Optimizing Pleurotus ostreatus Mushroom Cultivation on Various Agro-Industrial By-Products—Development of a Process Analytical Technology Tool for Predicting Biological Efficiency

Pleurotus ostreatus is among the most widely cultivated mushroom species on a global scale, valued for its relative ease of cultivation, excellent organoleptic qualities, and notable nutraceutical properties. P. ostreatus could use a wide range of by-products as growth substrates by excreting a potent array of hydrolytic and oxidative enzymes. In this study, a diverse range of agricultural residues and agro-industrial by-products, enriched (or not) with various supplements, was evaluated for the cultivation of five commercial P. ostreatus strains. Key cultivation parameters were assessed, including biological efficiency and productivity. A process analytical technology (PAT) approach, utilizing FTIR spectroscopy in combination with multivariate analysis, was employed to develop a predictive model for biological efficiency based solely on substrate’s spectral profile. Substrates based on wheat and barley straw supplemented with soybean demonstrated superior performance across most strains. The biological efficiency value reached 185% in some cases for a total cultivation period of only 35 days. The resulting model exhibited excellent predictive capability, with a coefficient of determination (R2) of 0.90 and low relative prediction error of just 6%. The developed innovative PAT tool will be beneficial for mushroom growers since it allows the fast and costless evaluation of agro-industrial by-products in respect to their potential exploitation as mushroom substrates.