Effect of initial concentration of bacterial suspensions on their inactivation by high hydrostatic pressure

Abstract
The effects of initial concentration [104–109 colony forming units (CFU) mL−1] on the inactivation of vegetative cell suspensions (Escherichia coli) and spore suspensions (Bacillus subtilis) by hydrostatic pressure treatment were investigated. The inactivation rates of E. coli and B. subtilis decreased as the initial concentration of cell and spore suspensions increased. In the practical application of hydrostatic pressure treatment, it was considered that the initial concentration of the bacteria suspensions should be as low as possible.