Preview Mode Links will not work in preview mode

Our lives are frequently and significantly affected by food. Because we must eat to survive, many human cultures have developed with food at their very core. The goal of this podcast is to explore the complexity and nuance of the global food system, celebrate the progress we have made, and debate the best ways for humans to proceed forward into the future. 

You can subscribe to this podcast on your preferred platform by clicking any of the buttons below.

Captioned episodes are available on our YouTube page

View our website for further information regarding the Global Food System Initiative. 

May 18, 2021

This week, Dr. Sara Gragg, associate professor of food science in the Department of Animal Sciences and Industry, discusses how and where pathogens access meat. The study of E. coli, salmonella and other toxin-producing pathogens has been a major focus of researchers at Kansas State University for many years. Gragg has presented extensively on the topic of food safety and studies processes in food safety and microbiology. Her research program investigates pre- and post-harvest issues affecting the meat and produce industries, with specific interests in addressing how pathogens contaminate food products and the application of interventions to prevent or reduce pathogen presence.

 

Transcript:

[Music]

 

Something to chew on is a podcast devoted to the exploration and discussion of Global Food Systems produced by the Office of Research Development at Kansas State University. I'm Maureen Olewnik, coordinator of Global Food Systems.

 

And I'm Colene Lind, Associate Professor of Communication Studies at Kansas State. I studied the public's role in science and environmental policy.

 

And I'm John Fabian. I'm a food scientist.

 

The safety of the food we eat is important to everyone. Studies of food contamination with E coli, salmonella and other toxin producing pathogens has been a major focus of research at Kansas State University for many years. Questions on pathogenic contamination in meat and how the organism enters into that food system are at the center of research activities in several disciplines. Today's guest is Dr. Sarah Gragg, associate professor in the Department of Animal Science and Industry at Kansas State University. Her research program investigates pre harvest and post harvest issues affecting the meat and produce industries with specific interests in addressing the manner by which pathogens contaminate food products, and the application of interventions to prevent and or reduce pathogen presence. She is particularly interested in studying the pre harvest transmission of foodborne pathogens in food animals, as well as investigating interventions to reduce foodborne pathogens in live animals. I would like to welcome Dr. Sarah Gragg to the podcast, something to chew on. We're looking forward very much to having a discussion with you here today. Before we get started on some of the technical side of what you do, can you give us a bit of background on yourself, who you are, and how you got interested in the work that you do?

 

Yes, absolutely. My pleasure. Thank you, Maureen. And thanks to the entire team for inviting me today. I really enjoy the opportunity to be here with you and visit with you about my passion, which is food safety. So with that I'll share a little bit about how I came to be a food safety researcher. I was actually in high school and walked into my Agriculture class as a freshman didn't know what to expect. And we had a new teacher that year. His name was Todd Berkshires and he was starting us off on our Agriculture classes but also in taking our FFA program forward as well. We had a co-advisor, as well, in our FFA program. And so I got to know these two teachers interacted with Todd Berkshires the most and as part of FFA, we have to have something called a supervised agricultural experience program or an SAE for short. And, I grew up right outside of Lincoln, Nebraska. And I had like two or three acres and had some close friends that I also would show and train horses with, and so, I was definitely a part of agriculture but I wasn't per se the traditional farm kid if you will. And so, I didn't know what I was going to do for my SAE program. And his wife, Dr. Mindy Berkshires was a brand new assistant professor at the University of Nebraska Lincoln at the time. And he said why don't you go work with her in the lab because food science and technology is actually an SAE emphasis area. And we can see if maybe that's something that you want to do. And I said that sounds fantastic. And so I got to meet Dr. Berkshires and spend some time getting to know her and her graduate students and getting to know the lab and decided that was absolutely what I wanted to be doing for my SAE. And so, I was very fortunate at the age of 14 to sort of luck into food science, if you will, I don't think I'd ever heard of it or known what it was at the time. And so as a part of my FFA program and working with her in the lab, I was able to complete some different research projects for science fairs, and different other competitions and activities through FFA. And so I got to work alongside her and her graduate students while also logging hours for my SAE. And so, after several years of that, I realized this is what I want to do for my career. This is something I'm passionate about. Something's very interesting to me. And I also really enjoyed agriculture and wanted to make a career out of it. So really with that the rest is history. I stayed at Nebraska, to do my undergraduate in food science and technology. And about the time I was a junior in high school, the Berkshires family relocated to Texas, to Texas Tech University. And at the time, I knew that I was going to be following them for graduate school. So I stayed at Nebraska did my bachelor's and then transferred to Texas, to attend Texas Tech for my masters and my PhD. And so while I was there, my master's work consisted of looking at lactobacillus, and some different strains, as an intervention to control E coli. Oh, and 5787 in fresh spinach. And so, produce safety was really the focus for that degree. But at Texas Tech, we had a lot of exposure to meet safety, as well as pre harvest safety, working with cattle, and other animals as well. So then, I stayed at Texas Tech for my PhD, again with Dr. Berkshires, and worked on cattle lymph nodes, actually, and trying to isolate salmonella from cattle lymph nodes. So looking at the prevalence, which is how many animals out of a certain population have salmonella in their lymph nodes, and also trying to quantify how much salmonella was present as well. So looking at prevalence and concentration.

 

And so that actually was my entire Ph. D. program. So did that for my dissertation work. And we worked with both domestic cattle as well as cattle in Mexico for the various parts of my project. And we also worked with the United States Meat Animal research center in Clay Center, Nebraska, for a large portion of my dissertation work. So that was what I was up to, before I came to Kansas State University. I did a little bit of a postdoc at Texas Tech as well. And then this job at K State came available. And I have been with Kansas State ever since. And so I joined in June of 2013. And I'm currently an associate professor with a 60% research 20 or 40% teaching appointments. So that's a little bit about how I got to this point in my career.

 

That's great. Thank you very much. You know, looking through the research activities that you've been involved in, it's covers quite a bit of distance, I'm going through the leafy greens and the produce side of it into the animal side. You know, you talk a bit about calorie search. Have you done research on other animals as well?

 

Yes, actually, so cattle is definitely probably the area that I've researched the most in terms of live animals or in terms of livestock, but also have done some work with swine. We actually as a food safety team here at K State have wrapped up recently two studies looking at hog carcasses. One study was looking at salmonella from carcasses all the way through trim, and trying to identify interventions that are effective at reducing salmonella. And then we did what I would call it that project sister study where we were looking at reducing ShiGa toxin producing Escherichia E coli on carcasses. And so, that those are probably two of our most recent studies. And then we also are working on a collaborative study that just got funded with Texas Tech University to look at salmonella in hog lymph nodes, as well. And so that's going to be as I mentioned, the dual institution project, where we're going to look at a variety of different hog lymph nodes, from hogs around the country with different plants, and both trying to determine prevalence as well as concentration of salmonella. So really, beef cattle and hogs are probably my two main livestock I've worked with.

 

I'm curious on the the lymph node work, and this will be a question of based on ignorance. How does the contamination in that part of the animal's body impact human food consumption?

 

This is a great question. So I'm going to focus primarily on beef cattle because that's where a lot of the lymph node work has been done to date and that's where we have the most data. So we have looked, a lot, at what are called peripheral lymph nodes, so those are lymph nodes that are sort of on the outside of the body embedded in the fat tissue of the carcass. Now, when beef cattle are taken apart, which we would consider fabrication, there the fatty tissue oftentimes gets cut away and is sent with trim to grinding. Since those lymph nodes are a part of that fatty tissue, those lymph nodes then can sometimes get incorporated into ground beef. So when we have lymph nodes that have salmonella in them, those lymph nodes then are in the fatty tissue, the fatty tissue goes to ground beef, and then any salmonella within those lymph nodes now gets ground up and is a part of that ground product. So then for consumers who might enjoy a hamburger that is less than well done or cooked to 160 Fahrenheit, could potentially be at risk for salmonella in that hamburger, potentially from a contaminated lymph node. Now, I also do want to point out that those that salmonella is within a lymph node, and that lymph node is embedded within the fatty tissue of the carcass. So if we were doing a carcass wash at the abattoir, let's say hot water, or lactic acid, for example, those washes do help reduce pathogens on the carcass. However, if salmonella is embedded in the lymph node, and in the fatty tissue, of course, it's protected from those interventions. And so that makes it very difficult to protect against any salmonella entering the horse through the lymph nodes. So we have to really then think about, what can we do in at the live animal side? So pre harvest to reduce the chances of having someone else in the lymph nodes? Also, can we remove lymph nodes? That's been a question. Animals have hundreds of lymph nodes throughout their bodies, right? So it would be very, very challenging to get every lymph node removed from every carcass. And so some studies have looked at what if we just remove maybe the biggest six, right? So some are bigger than others, right? Some, if they are contaminated and contaminated at a high concentration could in theory, be providing a larger load of salmonella into the ground product, then a teeny, tiny lymph node that maybe isn't as contaminated, for example. So it's really kind of hard to predict and know which lymph node might be contaminated? And, and really, what's the best way to approach this from an intervention and a food safety perspective, but it's a very important area of research currently.

 

Yeah, that is really fascinating. Sarah, and the way that you explain it is really helpful in understanding the implications for the consumer. I'm just curious about salmonella, who knew that salmonella hang out in lymph nodes is the same? Could you talk just a little bit about the physiology? And maybe that will allow you then to get into some of your findings in terms of what can we do pre harvest? Is it? Are there particular kinds of rations that help reduce the amount of salmonella? So first, I'm wondering, is it just a natural part of the physiology of the animal? And what have you learned about ways to reduce it pre harvest?

 

Yeah, great question. So I will kind of start, I guess, by how salmonella even ends up in the lymph nodes and kind of talk through some of those points. So salmonella is oftentimes naturally in the gastrointestinal tract of cattle. And in most cases, cat cattle are not clinically ill if salmonella. Now we have over 2500 Different serotypes of salmonella, and not all salmonella behave the same way in every post, if you will. Now, what might make us sick, like a salmonella Newport, for example, might not cause any issues in cattle. And so it's really hard to pick up at the feed yard level because that you might walk through the pens and think oh, well if they're that contaminated with salmonella, they should be ill and I can pull them and treat them it'll be fine. That's that's just not how it works because cattle are not as susceptible to salmonella. As humans are. In general, right. There are some serotypes like salmonella, Dublin, that can cause clinical illness in cattle. So I'm speaking more in general terms that cattle generally do not get sick. And so they harbor it in their gastrointestinal tracts they pay In their feces, their feces end up in their pins, and cattle lay down, it gets muddy and wet, and so it gets on their hides. And so salmonella is very much in their environment as well. So when we think about that situation with cattle, if it's in their environment, and if it's in their GI tract, it's possible that it's also finding its way to the lymph nodes. And there's a couple of different ways to consider that. One is through the gastrointestinal tract. So salmonella can pass through actually the lining of the GI tract.

 

They can utilize what are called the M cells of peyres, patches in Peyer's patches are essentially like immune tissue in the GI tract. And someone will actually utilize that to pass through. And so then they can enter into the bloodstream and also be drained to the lymphatic system. Oftentimes, they're in Gulten in a macrophage or some sort of immune cell. And then those immune cells might carry the salmonella to the lymph node. And then we don't really know what happens after that. One of the problems with salmonella in lymph node research is if we're getting these from animals at the abattoir, so they've already been euthanized and are hanging on the line. I have that one shot. So if I wanted to sample cattle throughout it's, it's I can't just get a lymph node from a live animal, right? I have to get it at death's. And so it's not like I can sample the same animal throughout its lifetime to see when that lymph node became positive, and did it stay positive? And did it ever go negative? So those are some of the questions we have in terms of what salmonella finds its way to the lymph node through the GI tract, for example, how long is it positive? We don't know? Does it get cleared at some point does it pass through that lymph node to another lymph node, for example. And there's some research that's kind of looked at that but we still need some more effort there to kind of identify, but again, challenging research. Now there are some other ways that we sort of hypothesize that salmonella finds its way to the lymph nodes. Now, some of those peripheral lymph nodes that I mentioned, one that I have researched, and a lot of others have particularly is called the sub iliac lymph node. Now, the subiliac is a larger lymph node that kind of sits on the hind hip of the hind leg of the animal, and it drains the hind leg in that region. So we were always scratching our head. Why is that lymph node positive? How did why is the hind leg contaminated with salmonella that lymph node perceived it right? So there are some questions about is it an abrasion, that salmonella is entering through and then gets filtered to the resident lymph node, maybe it's biting flies, we know that flies love to hover on feces, right. And so maybe they're hovering on the feces and then they go bite the hind leg of the animal and introduce salmonella transdermally. And then it finds its way to the lymph node. Now, there has been some research done by some of my colleagues that have looked at what happens if we actually do transdermally introduce salmonella at different points throughout the body. And there's been really interesting research trying to understand where salmonella ends up if it's introduced transdermally. And it does tend to be in kind of the surrounding lymph nodes in that area. So that helps us kind of understand how it can happen not just through the GI tract. Now, it is though, like the sub iliac lymph node on that hind leg, for example, that can probably find its way into the ground beef system B just because of its location and adipose tissue, and then that adipose tissue goes to ground beef. So what do we do about this? Right? Well, we're still trying to identify what to do about it actually. So if we go to the farm level, we need to try to minimize salmonella in the environments and in these animals as well. Now, I will say that generally there are trends to when we find salmonella in cattle lymph nodes as well as in cattle feces and the general trend is it peaks in sort of summer to fall As you go south in the United States, and then we've also done some studies in Mexico, I think one study was, I think, September in Mexico, and we had extremely high salmonella prevalence. But you know, we were going south. And we were at that peak prevalence time. So, in general, salmonella is not found as often in lymph nodes or in cattle feces at other times of the year, and especially like here in the Midwest, we don't find salmonella as much as we would as we move south.

 

So that helps us also sort of target some of our efforts in terms of where do we think the biggest risks are? How do we help those feed yards or those avatars and then, you know, we can apply it to all regions as well to just help minimize any prevalence we have throughout the United States or throughout the world eventually, as well. So pre harvest, good, you know, good management practices, trying to help keep salmonella out of the environment, cleaning, water troughs, and so forth. But also, as you mentioned, what are we feeding the animals? And so we have actually looked at different studies where if we add a supplement, for example, like a probiotic, does it help reduce salmonella in perhaps their feces in their environment? And then of course, in the lymph nodes as well. So that is a pretty important area of research in terms of what can we get that we can feed to the animals that will not, of course, be harmful? Right? It has to be, it has to have animal welfare in mind, but also productivity, right, we don't, we don't want to also reduce their effectiveness in terms of their growth and what they're already consuming for their diet. So we have to work with like ruminant nutritionists and feed yard experts to help identify things that might work, things that could be beneficial without harming the cattle and their and their daily game in their productivity, while also trying to improve food safety. And so it's kind of a balancing act there and definitely an interdisciplinary effort to try to tack this issue. And then I mentioned, of course, you know, at the avatar, there are questions about, should we be removing some lymph nodes? What if we remove some of the bigger ones? Does that reduce the amount going into the grind, and then in our ground beef product? So we're still trying to figure all of those things out, but it's a Farm to Fork question.

 

That's fascinating, because it really has shows how little, you know, toward any sort of, I don't want to say global because that's not what I'm implying. But you don't have a method for for really positive controls the moment it appears. Right.

 

Right. Well, I mean, I will say, you know, the industry is doing the best they can, right? Oh, sure. Healthy cattle with clean sanitary environment. But yeah, we haven't quite found the magic bullet or the silver bullet, if you will, to address this issue. And I think some of us that have worked in the pre harvest space, kind of get frustrated with the salmonella problem, because salmonella just won't go away. It's and you know, when you think about salmonella from an overall public health perspective, it just won't go away. So like the Healthy People, 2010 and the 2020. And you know, now we're getting ready to hear about 2030 for salmonella. We aren't making much progress towards those. And there's a lot of effort going on to try to address this issue. Because salmonella is problematic. And we're doing what we can. We just haven't quite found the solution yet, in general.

 

Are any particular breeds or subtypes of in this case, cattle or swine? More or less? I don't want to say resistant because that imply something we don't know. Are they more or less likely to be hosts for salmonella?

 

That's a very good question. So I will say from the lymph node perspective, one of my projects that I worked on during my PhD work at Texas Tech, actually compared what we would call feedlot cattle are fed cattle to what are called Cole cattle. So cattle that maybe were like old breeding stock that were done being used in that way and then you know, sent to the avatar. So, oh, feedlot cattle versus other cattle, if you will, or cold cattle was one of our primary objectives. And what we determined there is that feedlot cattle are far more contaminated with salmonella in their lymph nodes than coal animals. And now when you think about it, I kind of describe the feed yard environment, right, we have animals and pins together, and some may have salmonella, and maybe at high levels and others might not. And then they're hanging out together. They're eating out of the same bins, and drinking out of the same water troughs. And so that kind of explains, I think, why some of our feedlot cattle are going to be more contaminated, particularly as we move south and in the summer and fall, then our cover

 

Is the contamination from the lymph nodes in ground beef, the major contamination point, or what are the other? What are the other major areas that contamination could occur? I guess that's kind of a two question. Question. Yeah.

 

That's a great question. So part of what prompted the lymph node research, you know, a decade ago, I guess, really is when we kind of got into this business, if you will, is, you know, we, we have these carcass washes that are pretty effective at reducing salmonella on the carcass. So we might have a certain prevalence or concentration, pre wash, and then it's hard to find salmonella carcasses post wash. But then when we grind up the carcass, salmonella's there, so what gives? Right, why, how is this possible? And so then started asking the question of what all is actually going into the grind? Right? And, well, it's not just lean tissue. And it's not just that oppose, there's lymph nodes in there, too. And so that kind of prompted some of that question. So to answer your question, I would say yes, we know lymph nodes can be a source of contamination. If any salmonella is remaining on the carcass, post intervention, or if it's cross contaminated after for example, during fabrication without clean and sanitary environment, and personnel working to protect against that, then, you know, potentially pathogens could be introduced, post washing of the carcass as well. So a sanitary environment sanitary tools, trained personnel. But we also have to remember that if we are using a carcass wash like hot water or lactic acid, for example, we have to use it properly, right? It has to be at the right temperature, and it has to be mixed to the right concentration, because all of those things help to reduce salmonella on carcasses if salmonella is there in the first place. And so there are a lot of different ways I guess that salmonella might find its way in. But we are particularly interested in understanding the role that the lymph nodes specifically plays. And hopefully we're going to be looking at that very soon as well.

 

Great, thanks.

 

Sure, you have other things you'd like to talk about other than salmonella, but we're obviously really interested in the nose, they're going back to the consumer end on Maureen’s question. I was wondering about the effects of salmonella, you know, my awareness of food poisoning, or borne illnesses through beef sort of started 30 years ago with E coli, which of course, have very different mortality kinds of consequences. I'm wondering how sick the cells make people and how big of a problem is this for our country in general? 

 

Very, that's a great question. So you brought up the ShiGa toxin producing Escherichia coli. Right, and, as we call them, are definitely very concerning from a public health perspective if they're present. Right. So salmonella. It's, you asked a sort of a loaded question with salmonella. You know, when you think about how there's over 2500 serotypes right? Not all of them are going to behave the same way. And so I'll comment on that a little bit more here in a minute. But what I will say is that salmonella has oftentimes been associated with the number one cause of death for foodborne illness. So that's a problem and salmonella can make a lot of people sick and it can make some people not very sick, right and so people do die from salmonella. And you know, we generally the classic gastrointestinal illness, right it are the symptoms and salmonella can last you know, three to seven days. Sometimes it can last longer than the 24 or 48 hour bug but you might kind of think is the general foodborne illness. And it can cause some issues especially in immunocompromised individuals like it can also lead to like septicemia for example, but in general, healthy immune competent individuals, stay home stay hydrated. And generally it can have in a few days or you know, a day or 234. And you might not, you know, even consider going to the doctor or the hospital just depending it really kind of varies, but a lot of that can depend upon not just your immune status, but what serotype you were infected with and at what level. So, some salmonella serotypes that you hear about in the news potentially associated with outbreaks like salmonella Newports Salmonella enteritidis salmonella typhimurium, some of those you may have heard about and associate with foodborne illness. So those are some of our most clinically associated serotypes, if you will. So for whatever reason, and some research is looking into this, they are more virulent for humans and can cause more severe illness. Not just that, but at a lower dose as well. So some outbreaks have shown that those more clinical serotypes might be around 10 100 cells versus some other serotype outbreaks have been around a million cells or more. And so it really can depend on a lot of different things with salmonella. Now I will say this interestingly, when I was doing my research at Texas Tech on lymph nodes and salmonella in lymph nodes, when I was working with the Meat Animal research center and Clay Center, Nebraska, Dr. Dana Hart high up there she was serotyping our isolates. And the majority of the serotypes that we found were Montevideo and a Anatum. And Montevideo and anatum aren't generally associated with being highly virulent, or having a lower infectious dose. To be clear, we found all types of serotypes right, we found a quite a variety, including some type of Miriam's and Newports. So it's, even though Montevideo and Anatum were the we're the largest, it doesn't mean that there is no risk associated with them. But it is interesting, though, that some of the ground beef data in terms of salmonella serotypes from the United States Department of Agriculture, Food Safety Inspection Service, in past years, has shown a higher prevalence of Montevideo and an Anatum as some of the stereotypes. Now we do know that Montevideo Anatum are often associated with cattle, we often find them in our cattle studies. But the fact that we found them also in our lymph nodes, and we know lymph nodes go into ground beef. And we know that ground beef sometimes has Montevideo in an autumn at a higher prevalence. I don't think that's a coincidence, either. But I haven't investigated that that's just my personal hypothesis and trying to make connections, if you will, to all the data that's out there.

 

Yes. Which gears just a bit, looking over some of the activities that you're involved with on campus. Um, you are also affiliated with the Center for Food Safety Research and Child Nutrition, which I think is in college years. Program is and what your involvement is with it.

 

Right. Absolutely. So I work with my great colleagues over there. Dr. Kevin Roberts, Dr. Kevin Sauer, Dr. Powell, Paula Pious, excuse me, and some others that have been fantastic colleagues and collaborators. So that center is aimed at addressing the need for like school, school lunch programs, for example, and child nutrition programs in general. And so they have as part of their center different funding. Research projects, oftentimes is a micro lab study. I'm involved with some of those studies. And so we have a good time trying to address some of the questions out there and they're a great team to work with. So what we've done in the past is looking at cooling of large quantities of food. So as you can imagine in a school lunch program, It's kind of hard to know how much food you're going to need from day to day. And so at the end of the day, I might be left with several large pans of chili, for example, why don't want to just throw that out? So how do I cool it properly so that I don't have a risk of foodborne illness for the students.

 

So there's something called the temperature danger zone, which is the temperature where bacteria can grow more readily in a food product. And some sources would say it's 40 to 140. Fahrenheit, some would say it's 41 to 135, I tend to say it's the 4140 rule, because I think it's easy to remember. So if a food product is held in that temperature danger zone for too long, and if there are bacteria present, they can grow. And depending upon the bacteria, it could make a toxin that could make you sick, right? Or it could grow to a high enough level that the actual bacteria might make you sick, depending upon what the bacteria itself is. So we need to make sure that we're providing resources to schools on how to cool properly when you have large portions of chili or rice or tomato sauce, for example. So we've worked together to address some of those questions, looking at different cooling techniques. Do we cover it? Do we not? Do we cover it a little bit? Do we put the pans in ice water? And then in the fridge? Do we just put them in the fridge. And so we've looked at a variety of different food products to help try to address some of those questions. And then another study that we did was looking at food served away from school on a field trip. So a lot of schools might provide sack lunches to students. Well, when two field trips start, right, usually we leave at 8am. Everybody gets on the bus and we go you know, visiting outside looking at different things while the lunches stay on the bus probably. What's going on with those lunches? Are they properly packed with ice or ice packs in insulated coolers? Sometimes these field trips might happen in a situation where it's a very hot day. And we all know how hot our cars can be at the end of a hot day. You think about what a bus might be on a hot day. So we tried to answer the question of if a sack lunch is take bank being taken for students on field trips, how are they being stored and how safe is it? So the FDA Food Code has what's called time as a public health control. So we can consider for hours as the public health control if like temperature controls not available, for example, it's called time as a public health control. Well, we need to answer the question is that effective in a scenario where maybe a sack lunch is not receiving proper storage conditions for refrigeration, and maybe it's on a hot bus for three or four hours. So we worked on a study trying to simulate what those bus temperatures might be. So worked with school officials around the country since of temperature data loggers in the month of May in June, I think it was to North Carolina, and Arkansas maybe and ask them to put these temperature data loggers in a bus and outside of a bus. And we tried to look at that sort of 7am to noon or one timeframe to see what the temperatures were doing to know what the risks might be for a cooler of sack lunches on a bus. Well then we tried to create a worst case scenario. So we took that information and then made it worse right temperature wise. And so we created a program on a smokehouse and ramped up the temperatures like what might happen on a bus on a hot day. And again, exaggerated right? Let's stress the system as much as we can to create a worst case scenario and then prepared sack lunches that had salmonella or Listeria monocytogenes inoculated on them and had temperature probes and different sack lunches throughout the cooler and tried to determine not just what's the temperature doing in those coolers and in those sack lunches, but did salmonella or listeria grow. And we had determined based upon preliminary studies that a cooler packing scenario with no ice or With ice, one layer on the bottom or worst case scenario, so those are what we also used in our study. And we determined that the pathogens did not grow during that four hour four to five hour time frame.

And so we determine there's pretty low risk in one of those scenarios of the pathogens being a problem in terms of growth. But of course, there's a huge caution there, right, we looked at salmonella, and we looked at listeria, and we only looked at turkey sandwiches, carrots, and apple slices. There are other pathogens, and there are other food products and their other different formulations of turkey sandwiches and stuff. So we still recommend not keeping it on a hot bus and having at least one layer of ice and eating, of course, within the four hours with food code recommending only four hours as the time point for public health control. So that's a little bit of a summary there. And I have to acknowledge to that Dr. Phoebus, was associated with those studies also. And so our food safety team, as a whole has worked with this group. So it's been a it's been a different approach to research than, you know, the cattle and the lymph nodes and things I've been talking about. And so it's been a very interesting experience that I've enjoyed learning about as well.

 

Did anybody ask you what you found in food science is a discipline that got you so hooked on it or was not there for other sources of scientific disciplines?

 

That's a great question. I think it's, you know, I really like pipettes, and I really like the benchtop. And I really enjoy getting to take a meat sample or a spinach sample or something and do different micro techniques that in a day or two, I can see E coli or salmonella on a petri dish, and I can count it and what can I do to treat that product to have less salmonella on the next time that I count? Right? That's fascinating to me. But we'll be what I'm really hooked on is the importance aspect, I really appreciate that what I do could impact lives. And if I can find some sort of solution to a problem, that might reduce salmonella in the food supply. And that's fewer people that get Salmonellosis and fewer people that might have serious illness or die from it, then my job is, it's definitely worth it right. And I feel like I've made a positive contribution, not just to science or to the university, but to public health and to society. That's ultimately what I want to do.

 

That's very well thought out.

 

There, I've got a follow up to that your opening narrative about how you got into food science, you framed it as sort of chance and, you know, yes, there's a lot of chance and how we end up in our particular paths in life. But I can't help but notice that it wasn't just chance that you had this exposure to an academic who was a woman in food science, who sort of got you started. I wonder if you could reflect on your time as a graduate student and now your own time with your students in your lab? I wonder, do you have some opinions about what we should be doing to encourage women to choose and to persist in science?

 

Yeah, absolutely. So I actually am very appreciative that you brought this up, because it's always really important to me to acknowledge that I didn't get here by myself, I had tremendous opportunity, and mentors. And I had people take an interest in me in my professional development, and in my education from a very early age. And so and so I often say I don't know what I would be without Todd and Mindy Brashears I don't know because they introduced me to food science and you know, now my career and so I feel like I will always owe them so much gratitude. And I'm always wanting to make them proud. Because it's as if they hadn't provided like, I don't know where it would be so no, it's you can imagine how important it is to me to pay it forward. And so it I find probably some of my greatest satisfaction. Feeling like I have impacted a life like I have helped a student become a better scientist, help them to be grow in their professional development. maybe help them learn themselves and about life in general. And so if I can do that for one or two, or however many students like they have done for me, then I'll feel like my job is done. Because I think that investing in the future, the way they and others invested in me, is the key to having future scientists and, and having a safe food supply. And so for me, that's really you know, that at the end of the day, that's also what gets me the greatest satisfaction. So in terms of the women aspect, yes, I will say that, you're she has been a wonderful mentor to me, in terms of what it's like to be a working mom as well, and how to balance those things and still be successful. And I've learned so much from her from a personal perspective in that way, too, that, you know, we really need to enrich and encourage that in other women also, and in young ladies who might be interested. And so for me, you know, sometimes we have opportunities to work with different young lady groups that come through at K State. And those are the types of things I think, you know, I should be going to visit and sharing my story about how this woman invested in me at age 14, and look where I am. And she still mentors me today, right? I, you know, text her, often just, and we chat often. And she's still very much involved in my life. And so we need to start that with others at a young age and provide them mentors and role models and a path forward through STEM careers, so that we do continue to have young ladies interested in being the next generation.

 

Very well said, Thank you.

 

That is fascinating. That's a wonderful testament to what you are doing as a teacher, as an instructor at K State and having the students going through your program, what an opportunity for them.

 

Well, thank you. I mean, they do so much right, in terms of the research in helping to teach and training new students that are coming in. And so, you know, I think graduate students and undergraduate student workers are also somewhat of the unsung heroes, right? You know, I did a lot of the lymph node work myself, so I can talk about it. But I also get to talk about the lymph node work my students are doing today. And so you can't forget to acknowledge how important it is to not just recognize what they do and their success and how important they are, but also recognize their contribution to science and how important it is to keep fostering that so that we have great scientists coming out to carry the torch in future generations as well.

 

I would like to ask you if you've got any final comments or any questions of us.

 

You know, this has been a wonderful time. I really enjoyed talking with you about my research and kind of about who I am today and how I got to this point, and I really appreciate the opportunity and thank you for all the very insightful questions and hope that we can maybe do it again sometime. Thank you so much.

 

If you have any questions or comments you would like to share check out our website at https://www.k-state.edu/research/global-food/ and drop us an email.

Our music was adapted from Dr. Wayne Goins’s album Chronicles of Carmela. Special thanks to him for providing that to us. Something to Chew On is produced by the Office of Research Development at Kansas State University.