Effect of maturity stage on quality and selected enzyme activities of white button mushroom (Agaricus bisporus) during storage

Abstract

The effect of maturity stage on quality and selected enzyme activities of white button mushroom (Agaricus bisporus) during storage at 4°C for 14d was investigated. The harvested mushrooms were sorted into four stages of maturity according to the cap diameter: stage 1, 2.5−3.5cm (veil intact); stage 2, 3.5−4.5cm (veil intact); stage 3, 4.5–5.5cm (veil intact); stage 4, >5.5cm (veil opened). Results showed that higher weight loss, respiratory rate and browning degree were found at veil opened stage, whereas greater firmness were encountered at veil intact stages. The highest superoxide radical production rate and malondialdehyde level were also observed at stage 4. However, A. bisporus harvested at stage 3 exhibited the highest hydrogen peroxide content. In addition, enzymatic assays showed that A. bisporus harvested at veil opened stage had lower superoxide dismutase and peroxidase activities, however, higher polyphenol oxidase activity than that of other stages. This indicated that the balance between reactive oxygen species and antioxidants had been seriously destroyed for mushroom harvested at veil opened stage during storage. Thus, A. bisporus should be harvested at stage 3 for better postharvest preservation.