Fungi are an important group of microorganisms in food microbiology. They are utilized for the industrial fermentation of beer and wine, production of enzymes, antibiotics, vitamins, and organic acids. These processes going on in bioreactors and fermentors which are the heart of systems used in biotechnologies. They are usually made from 316L stainless steel, but some of them are made from less expensive type, as 304 stainless steel (or 304L). For majority of processes, the reactors are operated in batch mode, under sterile or monoseptic conditions. Cleaning and sterilizing are one of the most important activities carried out in the fermentation process. Industrial bioreactors should be sterilized before inoculation because the contamination is a common cause of process failure. Stainless steels will suffer on aside the pitting and crevice corrosion when was exposed to disinfectants and on the other hand, a fungal attack by survival fungi after disinfection procedures of reactors. The effect of fungal suspensions in a disinfectant solution containing 0.25% NaDCC on the corrosion behaviour of type AISI 304 stainless steel was evaluated by linear polarization. The measurements at room temperature were made in a conventional three-electrode chemical cell, using a platinum (CE) electrode, calomel (RE) and an electrode of AISI 304 stainless steel as working electrode (WE). The corrosion process was examined by linear polarization using a Bio-Logic SP-150 potentiostate. The results shown that a synergistic effect between the (sodium dichloroisocyanurate) active substance from the disinfectant solution and fungal suspensions it is an important effect to take in account by the hygienists from food industry.
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