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The Expert Answers Q&As and columns reflect the expertise and opinions of individual faculty members and do not necessarily represent an official policy or position of the university.

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Rodney Tollerson

In the wake of the recent E. coli outbreak linked to carrots, and with the Thanksgiving holiday right around the corner, concerns about food safety are at an all-time high. In this Auburn University Expert Q&A, we sit down with Assistant Professor in the Department of Biological Sciences Rodney Tollerson to discuss the recent E.coli outbreak affecting carrots.

Can you describe the latest E. coli outbreak recall and how it’s targeted toward organic carrots?

RT: Currently this recall has been traced back to a company called Grimmway Farms, an organic produce company who did a voluntary recall of all of their carrot products. 

It's a specific strain of E. coli, different than the previous breakout that had to do with onions. That was E . coli O:157 H:7, this outbreak is E.coli O:121H:9. Those numbers and letters represent the way that our immune system recognize the pathogens. They're both E. coli, but the antigen from the E. coli is different. They both cause the same disease. They have the same toxin. 

Is it just organic carrots?

RT: Yes, it’s just organic carrots that are affected. Normally, because of how our farming system works, there won’t be a crossover between an organically farmed crop and a conventionally farmed crop.

So, if there was an issue with a plot of land that was specifically for organic farming, it’s only going to stay within that plot. If there was an issue with a conventionally farmed piece of produce, then it would impact that specific plot.

Should people stay away from carrots this Thanksgiving? What if they already purchased a bag?

RT: Carrots are a major holiday staple. I want to make clear that we should not be afraid of carrots. Feel free to get carrots from the grocery store, even organic carrots. This is only for Grimmway Farms organic carrots with recalls for specific “use by” or “sell by” dates. For whole carrots, the “use by” dates are Aug. 14 through Oct. 23. For the baby carrots, the “use by” dates are Sept. 11 through Nov. 12. These carrots are likely not going to be on the shelf. Any carrots that are on the shelf are, more likely than not, are going to be safe since the “use by” date should be after those date ranges.

If you already have carrots in your refrigerator, go back and check the dates. If it falls within the recall dates, I would go to the FDA website.

What should people do to prevent contracting E. coli and making sure other holiday food is not contaminated?

RT: When you’re handling both uncooked meat and vegetables, the way we often do for Thanksgiving, you want to make sure that the two do not come into contact. If you are cooking a turkey with stuffing and vegetables, make sure you cook the turkey longer than you would cook a turkey without stuffing. If the temperature of the turkey and the center of the stuffing have not reached a safe minimum internal temperature of 165 °F, further cooking will be required, according to the USDA. The heat dissipation in the turkey is going to be different. You also want to make sure that if there are any juices from a turkey that may be contaminated with E. coli or any other pathogen, they don’t get your vegetables. You also want to make sure your vegetables get cooked to a high enough temperature. The major thing is, 

  1. Separate the produce and the meat until they’re being cooked, do not let uncooked meat touch produce that you are not planning to cook with the meat.

  2. When they are cooked, you want to be 100% sure the meat is cooked to the right internal temperature, so that if there were any pathogens, they’re not going to contaminate your vegetables down the line.

How does the research that you do here at Auburn impact your expertise on food safety and contamination?

RT: One of my major points of expertise is understanding the way that microbes respond to environmental stress. Those stresses can be going from one temperature to another, finding out what the different mechanisms they use to protect themselves from dying off at a certain temperature, exploring how they know if they’re in a human host versus if they’re out in a field and more. These are the things that I am really interested in. My favorite thing to say is that microbes don’t have eyes, so they can’t see where they’re at. They have to use different mechanisms to understand where they are.

When E. coli produces these toxins, it only wants to produce them when it’s inside of a host. It does not care about producing them when it’s not. These things are all controlled by the environment that the organism is in.

Do you have a good rule of thumb when it comes to cooking a stuffed turkey?

RT:If you’re cooking a stuffed turkey, you need to make sure that the stuffing itself is the right temperature. That’s the most important thing. If you’re stuffing, check the turkey temperature, but then check your stuffing temperature to make sure it hits 165 °F as well.