Pathogens on farmers’ market and grocery store whole chickens: does location matter?

We eat a lot of chicken. I either stuff a whole chicken with lemons or onions and oven-roast (in the winter) or use indirect heat outside with a 3/4 full beer can stuck into the bird’s, uh, cavity (in the summer). Regardless of where we happen to be shopping (farmers market or a grocery store), I pick one up pretty much every week. I assume that the raw product is covered in Salmonella and Campylobacter so I try not to cross-contaminate and use a digital tip-sensitive thermometer to ensure my chicken has reached a safe temp. I’m doing what I can to reduce risk of illness. Bringing less pathogens into my kitchen would further reduce that risk.BLTYrMoCEAIRhgT

Joshua Scheinberg, Stephanie Doores and friend of barfblog Cathy Cutter published a study in Journal of Food Safety detailing a study they conducted looking at pathogen presence and prevalence on whole chickens purchased from farmers markets or grocery stores as well as produced conventionally or under organic certification. They found (not surprisingly) that there’s a bunch of Campy and Salmonella on chickens, but that there were differences between retail types.

From the article:

Chicken obtained from farmers’ markets were positive for Salmonella spp., at a prevalence rate of 28%, which was not significantly different than the prevalence of 20% found in organically processed chicken. Salmonella spp. prevalence in both farmers’ market and organic chicken however, were found to be significantly higher than that of conventional chicken. Campylobacter spp. contamination rate was found to be high in farmers’ market whole chicken, with a positive prevalence of 90%. The prevalence of Campylobacter spp. in farmers’ market chicken was significantly higher than both conventionally and organically processed chicken, while organic chicken exhibited the lowest prevalence of 28%. Within the 90 Campylobacter spp.-positive farmers’ market whole chickens, 67% were found to harbor enumerable Campylobacter spp. populations compared with 52 and 22% of conventional and organic chicken enumerable populations, respectively.

Scheinberg et al. also looked at whether pathogens recovered from farmers’ markets chickens differed whether they were frozen or fresh – as campy is pretty delicate and has been shown to be affected by freezing.

Also from the article:

To evaluate whether freezing may be beneficial for farmers’ market vendors in reducing potential pathogen load on raw whole chicken, both fresh and frozen chicken were purchased from farmers’ markets. All chicken obtained from supermarkets were purchased as fresh. In this study, Campylobacter spp. and Salmonella spp. prevalence between farmers’ market, fresh and frozen chicken were not significantly different from one another, suggesting that freezing may not reduce either pathogen to nondetectable levels. Significant differ- ences were found between the number of chickens contain- ing enumerable Campylobacter spp. concentrations above 1.0 log10 cfu/mL in frozen versus fresh chicken. This obser- vation may suggest that freezing raw chicken may not reduce Campylobacter spp. to undetectable levels; yet the lower storage temperatures may reduce higher populations of Campylobacter spp. present on the raw chicken.

This data helps farmers’ market folks make risk management decisions: While freezing isn’t going to eliminate the pathogen, it is an added step that a vendor can take to reduce how much campy makes it in to kitchens. The location doesn’t matter as much as the practices of the vendor.

The article, A microbial comparison of poultry products obtained from farmers’ markets and supermarkets in Pennsylvania can be found as an early view article at the Journal of Food Safety website.

This entry was posted in Food Safety Policy, Other Microorganisms, Salmonella and tagged , , , by Ben Chapman. Bookmark the permalink.

About Ben Chapman

Dr. Ben Chapman is a professor and food safety extension specialist at North Carolina State University. As a teenager, a Saturday afternoon viewing of the classic cable movie, Outbreak, sparked his interest in pathogens and public health. With the goal of less foodborne illness, his group designs, implements, and evaluates food safety strategies, messages, and media from farm-to-fork. Through reality-based research, Chapman investigates behaviors and creates interventions aimed at amateur and professional food handlers, managers, and organizational decision-makers; the gate keepers of safe food. Ben co-hosts a biweekly podcast called Food Safety Talk and tries to further engage folks online through Instagram, Twitter, Facebook, YouTube and, maybe not surprisingly, Pinterest. Follow on Twitter @benjaminchapman.