Alternating current electric field inhibits browning of Pleurotus ostreatus via inactivation of oxidative enzymes during postharvest storage

Abstract

Oyster mushrooms (Pleurotus ostreatus, P. ostreatus) are rich in nutrients and have a pleasant flavour. However, they brown easily during storage, reducing consumer acceptance and decreasing market value. The present study was aimed at assessing the inhibitory effect of an alternating current electric field (ACEF) on the browning of oyster mushrooms and the possible mechanisms involved. Results revealed that treatment of P. ostreatus mushrooms with an ACEF (600 kV/m, 50 Hz, 120 min) reduced the browning of oyster mushrooms by 40% after 12 d of storage, and the effect was closely related to the inactivation of polyphenol oxidase, the delay of electrolyte leakage, and lower malondialdehyde levels that may be a consequence of decreased lipoxygenase activity. In conclusion, ACEF treatment can increase the quality of P. ostreatus during storage by delaying browning.