Fabrication and investigation of chitosan-based edible coating derived mushroom substrates: Efficient performance on storage and improving postharvest quality of strawberry

Abstract

Spent Mushroom Substrate (SMS) is a by-product resulting from the residual organic material left after the process of mushroom harvesting. In this research, we employed the residual biomass derived from the SMS (Agaricus bisporus). The chitosan obtained from the mushrooms was subjected to thorough characterization utilizing FT-IR, SEM, XRD, and TGA. Subsequently, the chitosan extracted from SMS was applied in the formulation of edible coatings. Within the spectrum of formulations evaluated over a period of 15 days, the chitosan derived from A. bisporus (stalk and cap) exhibited significant improvements in intrinsic characteristics, encompassing reductions in weight loss, pH, TA, TSS, firmness, and the retention of ascorbic acid (55.44 and 52.49 mg.g^-1 in comparison to 34.36 mg.g^-1 for the control), antioxidant capacity (93.02 and 92.66 % in contrast to 92.04 % for the control), anthocyanin concentration (43.97 and 41.32 mg.g^-1 relative to 31.17 mg.g^-1 for the control), phenolic content (83.35 and 83.66 mg.g^-1 as opposed to 58.48 mg.g^-1 for the control), and colorimetric properties. The chitosan extracted from SMS displayed superior resistance to decay induced by Botrytis cinerea, Penicillium sp., and Aspergillus niger in comparison to control samples over the course of the storage period. Moreover, the mushroom chitosan demonstrated minimal levels of cellulase activity, pectin methylesterase activity, and polygalacturonase activity throughout the storage timeframe. The results showed that this edible and low-cost coating has a promising effect on the preservation and sustainability of strawberries, which could overcome one of the major challenges of their preservation in different conditions.

Keywords: By-product; Decay; Edible coating; Enzyme activity; Mushroom chitosan.