Microbiology of Foodborne Pathogens and Their Effect on Food Safety

Summary: 

In this episode, Dr. Keith Schneider joins Dr. Juan Carlos Rodriguez for a discussion on FSMA’s produce safety rule and microbiology concepts related to food safety. 

In this episode, Dr. Keith Schneider discusses microbiology concepts that help farmers better understand how to produce food safely.  

 Tune in to learn about:  

• The Produce Safety Rule  
• Problematic foodborne pathogens  
• The role of indicator organisms and methods to test for their presence  
• Preventative controls 

 Resources: 

Learn more about food safety and upcoming events and webinars on our website: https://foginfo.org/food-safety-for-producers/

Learn more about food safety on the UF/IFAS Southern Center for FSMA Training website: https://sc.ifas.ufl.edu

Learn more about FSMA on the U.S. Food and Drug Administration Website:
https://www.fda.gov/food/guidance-regulation-food-and-dietary-supplements/food-safety-modernization-act-fsma 

Chapters

• 0:01 Food Safety for Farmers Podcast Series
• 9:40 Food Safety on the Farm

Transcript

Speaker 1: 0:01

Hi fresh steak listeners. This is Juan Carlos Rodriguez with some exciting news about a limited podcast series fog has recently launched. The podcast is called Food Safety for Farmers and it is part of our Road to Safe and Healthy Food Project, funded by a grant from the Food Safety Outreach Program from the USDA National Institute of Food and Agriculture. This week we want to share with you the first episode where Dr Keith Schneider, professor and extension specialist in the Food Science and Human Nutrition Department at the University of Florida, joins us for a discussion on the Food Safety Modernization Act's Produce Safety Rule and Microbiology concepts related to food safety. You can listen to the new podcast and find information about upcoming food safety webinars on our website, wwwfoginfoorg. We hope you enjoy.

Speaker 2: 0:57

Welcome to Florida Organic Growers. Podcast Series Food Safety for Farmers. A project funded by the USDA National Institute of Food and Agriculture Food Safety Outreach Program, our podcast provides information on food safety topics that farmers can use to better understand how to comply with the Food Safety Modernization Act regulations. Thanks for tuning in.

Speaker 1: 1:21

Hi everyone. We're very excited to start a new series. We're going to be talking to experts on food safety and the things that farmers need to know, especially as it pertains to the Food Safety Modernization Act, and today we're very lucky and happy to welcome Dr Keith Schneider, who is a professor at the University of Florida and a member of the Southern Center. So, keith, welcome once again. We're always very delighted to have you, and would you mind telling us a little bit about your work and the things that you do at the University of Florida and the Southern Center?

Speaker 3: 1:58

Sure, I'm a professor in the Department of Food Science and Human Nutrition at the University of Florida, located in Gainesville, florida. I'm a food safety microbiologist and for the last 22 plus years now I've been working in the area of food safety microbiology, and specifically the last several years dealing mainly with produce.

Speaker 1: 2:23

One of the things that I know, keith, from the time that we've known each other and University of Florida and Florida organic growers have been working together is that you and your partners at the University of Florida your colleagues have been doing a lot of great work educating farmers throughout the state and the Southeast region about the Food Safety Modernization Act. Today we're going to be talking specifically about the produce safety rule and food or pathogens and their microbiology. So can you tell us a little bit about the Food Safety Modernization Act and the produce safety rules? For the people who tune in for the first time, maybe they're familiar with it, maybe that's something that they've heard about but don't really quite know a whole lot yet.

Speaker 3: 3:13

Sure, the Food Safety Modernization Act was first signed into law back in 2011. And roughly five years after that it became enacted, and that's what we're operating under today. It contains numerous new regulations and guidelines and guidances, but one of the main ones is something known as the produce safety rule. That is a codified set of rules that explains or describes the activities necessary to produce safely, and that was also first enacted right around 2016. The FDA is still working on finalizing parts of that rule. It's in flux, but the whole Food Safety Modernization Act, which we call FISMA for short, and the produce safety rule are the new regulations that now govern the land, especially when we're talking about the production of produce.

Speaker 1: 4:16

So if someone's growing, packing or processing fresh produce, what exactly is it that they need to know? Does everybody need to comply with the regulation? Do people need to sort of show the government, or whoever it is, that they're complying with FISMA?

Speaker 3: 4:35

Yeah, so not everybody is going to be covered under this regulation. If folks want to look it up on the internet, the regulation is covered under what we call 21 CFR. The CFR is a code of federal regulations which is where all the laws of the land are stored, and the 21st volume, and again it used to be in books but now it's all online. In the 21st part of all this. You can look up section 112, when you can actually see all the rules written out.

Speaker 3: 5:08

There are sites within FDA that provide pretty easy to use decision trees that allow you to find out whether or not you're covered under this regulation, and it has to do with whether you're just growing, whether you're growing and packing on a particular piece of property, how much you sell in a given year, where you're selling it, whether it's direct to consumers or if you're selling it to restaurants. But as you go through the decision tree you should be able to tell whether you're covered or not. For the most part small farmers are exempt. But again, if you're not sure, you can go to the FDA and you can kind of look up whether or not you're going to be covered.

Speaker 1: 5:49

You said that, for instance, farmers who are selling directly to consumers, for example, farmers who sell at farmers markets, for instance, I used to be a manager at one of the farmers markets here in Gainesville and I did, every now and then, talk to some of the farmers there and actually in the beginning, when we were hearing about fees, mines, they were all very worried worried in terms of what it was that they needed to do.

Speaker 1: 6:17

Now. Was there going to be additional paperwork and some of these other things that can be a concern in terms of how much work is it going to be to show that you're compliant? Because the one thing that they always would say is that no farmer wants to make anyone sick. They, I think, are trying as much as possible to be very careful how they handle produce when they're harvesting or packing in some of these other things, but it goes beyond just yes, they don't want to cause any problems whatsoever, but what exactly is it that they should really understand and know about? Food board pathogens, and what is some of the work that you guys are doing to educate farmers about these food board pathogens?

Speaker 3: 7:01

Yeah, so the basic underlying goal of this program and any of the regulations really are to again produce safe food. The amount of work involved really depends on, again, a lot of different things that we may not have time to cover Again whether or not your commodity is eating raw, whether or not it's typically eaten or it's cooked by the consumer. But the overlying goal is to make sure that we're producing safe food. We're protecting against typically three different types of hazards, one being biological hazards, the other being chemical and physical, and most of the energy and effort within the Produce Itzoo Rule really goes around preventing microbial food board pathogens.

Speaker 1: 7:51

And that includes things like bacteria and viruses and parasites.

Speaker 3: 7:55

Yeah, so the three different types of hazards again biological, chemical and physical ones we worry about. When we break down biological, those are broken down into other subcategories things like bacteria, and common examples are things like salmonella or E coli, listeria, viruses, organisms such as hepatitis or norovirus. And then we have parasites, and sometimes you'll see this listed as protozones, but really we're talking parasites, and common ones associated with produce are things like cyclospora or cryptosporidium, and each one of these has their own unique growth and survival characteristics. And the more you know about each one of these and where it's typically found and what commodities are typically associated with it, the more proactive the producer can be and the less likely one of these is going to make it to a consumer.

Speaker 1: 8:54

And so, in terms of being proactive and some of the practices that you all typically go around and inform farmers about, what are some of these practices that they need to do? Can you give us and share some of the examples in terms of how to prevent the growth of microorganisms, for instance, or perhaps dealing with making sure that the conditions for the growth are not adequate for these pathogens to reproduce?

Speaker 3: 9:24

Yeah, sure, that's what we look at. This Proditive Safety Rule in general. It's sort of like good agricultural practices. So if farmers are familiar with the good agricultural practices programs, which were voluntary, the Purdue Safety Rule pretty much follows that. So we're going to worry about worker health and hygiene. We're going to worry about wildlife intrusion, the safe use of manures or composts, we're going to worry about our pre-harvest and post-harvest water use. And then there's whole modules on record keeping and how to define you know how to put together a food safety plan for your establishment.

Speaker 3: 10:04

So a lot of this again is stuff that most farmers are doing already. Classic example if we're talking about worker health and hygiene, we're making sure those workers are washing their hands after using the restroom. That's one of the most common things. It's hard to believe that we're still talking hand washing, but it's one of the five major causes of foodborne illness. Again, workers or employees just not washing their hands, and that one small effort upon, you know, making sure that workers are washing their hands, prevents a lot of potential foodborne illnesses. A lot of illnesses are spread by people using the restroom, feckling, contaminating their hands, then touching product and that product is consumed by a buyer and then they come down with that same illness. So that's one example.

Speaker 3: 10:53

Another one is making sure that your irrigation water is adequate for use.

Speaker 3: 10:58

Now, if you're using municipal water or well water, those are typically free of the pathogens that we you know, we just mentioned. But if you're using surface water, there's a potential. If that water has come in contact with, say, a cattle operation or is been contaminated by, maybe a leaking septic system in the area, that untreated surface water now has the potential for harboring some of these microorganisms. And if we were to spray them, say with overheating irrigation, directly on the edible portion of a commodity we're going to be harvesting, then the likelihood of a consumer ingesting that and coming down with that illness goes up. So water use is going to be huge. Application of manure Another classic example. If we're using raw or improperly composted animal manures and we call them biological soil amendments of animal origin, if we're using something like that, again that has the potential for harboring some of these microorganisms. And again, if we apply them at a point where they're close to harvest, they may make it to the consumer and again cause some problems.

Speaker 1: 12:09

One of the things that we're going to be doing during the Road to Safe and Healthy Food podcast series is talking specifically about some of these things that you've mentioned. We do have an episode plan to talk about water and water use and irrigation and some of the things that you've mentioned. So I invite everyone to stay tuned, because we are hoping to be able to cover a lot of these topics during this series and, of course, we welcome people's emails and questions about some of the things that you want to find out more during the podcast series. Are there ways that farmers can continue to be proactive and perhaps even test for some of these pathogens?

Speaker 3: 12:55

That's a great question. Currently, there is a testing requirement written into the rule which we're looking at, what we call an indicator of microorganisms, and that indicator of organism is a generic E coli. E coli is an organism we typically found with feces. So if you have generic E coli, then there's a big potential that you might end up having a pathogen. There is another camp, which I'm not part of, that would love to test for individual pathogens specifically. The problem with that is we're looking at, you know, 10 to 30 different pathogens that we worry about on any given day. Thus, testing for one, you miss 29 others. So indicators, while not perfect, seem to be the way to go. Fda is still exploring this. Actually, the water regulation within the Produce Safety Rule is still being analyzed. It has not been finalized, so there's going to be some changes in the future.

Speaker 3: 13:56

But testing one of the easiest things that you know a producer can do is if they you know they have a well, they can test it for E coli and whether or not that well is intact. For those using, say, municipal water for packing, they have a small enough operation. They can rely on municipal water. They really only need to have the certificate from your city or or township that says that you know that water is clean and typically we get those, you know, on an annual basis. But testing individual pieces of produce for pathogens is probably not an activity that is going to yield a lot of useful results.

Speaker 3: 14:37

If you're worried about salmonella, testing individual fruit for salmonella is probably not going to provide much benefit.

Speaker 3: 14:44

I mean, it's so rare that you come across something like that You're talking. Maybe you know one or two per thousand that your chances of catching it on a couple of small little grab samples is very low. The best thing a farmer or producer can do is really follow the rules Again making sure workers wash their hands, making sure they're applying their water safely and making sure, if they're using untreated surface water, that maybe they're using a drip or microjet type of irrigation or seepage. So it's one of those things where individual testing probably not testing the water, because water has the largest potential for spreading microorganisms making sure that's of adequate quality for its intended use is probably something you can do. Unfortunately, we don't have any codified regulations right now. There were some that were out there, but FDA is rethinking their whole strategy. So if they do go to the website and read the FDA's guide on, you know, water testing. Just knowing that that's all going to change in the next couple years.

Speaker 1: 15:47

So, if I hear you in terms of because you've mentioned it a couple of times the best way to prevent from being in contact with things like E coli or Salmonella is to follow these guidelines. Proper hand washing is one of the best ways to do that. And are there any other things that you are recommending to farmers when it comes to, especially because this is one question that we actually have heard from our farmers a couple of times is how to best deal, and they don't always know whether or not their practices are enough right now, especially with the proteins to E coli and Salmonella.

Speaker 3: 16:29

Yeah, for certain things like that, from a from the farm perspective, again, knowing your water quality is one, preventing animal ingress into the field or in some cases you can't exclude all wildlife not harvesting produce that is near or visibly fecalic contaminate it. So that's one thing you can do. And, again, just being conscious of where these organisms are introduced, again typically through fecal contamination, and then making sure that we avoid that as much as possible. Now, at the packing shed side, sometimes we'll worry about other microorganisms, things like listeria monocytogenes, which is less of a fecal associated pathogen and more of an environmental pathogen. And there we want to do proper facilities, sanitation. At that point we're going to be washing down the facilities, hopefully every day, or as much as we can, making sure surface food contact services are clean, using the appropriate food grade sanitizers and making sure we avoid the buildup of something like a biofilm. And for those who don't know what a biofilm is, if you, if you have a pet and you want to get up close and personal with a biofilm, just fill your pet bowl. After a couple of days of not changing the water, that little slimy layer, yeah, you're feeling at the bottom of the bowl. That's a biofilm, that's a growth of microarray. It has been, in this case, benign. But we have biofilms everywhere. We build them. We build them up in our mouths, they're in our sinks and our drains and in a processing environment.

Speaker 3: 18:05

While biofilms themselves might not be considered harmful, pathogens such as listeria monocytogenes can sort of hitchhike into these biofilms. So if we allow these to establish, we set up a situation where a pathogen like listeria monocytogenes can set up camp, not only hide, but survive and then multiply, and in those environments now we can really make a very small problem. It's a very large problem and one thing that kind of let everybody know there's no way and I don't think there's an expectation by FDA either that we're going to eliminate all bacteria from the environment. We're not going to eliminate all pathogenic bacteria from the environment. Well, our goal is is to keep the amount or the levels of these organisms. It's such a level that they're not going to cause illness. So when I'm looking for a sterile environment, what we're trying to do is keep the level of these, these pathogens, as low as possible and that way we can reduce the risk to as low as possible as somebody getting a foodborne illness.

Speaker 1: 19:12

Great. So these are all very valuable information and we'd really appreciate you sharing these with us. Can we run by the main things that we've discussed during today's episode? In terms of the biological hazards, You've mentioned that there's three main groups the bacteria, the viruses and the parasites and Obviously they all have their own characteristics and how maybe remind people the best ways that we or farmers can deal with those biological hazards and prevent them.

Speaker 3: 19:50

Sure. First thing again, getting a handle on the different types of organisms, because we lift them all as biological hazards or pathogens and they behave really differently. So organisms such as bacteria, which are just single cell microbes, can actually grow and multiply. So we want to try to exclude those as much as possible. And again, they like water and food. Thus if you have damp environments where you have a lot of debris on the floor, on your packing lines, they can actually multiply and again make problems worse.

Speaker 3: 20:25

Things like viruses and parasites won't multiply in the environment without a host. So many parasites and some viruses have animal reservoirs. So excluding animals from as much as possible from the farming area helps reduce the potential for having parasites. Viruses, specifically norovirus and hepatitis, are typically associated with human beings. So if you have an ill worker that's showing signs of illness, you don't want them around your food because again they have the potential for spreading these things. So knowing how these things survive and where they come from is critical. So if you know you see a cow, the first thing my mind goes to is oh, that's potential for a pathogenic E coli. I should not let that cow in my field. Or if I see any type of scat in the field that has the potential for carrying my microorganism, I'm not going to harvest the plant that happens to be next to that particular vehicle material. So those are the things that one you can do From an operation standpoint keeping the facility clean, using the proper sanitizers to remove these microorganisms and preventing the growth, preventing the buildup of a biofilm that's critical.

Speaker 3: 21:37

And again, just knowing what sanitizers are effective and making sure you're using them properly. That's always another good advice is, again, whatever you're using, make sure you're using it at the concentration that's recommended. And then it's for whatever surface, whether it be metal or PVC. You want to make sure that that particular sanitizer is going to be effective for that particular material, for the organism that you're trying to control, and you would work with your chemical supplier to make sure that you got the proper chemistry to take care of that. So those are the things that the average person can do and there are some testing methods and typically you're not going to be doing those because, again, that whole needle in the haystack.

Speaker 3: 22:23

But you may have a buyer that says, hey, we'd like you to test, maybe do a play count, maybe do something called PCR polyminous chain reaction type test to make sure that their product is not contaminated in any way. And you might have to do some of those tests and again, understanding what the utility of each of those tests were and what it will tell you, what those results tell you and what they don't tell you is also good, just kind of familiarizing yourself with any method that somebody asked you to do. Go on the internet and read up on it, because it'll help you understand and interpret those results that you get and, again, learn as much as you can. There's a lot of free information out there.

Speaker 3: 23:06

Again, other than being a research and teaching professor, I also do extensions. So we do a lot of extension outreach, we do a lot of food safety trainings and we go out and we train our stakeholders, the farmers and the packers. We do one or two trainings every single month. So we're all over the state trying to educate and trying to keep everybody up to date on what FDA is setting out for us to do.

Speaker 1: 23:32

Yeah Well, keith, thank you again. We love having you. As I said and always say, you're a great resource of information, especially as it pertains to the Food Safety Organization Act. I encourage everyone to visit the Southern Center website at the University of Florida for more information Out of contact Keith and his colleagues and some of the work that they're doing. I also invite everyone to tune in to our next episode and thank you so much for joining us again today.