Baker's yeast (Saccharomyces cerevisiae) cells were disintegrated in a bead mill with a multi-disc stirrer under a multiple-batch operation conditions. Continuous phase of microorganism suspension constituted of 0.1% aq. soln. of beta-mercaptoethanol containing 0.01 M EDTA and 0.001 M PMSE The pH 7 was maintained by using a phosphate buffer (NaH(2)PO(4), Na(2)HPO(4)). The degree of microbial disintegration was detd. by measuring absorbance of light with a wavelength of 260 nm. The exps. were performed at cooling the mill with 50% of a glycol soln. at 2 degrees C for the concn. a suspension 0.0005-0.20 g/cm(3)(dry mass) with adjustable speed of the stirrer (2500 rpm). An increase in the rate constant of the disintegration with increasing concn. of the suspension was obsd. Process kinetics was well described by a linear relationship at low concns. (0.05 g/cm(3)) of suspension. For the high concns. of suspension (0.08-0.20 g/cm(3)), the rate constant increased with process time. The increased concn. of released intracellular compds. and some shredded fragments of cells resulted in a increase of the disintegration rate.