Rehydration conditions of dried Shiitake mushrooms.

Abstract

Dried Shiitake mushrooms rehydrated under various conditions were cooked and erences between the cases of Donko and Koshin varieties, the cooked mushrooms which soak ed at 5°C for 5h or more and at 25°C for 5 to 15h were preferable. On the whole, the mushr ooms soaked at 40°C were evaluated to be not preferable, however, some of them soaked for a short time were relatively preferable. The impression for taste of the cooked Shiitake was correlated with the intensities of umami and bitterness. The increase of umami h eightened the impression score for taste. On the other hand, bitterness provided bad effec t on its score. The score for intensity of umami in cooked dried Shiitake was correlated with the concentrations of 5'-GMP and glutamic acid. The content of hydrophobic amino ac ids in dried Shiitake cooked after long time soaking at high temperature were enough to cause bitter taste. Since the mushrooms, which generated much 5'-GMP and contained le ss hydrophobic amino acids, were scored highly for taste and consequently gained a good overall estimate, it was suggested that the soaking for a shorter time at lower temperature was desirable. However, the one soaked for too short time was not thoroughly reh ydrated, so scored lower points for texture and consequently not prefered. (Received Jul. 7, 1988)