Abstract
The relationship between the freshness and protease activity of bunashimeji mushroom (Hypsizigus marmoreus (Peck) Bigelow) and oyster mushroom (Pleurotus ostreatus (Jacq. et Fr.) Kummer) was examined.
The overall protease activity of oyster mushroom, although having a shorter shelf life, was higher than that of bunashimeji mushroom. While the activity of bunashimeji mushroom increased during storage, the activity of oyster mushroom was already high when purchased and changed little afterwards. The protease activity of oyster mushroom immediately after harvesting was low, but this rapidly increased during storage. The structural protein of oyster mushroom was degraded during storage.
These results suggest that the protease activity of oyster mushroom increased with the deterioration in the quality even before purchase.
