Understanding the break-up phenomena in an orifice-valve high pressure homogenizer using spherical bacterial cells (Lactococcus lactis) as a model disruption indicator

The results show that the most intense break-up phenomena occur for the smallest orifice size, highest pressure, and lowest viscosity. However, at low viscosity, turbulence, together with the elongational stresses appear to be the controlling factors of cell break-up, whereas, at higher viscosities, the shear stresses become increasingly important. The occurrence of cavitation is only slightly affected by viscosity, and mainly depends on the velocities reached in the homogenization valve.