Pre-Chill Antimicrobial Treatment to Enhance the Microbial Quality of Chicken Parts

Summary

Increased numbers of microorganisms on chicken parts when compared to whole broilers has led to the hypothesis that water retained during the pre-chill stage of processing harbors bacteria which contaminate parts upon cut-up. Broiler carcasses were subjected to simulated commercial processing steps from pre-chill to cut-up. Microbial populations were determined after each stage of treatment. Pre-chilling with 20 ppm peracetic acid, or 50 ppm chlorine significantly decreased total aerobic bacteria and E. coli/coliforms populations compared to the water control (p<0.05).

Situation

Salmonella and Campylobacter prevalence is higher on chicken parts than on whole chilled carcasses (26.3% and 21.4% for parts, 5.2% and 10.7% for whole carcasses, respectively). Whether the increased contamination of parts is due to the release of bacteria taken up by the muscle tissues during immersion chilling or from cross-contamination from other sources during cut-up has not been fully addressed. The objective of this study was to determine the effectiveness of applying antimicrobial treatments, including the use of a chlorine stabilizer, in the pre-chill tank to reduce the prevalence and numbers of microbes on chicken parts.

Response

Commercially eviscerated broiler carcasses were subjected to sequential pre-chill, chill, and cut-up procedures. Enumeration of total aerobic bacteria, coliforms, and E. coli was performed using carcass rinses at post-evisceration, after 15 min pre-chill (22-25oC water), after 30 min immersion chill (0-4oC water), and following cut-up into parts. Six pre-chill, antimicrobial treatments were evaluated: 50 ppm chlorine, 50 ppm chlorine+0.5% T-128 (a chlorine stabilizer), 20 ppm peracetic acid, 20 ppm peracetic acid+0.5% T-128, 0.5% T-128, and water. Addition of 0.5% T-128 to water, 20 ppm peracetic acid, or 50 ppm chlorine during pre-chill significantly decreased total aerobic bacteria and E. coli/coliforms following pre-chill by ~1.5-2.0 log compared to the water control (p<0.05).

Impact

The chlorine stabilizer, SmartWash T-128, may serve as a viable antimicrobial additive to the poultry industry when used in combination with low concentrations of peracetic acid or chlorine. Notable findings: (1) Significant decreases in total aerobic bacteria, E. coli, and total coliforms were observed following pre-chill processing steps when T-128 was used; (2) Significant increases were observed in water retention when T-128 was used compared to comparable treatments without; (3) Potential existed to retain higher concentrations of active chlorine and peracetic acid in pre-chill water containing T-128. Upon incorporation of T-128 in pre-chill water, poultry processors may be able to achieve an additional reduction in bacterial counts, an increased yield, and may be able to better maintain antimicrobial chemical concentrations at functional levels. Evidence does not support increased microbial levels on cut-up parts from bacteria in water retained in muscle. Contamination of parts during the cut-up process is more likely a possible contamination source.

State Issue

Food Safety

Details

• Year: 2016
• Geographic Scope: National
• County: Clarke
• Program Areas:
  • Agriculture & Natural Resources