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The rationale for the use of fungi in treating waste streams from food processing plants I~as been that of incorporating the dissolved and suspending nutrients into a macroscopic organism which can be filtered out readily. In order for a process using fungi to meet these objectives we examined a strain of fungi, Aspergillus fumigatus, which grew well on a variety of polysaccharide-containing materials and showed both efficient BOD removal and high quality protein recovery. In this experiment the fungal choice was based on the laboratory screening studies where t;1e criteria used was BOD and COD reduction, growth response, mycelial yield, and the ability to compete with the natural flora. In the fermentation system used far the continuous culture of Aspergillus fumigalus the best combination of operating variables, inoculum ratio, temperature, initial pH, fermentation time and agitation rate was 5%(v/v), 35∼40℃, pH 4.5∼5.0, 2days and 150rpm, respectively. The fungus reduced BOD and COD to 94.0 and 90.4%, respectively and 3,15g of dry mycelium per liter of alcohol waste was harvested during 48hr of incubation time. The protein efficiency ratios for the control diet and the experimental diet containing the fungal protein were 3.42±0.15 and 3.40±0.43, respectively.
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