U.S. Poultry & Egg Assn. (USPOULTRY) and the USPOULTRY Foundation announced this week the completion of a funded research project at the Georgia Institute of Technology in Atlanta, Georgia, wherein researchers investigated the effect of peracetic acid (PAA) solutions in poultry processing wastewater treatment systems. The research was made possible in part by an endowing Foundation gift from the Stanley & Dorothy Frank Family Foundation and is part of the association’s comprehensive research program encompassing all phases of poultry and egg production and processing.

Dr. Spyros G. Pavlostathis and Dr. Jinchen Chen at the Georgia Institute of Technology completed the research project that quantified H2O2 decomposition kinetics in dissolved air flotation (DAF) effluent, as well as the long-term effect of peracetic acid (PAA) and H2O2 on the treatment efficiency of biological aerobic, nitrifying and denitrifying degradation processes.

According to the researchers, the goal of the project was to systematically assess the fate and effect of PAA solutions in poultry processing wastewater biological treatment processes typically used by the poultry processing industry and develop an effective methodology to mitigate any negative effects. The research project accomplished the following tasks: 1) Quantification of hydrogen peroxide (H2O2) decay rates under various conditions encountered in poultry processing wastewater (i.e., pH, wastewater strength, and initial H2O2); and 2) bench-scale, batch assessment of the long-term effect of PAA/H2O2 solution on the treatment efficiency of aerobic, nitrifying and denitrifying processes, as well as on the diversity and stability of microbial communities.

Researchers identified several key findings during the project. Overall, the results of the study suggests that aerobic and anoxic organic matter degradation, as well as nitrification and denitrification with poultry processing wastewater, will not be affected during the normal plant operation when residual PAA and H2O2 are not present in the wastewater. However, nitrification and denitrification will be affected when wastewater with high residual PAA concentrations are expected at the end of the plant operation shift due to emptying of chiller tanks or in the case of accidental PAA solution spills.

The outcome of the study provides systematic information to the poultry processing industry to develop a sound methodology and employ other measures that will ensure the continuous use of PAA solutions to achieve pathogen-free products, while avoiding upsets of biological processes used for the treatment of PAA-bearing wastewater.

A complete report, along with information on other association research, may be obtained through USPOULTRY’s website.