Use of negative air ionization for reducing microbial contamination on stainless steel surfaces

Microbiological concerns in food plant sanitation that relies heavily on physical and chemical methods for removing and killing bacteria could be reduced by the use of non-chemical intervention methods. This initial work on the effects of electrostatic space charge on biofilms shows promise as a viable intervention option for reducing bacterial contamination on surfaces. Natural bacterial populations from a poultry processing facility were collected, allowed to multiply and form biofilms, and assessed for susceptibility to negative air ionization. A small chamber with an electrostatic space charge system was used to treat the mixed bacterial,populations that were grown on stainless steel coupons (1 x 4 cm). The object of the system was to transfer a strong negative electrostatic charge to bacteria that were attached to coupons at the base of the chamber. The system effectively decreased the survival levels of bacteria on the stainless steel, with a reduction efficiency of 99.8%. All of the swab samples taken from coupons were culture positive for bacteria, and the bacterial counts from the ionized surfaces were significantly less than for the non-ionized surfaces (P < 0.01). These results demonstrate the potential efficacy of negative air ionization against bacterial contamination on surfaces in the poultry processing environment.