Control of pathogenic microorganisms and turbidity in poultry-processing chiller water using UV-enhanced ozonation

UV-enhanced ozonation experiments on unscreened overflow chiller-water from a commercial poultry-processing plant successfully compared the oxidative and bactericidal effects of four treatments (viz., O-2/O-3, O-2/UV, O-2/O-3/UV, and O-2 as the control). Optimal treatments provided greater than 99.9% control of pathogenic microorganisms. Results far exceeded the USDA-FSIS requirements of at least a 60% reduction of aerobic plate count (APC) bacteria including similar reductions in coliforms and E. coli, as well as the maintenance of light transmission at a value no less than 60% that of fresh water, consequently permitting 90% recirculation of the required 0.5 gal (1.9 L) overflow per carcass. Also an additional synergistic reduction (>0.8 Log CFU/mL) in APC bacteria was documented for ozone acting in concert with UV photons as compared with the sum of the effects of O-3 and UV acting in series. Economic analysis of operational and maintenance costs for this W-enhanced ozonation system estimates annual savings of similar to $244000 in a 1/4-million bird per day plant achieving water savings of 426000 L/day (113000 gal/day).