S. M. Russell

The Effect of an Acidic, Copper Sulfate-Based Commercial Sanitizer on Indicator, Pathogenic, and Spoilage Bacteria Associated with Broiler Chicken Carcasses When Applied at Various Intervention Points During Poultry Processing

Studies were conducted to evaluate 1) the effect of an acidic, copper sulfate-based commercial sanitizer on pathogenic, indicator, and spoilage bacteria in a model scalder system, 2) the effect of this sanitizer on total aerobic bacteria (APC) and Escherichia coli counts, and Salmonella prevalence on broiler chicken carcasses when applied during scalding or scalding and postpick dipping, and 3) the ability of sanitizer to extend the shelf-life of broiler chicken carcasses. Exposure of Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, Pseudomonas fluorescens, or Shewanella putrefaciens to the sanitizer in scalder water at 54 degrees C for 2 min resulted in complete elimination of these bacterial species. Exposure of E. coli to the treated scald water resulted in a 4.9 log(10) reduction. These data suggest that this sanitizer would be effective for use in scalders. When applied during scalding in a commercial processing plant, APC and E. coli counts were significantly (P <or= 0.05) reduced on all days of sampling. The average log10 reduction overall was 3.80 and 3.05 for APC and E. coli, respectively. Salmonella prevalence was reduced by an average of 30%. For carcasses that were scalded, picked, and dipped postpick using this sanitizer, APC were significantly P <or= 0.05) reduced on all days of sampling by an average of 1.19 log10. Escherichia coli counts were reduced on all but 2 d of sampling for carcasses scalded, picked, and dipped in this sanitizer, except for d 2 and 10. Averages on these days were higher for controls, but were not significantly different. Salmonella prevalence was not consistently impacted overall. For the shelf-life study, odor scores were significantly (P <or= 0.05) reduced for treated carcasses at d 8 through 14 of storage. The psychrotrophic plate counts were significantly (P <or= 0.05) lower on treated carcasses at d 6 through 14 of storage. This sanitizer suppressed spoilage bacteria with a 99.99% reduction at d 10 and a 99.9% reduction at d 12 of storage. This effect could result in an extension of the shelf life of the poultry carcasses by up to 4 d.

Detecting Campylobacter coli in young chicks using two different cloacal swab techniques

SUMMARY It is important to determine whether valuable broiler‐breeder chicks are contaminated with Campylobacter. It is important to have a non‐destructive method to determine whether microorganisms such as Campylobacter are present without sacrificing the animal. The objective of this study was to evaluate the reliability of cloacal swabs to detect Campylobacter in young chicks. Day‐old chicks (n = 25) were gavaged with 101‐3 or 106Campylobacter coli (C. coli) gentamicin‐resistant marker strain. Batches of chicks were placed in separate isolation units, and 7, 10, 14, or 21 d post challenge, 10 birds per group were cloacally swabbed shallow (9 mm) and deep (24 mm). Swabs were placed into 5 mL of Tecra® broth, vortexed, and streaked for isolation onto Campy Cefex agar plus 200 ppm of gentamicin. After swabbing, birds were sacrificed and one cecum was quantitatively analyzed for C. coli from the control group; both ceca from all challenged birds were analyzed for C. coli. At 14 d post challenge, 95% of the shallow and 90% of the deep swabs were positive. Even with a low inoculum of 103, C. coli achieved a high degree of cecal colonization, and the cloacal swab (either shallow or deep) proved reliable for detecting C. coli. Birds challenged with >102, after 7 and 14 d were colonized with >106 cells. After 7 d, all shallow and deep swabs were positive for C. coli, regardless of challenge dose. Since it might not be practical in industry to process the swabs the d of collection, we looked at the reliability of cloacal swabs after freezing for up to 21 days. When the level in the ceca was high, recovery of C. coli was excellent, but when the level was low (± 102 inoculum level), recovery was very unreliable. If the levels of Campylobacter are relatively high (log ≥ 6.0) in the ceca, both the shallow and deep swabs, unfrozen or frozen, are reliable, nondestructive methods to detect this microorganism.

Treatment with a low pH processing aid to reduce Campylobacter counts on broiler parts

&NA; New regulations and performance standards for Campylobacter have been implemented by the USDA ‐ Food Safety and Inspection Service (FSIS). The objective of this study was to evaluate treatment with a low pH processing aid (CMS1 PoultrypHresh), a formulated low pH processing aid, to reduce numbers of Campylobacter which could help companies meet regulatory requirements. Two experiments (3 replicates each) were conducted. Experiment 1, in each of 3 replicates, skin‐on split chicken breasts (n = 15) were obtained from a local grocery and divided into groups of 5. The skin of each part was inoculated with approximately 107 cells of a gentamicin resistant C. coli (CCGR) marker strain in an area of approximately 6.5 cm2. CCGR cells were allowed to attach for 5 min prior to treatment. Ten inoculated breasts were individually placed into separate 6 L plastic storage boxes containing either 3.5 L deionized water or PoultrypHresh solution at a pH of 1.4. Parts were subjected to agitation (bubbled air) for 25 s. After treatment, each part was removed, allowed to drain for 5 s, and placed into a plastic bag prior to mechanical rinsing with 150 mL of buffered peptone water for 60 s. Five inoculated breasts served as controls, were untreated with a dip or agitation and sampled as above. Experiment 2 procedures were repeated using skin‐on thighs under the same conditions. Rinsates were collected from each chicken part, serially diluted, and plated onto Campy Cefex agar with 200 ppm gentamicin (CCGen). All plates were incubated microaerobically (5% O2, 10% CO2, 85% N2) for 48 h at 42°C, colonies were counted and the cfu/mL was log transformed. The use of PoultrypHresh on split breast produced a 99.6% reduction compared to untreated controls, while thighs showed a 99.4% reduction. This study demonstrated an approximate 3 log reduction (P < 0.05) using a 25 s air agitation treatment in PoultrypHresh at pH 1.4 with no observable damage, which will help processors meet FSIS regulations.