Removal of Bacillus spores from stainless steel pipes by flow foam: Effect of the foam quality and velocity

Food industry cleaning operations must efficiently mitigate any risk of remaining unwanted contamination without consuming large amounts water, chemicals and energy. This study's originality was in analysing the capacity flowing foams to remove Bacillus spores from stainless steel surfaces. A set-up designed allow formation wet flow under three differing regimes: bubble-size rearrangement observed at wall with increased velocity, thus reducing efficiency. Foam 50% air/water low velocities permitted a 2 log removal B. amyloliquefaciens spores, which is comparable similar CIP conditions. Removal kinetics were modelled showing potentially very high constant rates start cleaning. Such efficient related local shear stress fluctuations capillary forces (low velocities, favorable repartition hydrophilicity bacteria spores).