The homogenization effect in high pressure homogenizers cannot be attributed to a single physical phenomenon. At working pressures >100 MPa, high hydrostatic pressure, shear stress, cavitation, turbulence, impingement, and temperature increase have all a potential effect on microorganisms and food molecules (Figure 5). Figure 6 shows a typical pressure vs. temperature profile for a simple fluid measured immediately after the homogenization valve. Depending on the specific physicochemical properties of the fluid and the refrigeration system used in the homogenization valve case, at least a 15 to 20C shear-induced increase in temperature is typically observed per 100 MPa increment in homogenization pressure. Current commercially available high pressure homogenizers are able to reach up to 400 MPa processing pressure at low flow rates (less than 100 L/h).