The potential of EtOH [64-17-5] fermn. of whey permeate as a means of whey disposal and utilization in Switzerland was explored. The effluent lactose content of unconcd. permeate can be reduced to 2% of the original value by continuous fermn. with Kluyveromyces fragilis at a diln. rate affording a volumetric EtOH productivity of almost 5 g/L-h. Although K. fragilis also completely ferments whey permeate concd. 2-fold in a batch mode with similar kinetic and stoichiometric performance, lactose uptake characteristics were quite deficient in continuous fermn. of permeates that were concd. ?3-fold. EtOH was 1 of the main inhibitors to fermenting concd. whey. In view of the possibility to remove the inhibitor online by vacuum or stripping, fermn. at high temps. by the thermophile Thermoanaerobacter ethanolicus was investigated. The preliminary results seem promising. [on SciFinder (R)]