Unravelling the Button Mushroom (Agaricus bisporus) Browning: A Study of Enzymes and its Physicochemical Parameters

The present study screened the enzymatic profile of button mushroom across different cultivation stages and postharvest periods to understand their role in browning. The consistent presence of enzymes, i.e. polyphenol oxidase (PPO), laccase, peroxidase, phenylalanine ammonia-lyase, catalase, and lipoxygenase (LOX), throughout the growth cycle indicated their significant role in browning reactions. Browning reactions were triggered during the postharvest period, leading to variation in physicochemical parameters i.e. browning index (BI), electrolytic leakage (EL), firmness (FIR), and hydrogen peroxide (H₂O₂). BI showed a strong positive correlation with LOX (r = 0.99), H₂O₂ (r = 0.99), PPO (r = 0.98), and EL (r = 0.98). On the other hand, BI indicated a significant negative correlation with FIR (r = -0.99) and TPC (r = -0.75). These findings will be useful to better understand how shifts in enzymatic activities and biochemical responses influence browning, contributing to improved knowledge for managing postharvest quality of mushrooms.