Effect of Natamycin in Combination with Pure Oxygen Treatment on Postharvest Quality and Selected Enzyme Activities of Button Mushroom (Agaricus bisporus)

The combined effects of natamycin (NA) and pure oxygen (PO) treatment on microbial and physicochemical characteristics of button mushroom (Agaricus bisporus) stored at 4 ± 1 °C for 16 days was investigated. Mushroom respiration rate, weight loss, firmness, color, percent open caps, total soluble solids, microbial and activities of polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), and peroxidase (POD) were measured. The results indicate that treatment with natamycin + pure oxygen (NAPO) maintained tissue firmness, inhibited increase of respiration rate, delayed browning and cap opening, and reduced microorganism counts of yeasts and molds compared to control treatment. The efficiency was better than that of NA or PO treatment. Furthermore, NAPO inhibited the activities of PPO, PAL, and POD throughout the storage period. Our study suggests that NAPO treatment has the potential to improve the quality of button mushroom and extend the shelf life.