fermentation on BE was also investigated. There were significant changes among the parameters measured (moisture, total nitrogen, ash content, C/N ratio and total microbial count (CFU) between indoor and outdoor storage. The indoor storage gave higher values. With outdoor storage, CFU showed about 800 times increase. Among the substrate treatment methodstested (SP-control, HWP and SSF), SSF gave consistently higher fruit body yield and BE which ranged from 77-86% compared to the control which ranged from 40-53%. Also SSF conducted at higher temperature (74°C) gave higher BE of 81.2% compared to one conducted at lower temperature (63°C), which gave BE of 69.4%. We consider these findings to be useful in further studies on the redesign oF industrial production systems, which can make oyster mushroom production more profitable in Ukraine and beyond.