The glycoprotein rBm86 has been intracellularly expressed in the methylotrophic yeast Pichia pastoris. A bench-scale study and rite scale-rtp of the wet-milling disruption of cells after an 80-h fermentation in methanol is reported. Retention rimes combined with different numbers of passes were used and nonsignificant differences in degree of disintegration were found above 6 min total retention rime. In addition, identical degrees of disintegration were observed in combinations adding rip to 4 or 6 min retention time. Ail energy balance yielded a clear correlation between generated hear and retention li,ne which allowed estimating the outlet temperature of the product. Furthermore, it was found that an interaction between the rBm86 protein and cell membranes offers protection and minimizes loss of the protein during the process.