The influence of grape pomace substrate on quality characterization of Pleurotus ostreatus —Total quality index approach

Abstract

Total quality index approach was used to reflect the quality of Pleurotus ostreatus mushroom, cultivated on grape pomace (P) as food waste substrate and wheat straw (S), in four different combined ratios: 100P; 80P20S; 50P50S; and 20P80S, with 100S, serving as control substrate. This approach involved two directions of mushroom analysis. The whole mushroom fruiting bodies analysis introduced a single total quality index (TQIM) based on 11 quality parameters. The mushroom water extracts analysis was presented by another single total quality index (TQIE), with seven quality parameters. This mathematical model revealed that the mushroom extracts have a better overall quality score with higher pomace content in substrate mixture, compared to the whole mushroom quality changes throughout the observed shelf life period. Future research may pay attention to the phytotoxicity of grape pomace as a food waste, as well as the influence of grape pomace on glucan content, as a health-beneficial compounds. Practical applications

From the sustainable part of view, advantage of this type of production is its belonging to the sustainable food waste management strategy. The main importance of food waste use is their exploitation through bioconversion process into the new value-added products, generating near zero waste. Also, the type and chemical composition of plant waste used as mushroom substrate affects the nutritional profile and quantity of the produced mushroom. Therefore, the application of this principle of production benefits winemakers on the one hand, eliminating the generation of toxic waste and protecting the environment. From a quality point of view, approach outlined in this research shows practical application of using quality index as a tool for overall quality evaluation. Finally, combining food waste for producing mushrooms evaluated through a quality index perspective paves the way for increasing mushroom in the mushroom values chain.