Effect of Storage Temperature on Postharvest Changes in Mushrooms1

Abstract
Mushrooms [Agaricus bisporus, (Lange) Sing.] stored at 10° and 20°C showed a sigmoid pattern of growth while at 0°C growth was retarded. The postharvest growth exhibited at 10° and 20°C could be related to a decrease in free a-amino N while at 0°C there was a significant increase in the level of free a-amino N during storage. Protease activity in the tissue increased at all 3 temperatures. It is suggested that postharvest maturation of mushrooms is supported by utilization of low molecular weight nitrogenous compounds formed through increased protein degradation. Mushrooms stored at 20°C toughened and matured faster than those stored at 10° or 0°C. Increases in discoloration during storage appeared to be correlated with decreases in total phenols and with increases in o-diphenol oxidase (o-DPO) activity. The relationship of these biochemical changes to postharvest maturation of mushrooms is discussed.