Fumio Eguchi*, Mami Okamoto*, Akikuni Ushikubo* and Miyato Higaki*

* Faculty of Agriculture, Tokyo University of Agriculture

+ Correspondence should be addressed to Fumio Eguchi:
(1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156 Japan)

Abstract

Twelve different kinds of excess sludge produced at wastewater treatment systems in the food manufacturing industries not only include rich nutrients but scarcely ever contain any toxic matters. Thus it is expected that those excess sludge can be employed as nutrients for cultivating edible mushrooms in the same way as food industrial wastes such as rice bran, wheat bran, etc..

In this study, edible mushrooms were cultivated in a media containing excess sludge as a nutrient. The hypha growth and fruit body yield were examined in order to reduce and reuse excess sludge. From the view point of hypha growth, it was found out that some of the media containing excess sludge from miso, soy sauce, fish paste, red bean paste were superior to the existing other excess sludge for edible mushrooms. As a result of the cultivation test, moreover, it was proved that some media, where the excess sludge had been added to sawdust, caused an increase in the fruit body yield compared with general media containing sawdust with rice bran. Accordingly, it is concluded that some of the excess sludge which was produced in the food manufacturing industries was usable as a nutrient in the cultivation for mushrooms so long as the category of the manufacturer releasing the excess sludge and the variety of the mushroom were properly selected.

Key words: food industrial wastes, excess sludge, nutritious, edible mushrooms, Pleurotus