Hello and welcome to Cooking Issues. This is Dave Arnold, your host of Cooking Issues coming to you live from New Stand Studios, the Rockefeller Center. Joined as usual with Nastasia of the Hammer Lopez. How are you doing? Good.
We got uh John. John in the booth. How are you doing? Doing great. We got uh where Jackie Molecules, where are you?
Where are you right now? I'm in DC now. DC. Jeez, man. What's up, Globe Hopper?
You're just like everywhere. You're like a like a like globe hot trucking trotting engineer. Yeah. And of course. Yeah.
And of course, working the panels, Joe Hazen. How are you doing? How are you doing? Doing all right. Uh, and for those of you who are listening live on Patreon, call in your questions to 917-410-1507.
That's 917-410-1507. And I anticipate you might get some calls in because today we have a very special guest, uh, Professor Don Shaffner, who is the extension specialist in food science and distinguished professor at Rutgers, uh, host of the podcast. The podcast is called Risky or Not, correct? That is correct. Risky or not, which is a good, which is like a good thing because it's not like completely safe or not.
It's risky or not. In other words, like, eh, should I do this or should I not do this, right? Exactly. That's the premise of the show. Yeah.
Uh and we'll get into that in in a in in a little bit. And uh on the uh Twitters, you go as Bug Counter. Now, let me ask you a question. Do you legitimately like sit around and do counts all day? No, I have graduate students for that.
So you're more like bug counter overlord. Well, so so here's the thing. So I I describe myself as a quantitative food microbiologist, and I ascribe uh to the the uh adage when you can count. And so I do I do like quantitative data, and so we work with microorganisms, and so uh bug counter became my my name on Twitter. I do want to say for the record, um I don't count uh nobody in my lab counts insect parts, and and so I'm using bug there in the colloquial, you know, as microbiologists refer to the organisms we study as bugs, but not actual literal entomological bugs.
So you're not at all worried about like number of cockroach legs in my in my flower, for instance. Well, I I'm you know, cockroach legs won't hurt you. Uh it's the it's the microorganisms on the cockroach legs that will hurt you. And so uh yeah, it's gross, it's disgusting to have cockroach legs in your flower, but uh but the cockroach legs, you know, they're not they're not big enough to actually stick in your throat and hurt you. I mean, that seems a little bit like uh guns don't kill people kind of an argument.
Is not the cockroach legs per se. It's the fact that they walked through poop before they showed up in your food. Well, let's see, like to not to stretch the gun analogy, but if you had a gun without bullets, I guess you could throw some throw it at somebody, right? Uh, you know, so I mean it's it if you have it's sterile cockroach legs, you know, it's gross, but sterile cockroach legs uh don't kill you. It's it's uh it's the microorganisms.
All right, but before I get into the why I actually had you on, I'm curious about this. You know how back in the um in the early 1900s, right, when uh people were going through their first wave of getting really, really worried about kind of germs and insects and whatnot. And everyone was like, oh my god, flies, fly, oh my god, right? But flies legitimately do land in filth and then land on your food, right? I want to make a t-shirt for flies that says, My last, you know, my last uh resting place was poop.
You know what I mean? So they can wear so when they land on your food, they can wear a t-shirt, I was just in poo. Right? I mean, like, that's kind of true, right? But there's how much actual spread is there via fly?
Well, this is a really good question. And it's actually a topic that that has come up before on risky or not. And and the so when you think about it, again, as a quantitative microbiologist, uh, you know, uh and and as somebody who does risk assessment, there's a expression in toxicology. The dose makes the poison, and and the same sort of thing applies to microbiology as well. And so, yes, flies can theoretically spread germs, but uh the what you have to say, you have to consider is well, where was the fly last?
Okay, did they walk on poop? Did they get some let's say salmonella on their feet? And then did those salmonella then transfer to the food? And were the levels sufficiently high such that you have a reasonable probability of illness? Or or or is would would any salmonella transfer?
And so, you know, certainly I don't advocate eating food on which flies have walked, but the actual risk from a single fly landing once on your food before you you brush it away, that's probably a pretty small risk based on all of the available scientific information, which admittedly is not is not a lot. So you're cool with it. Well, here's the thing the name of the show is not cool with it or not, right? The name of the show is risky or not. So uh it's gross.
Uh I don't advocate, again, I don't advocate flies walking on food. I certainly, if I have a choice to have flies not walk on my food, I will definitely choose that. But uh, but from from a risk perspective, again, the the chance of illness from a single fly landing on a food once, I'm gonna say that's a pretty small risk. So but but that's that's different from I'm cool with it. All right, all right.
So in other words, you're like, would rather it not happen, but you're still gonna eat it. Uh well, uh, you know, that's a good question. I mean, I don't I don't have a uh I don't have a food in front of me that a fly has just landed on to be able to definitively say whether I would or not. Um yeah, I don't yeah, it's it's and that's a different question. Like, would Don eat it or not?
That's again, that's yet another different podcast. And we gotta start that show. We gotta get that show. Like uh Nastasi and I will create various levels of gross and hand them to you and be like, did he eat it? Well, just you don't even have to say anything.
It's just we have the camera on you, and then like an hour later we'll look. And if you took a bite out of it, it was fine. You know what I mean? Or you decided to eat it. Uh just an idea for you.
You don't have to do it with us. That that that idea is yours. Yeah. And well, and here's the thing, we should also have like a revisiting, like come back 24, 48, 72 hours and see if I had any consequences from eating it, right? Because that's the important, that's the important thing.
Oh, you know what? Before we even get into what I want to, let's talk about this because this is a big deal for all human beings everywhere. It is my feeling, and you tell me because I'm happy to be wrong about this, that nine times out of ten, people have no idea where they got their food poisoning from, but they think they do. And so they blame X, Y, or Z thing, but they're very often wrong because they don't really have the incubation periods right. You want to talk about this at all, whether I'm wrong or whether what you think about it.
No, no, I think you you you actually I really appreciate you raising this this point. So very often people will think it's the last food they ate, um, which for certain types of of uh foodborne disease might be true, but for many types of foodborne disease, it's absolutely not true. And it's more likely something that you ate 24 hours ago, 48 hours ago, even as much as you know, uh uh 72 hours ago, three days ago. And so yeah, people will very often get that wrong for sure. Yeah, and is it the salad that kill you nine times out of ten?
Is it the salad? Oh, it depends. It really depends. I mean, we we are in we are in the risky salad season. If you look historically at when people get sick from eating leafy greens, uh often it is around this time of year.
And so it is uh there is some some potential risk. But it might be salad, it might be, it might be you know, meat that was cross-contaminated, it might be undercooked meat, it might be food that was left out of temperature control for too long. But the problem, the problem with microorganisms, you know, when it comes to food is that they're they're so diverse and there's so many different ways they can cause illness. So it's it's difficult to generalize and say, oh, yeah, yeah, it's the salad, because sometimes it might be the salad, but sometimes it might not be. I did not know that there was a risky salad season, but now I'm kind of grooving on the idea of a risky salad season.
When is Dr. Don, when is the risky salad season? Well, it's roughly this time of year. So it's it's roughly in the in the in the fall, like I would say September, October, um, uh, you know, that time frame. But but again, that doesn't mean that other it's like it's like when you eat shellfish, right?
In in months, uh months you're only supposed to eat shellfish in months with an R, right? Uh but but it's so it's not it's not it's not a definitive indication of risk. But if you if you look at the uh outbreaks and you look at big outbreaks linked to leafy greens in particular, it they do tend to happen around this time of year. But again, that's not it's again like so many scientific things in in life, it's it's there's it's not hard and fast. It's only uh uh you know a general a general statement.
Is that just a known correlation or is there a theoretical is there a positive cause for that? Well, we you know, in many cases we we cannot trace the the uh the cause back to a specific incident. We what we do know, and again, this is talking specifically about leafy greens in this country. And so the leafy green industry, the way that it works is they they start in California and then uh as the as the season progresses, they move gradually south uh and and and end the season in in uh Yuma, Arizona. And so we are in that period now where we're in transition from California to Arizona, and we don't know we don't know what it is about that transition period that might lead to uh that might lead to outbreaks, but it but it is something that a number of people have observed, but we still haven't quite figured it out.
Obviously, if we figured it out, the industry would be fixing that problem and and we wouldn't we wouldn't have this. But so for now it's only uh it's only uh you know a general idea, like I said. First of all, I feel like you're calling out Arizona. I just feel like I feel like you're like throwing some serious shade on Arizona right now. Well, it well, it might it might not be, it might not be arriving in Arizona, it might be aspects of leaving California, right?
It might be aspects of packing up the operations, you know, uh and leaving California. And so let's let's not let's let's let's let's throw equal shade on on uh both Terrizones. Well, you're saying everybody will be bad. That's not that Arizona is bad, it's just California has some salubrious effect on the on the greens to get rid of the what what's the what's the pathogen of interest here? Are you first of all, are we talking about Romaine?
Because it's always romaine that they that they they they burn, right? That they they sweep off of the shelves, at least here in New York, and then burn. Is that what we're talking about it it is it is often romaine but again one one point that I want to make is that part of the reason why romaine may cause a lot of outbreaks is we just eat a lot of romaine right and so it it may it may not be that romaine per se is risky it may just be that that that's just the predominant leafy green that we eat right and we do we do know uh that that it it may well be that these packaged salads are riskier just because of the way that they are uh prepared you know the the the lettuce is harvested the the lettuce is chopped up it's washed um and so you're if you have contamination that may spread the contamination over multiple servings and then also when you when you chop off that lettuce uh that may lead to places where the harborage points for the bacteria whereas if you leave the lettuce whole as as head lettuce the contamination may be confined to a single head and potentially there's less cut edges of the leafy greens to allow the bacteria to attach and and and maybe to grow. Now once you get your your uh your your whatever pathogen of interest into your lettuce it can no longer be washed off the surface right like once it's been hacked up and it's grown into the lettuce like pretty much that's it right you you may be able to wash some of it off but it's certainly the best thing to do is prevention right the best thing to do is keep it from getting there in the first place. Because once it's there, yes, you're right it's it's very difficult to to remove and again this part of part of what we're trying to do here when we're washing is we're using sanitizers in that washwater so that if you do get uh let's say some pathogens that are on one leaf uh they don't go into the washwater and then cross contaminate to another leaf like by using sanitizers in that wash water you stop that you stop that spread but if it does if it does spread then yeah you you it it's gonna be really tough to do anything about that.
What are your thoughts on uh you get the bag and they say it's pre-washed but uh it's already turning into its own filth inside of the bag and like clearly like slimy and garbage and your son is like it's that's just already washed and I'm like no either you wash it and it like or you throw it away this is filth. No? I mean this idea that you can wash it once and forget it is crazy right well my my my sons have been trained not to have that conversation they they don't live with me but uh they're they're grown they're grown young men but no what I will say so if there's a there's a scientific report out there that says that basically in the opinion of experts once the lettuce is been triple washed and it's placed in a bag there's very little additional washing that the consumer is going to be able to do to have any positive benefit. And in fact it might you might actually increase the risk if you don't have good sanitary practices in your kitchen. And so um the the general advice is you don't need to wash pre-washed lettuce because the the either the risk is not there and you're gonna be fine or uh the risk is there and there's not much you can do about it.
But now the other point that you made about things looking gross or slimy or being past their their their best buy date I'm I'm pretty particular about and we do buy bagged lettuce in in my house and I'm pretty particular about how it looks and and so if I do start to see I'll pick out the slimy pieces and if it starts to look too slimy, I'll just I'll just pitch it and say we just need to go to the store and and get more. Because I mean again, it's not the slime that makes you sick, but that slime is an indication that maybe that lettuce has been mishandled or temperature abused or or just you know physically you know beat up to the to the extent that it allows heartridge points for the bacteria in places where they can grow. It's always it's always the arugula, it's always the arugula, it goes slimy and smells like an aquarium. Terrible. You know, that's that's funny.
I've I find the opposite. I find that arugula for whatever reason is is pretty is pretty robust. Whereas the uh the romaine and the spinach, uh at least in my house that tend to go so bad uh before the arugula. But uh, you know, but that's just my experience. The spinach started bad.
That's the problem. The spinach started out as bad. You should be cooking that. You know what I mean? Like uh you know, yeah, I I'm not a I'm not a fan of raw raw spinach.
Yeah, that's a good point. They're like, but if the spinach is real, real tiny, you can eat it raw. Okay, or you could just let the spinach get big, hack it up, cook it with like in a cream sauce, make sure you squeeze out all the nasty like filth water, not because it's unsafe, it's just because it's filth water. You know what I'm saying? Anyway, I look, I don't know what happened.
At some point in my in my 30s, everyone started eating all of these formerly cooked greens raw. And I'm like, why? Like, why would I ever eat kale raw? Why why would I do that? Well, I mean, I'm I'm old enough to remember that what what you bought kale for was to put on the salad bar over the ice, right?
It was decorative. You nobody ate it. Yeah, nobody. I mean, I had a rabbit. Rabbit would eat it.
You know what I mean? But like, or you know, kale makes a decent cooked green. I mean, it's no charred. It's no uh, you know, it's it's no collared, you know what I mean? It's not even at the level of an escarole.
You know what I mean? But it's uh, you know, I mean, I shouldn't say that escrow's great. I don't know why, I don't know why I suddenly put Escarole next to kale. Escarole is delicious. I grew up eating cooked escarol, you know what I mean?
Um anyway, all right. Uh what about this? What about people before I get off these uh bagged greens? What about people who believe, and this is also meats and veg, uh, who believe that by somehow buying and you alluded to this by saying, you know, if I'm chumming up, you know, eight tons of romaine and putting them into a giant vat, and then I F up somehow and put them in a bag, now I have eight tons of romaine that have been effed up by one bad head, right? That you kind of intimated that, right?
It's the same argument. Yeah, I don't think the industry calls it chumming, but that's a good word. Yeah, yeah. Well, and it's the same argument with ground beef, right? Like you you take uh you take uh infinity cows, you grind them all together, and if one of those cows was bad, now the whole batch is like, you know, it's the one rotten apple kind of a situation, right?
And well, I I think with I think with ground beef it's a little bit different, but we can come back to that. Right. Well, so now people have taken that argument and then they believe somehow that they are safer buying uh quote unquote farmers market or organic products, even though in a supermarket organic product has been there for eight billion years just because of turnover is so slow, at least it used to be, you know, if you're not shopping at a specifically place that only sells organic stuff. Uh so what do you think what what what do you think about people who believe that they're uh trying to dodge a uh a safety bullet by going that way? Well, you know, there's there's not a ton of research on organic versus conventionally grown food, but the research that's out there shows that either the risk is equivalent or that the risk might actually be higher with organic, just because of some of the growing practices, you know, increased use of manure, you know, things, you know, things like that.
And so uh but but it's but the again, that there's very limited research, and so it's by no means definitive. But but I think if you're if you're buying organic because you think it is safer with respect to bacteria, that's probably not a true true assumption. Now, you know, and again, the tests for pesticides on our organic versus conventional show that overwhelmingly um, you know, the food that we eat in this country is is free of pesticides. And so there's there's very little difference there as well. So if you're I mean, I think a lot of people buy organic just like a as a feel-good thing.
And certainly farmers can charge a higher price. And so if you want to give the farmers more money, I'm I'm all in favor of you know, paying paying farmers more. So that that's a good thing. But the I think that the the effect of organic versus conventional on risk is equivocal at best. All right.
Uh and you know, well, we'll take the pushback later on that. We'll just take the pushback later. We'll leave it and we'll take the pushback later. Uh so another reason I really wanted to have you on is because you know, your particular attitude, which I've noticed on Twitter, which uh which I enjoy, and wanted maybe to talk a little bit about the adversarial relationship that kind of develops between cooks and food safety people. Uh and you know, I think it's it's real.
I know you're not like people who I know who have uh been involved in writing some of the codes who I've talked to over the years, like meat scientists and you know safety scientists, they're really into kind of bulletproofing everything. And I know that a lot of chefs feel hamstrung by a lot of the rules that we we have uh to cook by that we know are inherently inaccurate, that are that are basically overkill, right? So I'm specifically talking about certain classic fermentation practices that weren't you uh uh available to us in restaurants for a long time, you know, we would get shut down or certain low temperature practices uh which you know were not available to us because they didn't meet the old quote unquote food code and this kind of big adversarial relationship has developed. I wonder whether you want to talk about that. Yeah so it's it's a I guess is one of my favorite topics to talk about and so it's it's tough right because on the one hand you have the chefs that really pretty much want to do anything.
You have the code which is written um by well it's written by scientists and lawyers and the and because what what we have to do in a code is we have to create bright lines that say thou shalt not cross this line right and then you have scientists like me who are like well it's really more of a fuzzy line and it's complicated and it depends and there's levels of risk. And so yeah it ends up being a really interesting conversation. But what one thing I am really interested in doing is pushing back on regulatory types who say no, thou shalt not cross this line and then having the debate about well okay so tell me tell me exactly how you decided to draw that line and why did you draw it there and what are the factors that you considered and what are what are some other mitigating factors that we could that we could use to maybe draw that line in a different place or hey you know the logic that you used to use to draw this line means that we should also draw this other line over here and try to use that logic and argument in a way that maybe gives the the chefs some more freedom or or figure out is that line even in the right place, right? Is the science that that that line is based on uh is that science outdated, or could we could we take a different approach to try to give chefs more flexibility in terms of what they do? And and then also realize, I mean, there's already flexibility, right?
You can already go and eat uh sushi. You can already go and eat, you know, this there's jokes, there's jokes going back years and years about sunny side up eggs in in New Jersey, right? Um, you know, because we and you can you can have them. You can you can you can have sunny side up eggs, even though there is a risk from that. And so I'm I'm more about like let's talk about the risk, let's let's inform people about the risk.
And again, I I know chefs don't like to have stuff like things on the menu that says if you order your if you order a sushi, you you might get food poisoning. I know that's that's probably not good, you know, marketing, but but from a uh education perspective, maybe that's the right that's the right solution. But yeah, I'm I'm what I yeah, I would I would like us to all be able to play nicely and have discussions about these things in in a logical way. It gives people choice. Consumers' choice gives chefs choice uh and and still tries to perfect public health as well.
I mean, the sushi thing is interesting because we all know that there's no way that a sushi restaurant in the real life can pass health code because they don't wear gloves. And I don't want them to wear gloves. You know what I mean? And and and and they don't wear gloves. Uh and so, you know, they have the the those things sitting out, they wipe down with the top.
I mean, there's not one thing that they do. You know, uh they have rice that's hardcore in the danger zone that that the health department has no way of testing the acidity of, right? You know, it clearly doesn't grow. By the way, do you also call it is it is it be serious? Because I always just call it like be serious, be serious!
Like what is it actually? Yeah, I make that same joke. Yeah, the full name of the organism is bacillus serious cereal. Right. And that's what's gonna happen.
If you leave rice out that hasn't been vinegared or sugared, right? You you have a a decent chance of probably not dying, although kids have died, right, from B serious growing in that thing, right? Right? Yeah, that that that's exactly right. It's again, not every bit of rice is contaminated, but I I like the way you phrase it.
You have a reasonable probability. We know uh that if you cook rice and then you leave it at room temperature or you cool it too slowly. Actually, I was just hearing about an outbreak where they cooled the rice too slowly, and actually somebody, an elderly person can die. So yeah, the silly cereus is generally not the kind of disease that that kills you. But guess what?
If you're in a weakened state, it for sure can can kill you. And that's why uh that's why we don't want to leave rice at room temperature for a long period of time. Except for, let's look at a sushi restaurant where that's their whole job. That's the whole business model. And so it's like these these folks aren't using gloves.
They're wiping things down with wet towels constantly, then like which you know, and you know that's not Sani's solution. And then uh they're uh they have room temperature rice sitting out for the whole service. So it's like, you know, and I I know that that there are things in place to make that safe, but it's not in the code. And there's no way that because there's it's not just the difference between you, the scientist, and the chef to the user, there's the code enforcement people as well. There's the there's you, then there's the code writer, then there's the code enforcer who has to have the knowledge, then the person who cooks, then the consumer.
It's like crazy, right? Yeah, yeah, yeah. Yeah, you're absolutely right. The person that writes the code is not the same person that enforces the code. But with sushi rice, uh that rice should, as you mentioned, it should be acidified, and that acidification process will allow you to keep at root keep it at room temperature and should uh prevent the the growth of bacillus cereal if it's been properly acidified.
Right. But then you know, have there been cases where people have tried to go more modern and cut down the acid uh to an extent where it's actually become unsafe? That's a good question. I don't know if that's the case. I know that we do we do continue to have food morning disease outbreaks from rice, but it is more the situation where it's a it's typically a Chinese restaurant um or or an Asian restaurant, and they prepare a big batch of rice and they just they just you know either cool it improperly or leave it at room temperature for long periods of time to make fried rice out of it.
And and and and the the nature of the bacillus food poisoning, there's one kind of bacillus food poisoning that comes from a toxin. And once that toxin is in the rice, no amount of frying or cooking will get rid of that molecule, that toxin molecule, which is what causes the uh the vomiting symptoms. And so uh, but I don't I don't know of any cases of improperly acidified sushi rice causing illness. Not that it doesn't happen, I just can't think of any examples of you know that that have that have come across my radar. So you know who's never going to poison anyone?
Jiro, he puts way too much freaking vinegar in his rice. I am sorry, those things are like crazy. But like, so you're saying it's probably doesn't take that much vinegar to actually do the trick. Plus there's sugar as well. So it's like it just doesn't take that much of a shift towards acid or towards a reduction of the water activity to have it not grow.
Well, and I'm not sure it's reduction of water activity, although it's interesting that you mentioned sugar. Um, I think it's more um, it's more the pH that's that's that's doing it, right? Uh, and it's the acidity and the and the pH. But but exactly how much you have to add and where that cut point is where you're because here's the thing: like you have a certain amount of acidity that will stop bacillus from growing, but then with a little bit less acidity, you might slow the growth. And so, yeah, I haven't I haven't really dug into the like the risk analysis of that to kind of figure out like where exactly how risky it is and where you can where you maybe you can you can edge a little closer to risk but still be quote unquote safe.
Yeah. Well remember, it's not is it safe? Is it's is it risky? Different question. Different question.
Uh life is risky. You know, me biking here today, I almost got killed. So there you go. Uh the there you go, yeah. You know what I mean?
Uh okay. So you bring us to an interesting point when you say that uh you know that there's this place where the B serious, and I can't call it anything but that, uh, where it's not that you are killing it, but it ain't growing. And I think the vast majority, a lot of the people who listen to this uh show do kind of sous vide low temperature work. And I think this is where this is where the safety rubber meets the food poisoning road, right? It's that there's all of this work that we do where it is true we're not necessarily causing something that started out life unsafe to be safe all of a sudden, but we are also not making it worse, right?
And I think that's where the majority of our low temperature work is actually taking place. I mean, the majority of us aren't actually pasteurizing the food that we're cooking. What do you think? Well, but I think we need to draw a distinction between the pathogen of choice or the the pathogen that's likely to be in rice versus in in meat, right? Bacillus or Plus Ridium botulinum, we want to control the growth because when they grow, they make toxin.
That and the levels of growth, at least with respect to bacillus, the levels of growth of multiplication of bacteria that you need to see before you get sufficient toxin formation to cause illness, that's different than salmonella, which is an infectious organism and which doesn't um doesn't have to grow to cause illness. Now, granted, I'd rather eat a single salmonella cell than a million salmonella cells, but realize that even the injection of a single salmonella cell has a probability of illness, right? So if I could, um, if you believe the math and the science, if I could get 300 people to volunteer today to eat one salmonella cell, chances are in 24 to 48 hours, one of those people, just due to the billiard ball luck of the salmonella cascading through their intestine, one of those people is going to be unlucky enough to be infected and maybe even develop symptoms and become sick. And so the the way that we're managing risk with rice is different than the way that we're managing risk with with let's say soupy cooking. But again, there's a lot more subtlety we can get into with cooking because it's really about time and temperature, and it's about assumptions about you know the dose needed and then the starting concentration that you might have in the meat to begin with and all of that.
Right. Well, I mean, that that's kind of though, I think where a lot of our people kind of want to go mentally, right? Is to that level. And so then we're talking about, okay, I mean, bot the botulism is the one everyone worries about, right? But I mean, listeria, I'm worried about a lot.
Um, especially if you're gonna chill it afterwards and store it, right? Um I just had a a real good friend of the family almost die from uh listeria. Uh so it's uh w what do we do about peep when we're cooking in the zone where because it happens all the time, let's say on fish, right? Especially fish. Like red meats, I can cook a red meat.
Most red meats I can cook above 54, 55 Celsius uh Celsius. In that range, I am killing stuff. I'm actively killing. Now, am I gonna cook it long enough to get enough you know reductions of of uh levels that that we could talk about, but I'm actively killing stuff, right? When I'm doing fish, right, I'm lower, often lower.
I'm often in the low 50s, like 50, 52, 53. It's not, and you're not cooking it for a long time. So you're clearly not killing all of the pathogens of interest. And uh some pathogens of interest, right, don't even really necessarily on paper anyway, uh, start dying until you hit 55, right? I mean, I mean, uh, I just think people like see all these numbers and they get weirded out.
So what about these zones where I'm cooking uh a salmon? Let's let's be specific. I'm cooking a salmon, I'm gonna cook it to 52 uh Celsius, right? Let's say uh let's say the salmon is in a tube shaped, and for the center to come up to that, it takes an hour or 45 minutes. I now chill it and eat it.
What am I doing to myself? What is actually happening, right? Because once it gets up into 50, you know, 52, is am I in stasis? Am I growing? Is it the same as if it I had just eaten it raw out of the fridge?
Worse, better? Where are we? Yeah, so you you there's a lot to unpack here. And and also uh there's actually I need to kind of get the numbers up in front of me and work through, work through some stuff because I don't want to mislead people. But I do want to come back to something that you said.
You mentioned listeria. And I would put, although Listeria is an infectious organism, uh, it is not, I don't put it in the same bucket as salmonella and pathogenic E. coli. We know from dose response studies with Listeria, although it is an infectious organism, it tends to be a high dose organism. And so, as I mentioned before, the probability of illness from a single salmonella cell is on the order of one in a hundred or one in two hundred or one in three hundred.
The probability of illness from a single Listeria cell, even for somebody who's immunocompromised, is much more in the ballpark of one in a million or even lower risk. And so generally speaking, the foods where Listeria pose a risk are foods where, because of that extended refrigerated storage you mentioned, the any surviving organisms have managed to grow to high levels such that there's a reasonable probability of illness. So they grow best at about 37 degrees C, which is about 98 uh.6 uh degrees F. And as you move above that, they grow more slowly, but then at some point it switches over from slower and slower growth to starting to get some thermal inactivation. And yeah, and then fish for like you said, fish is for sure a challenge because it's it's really easy to uh to overcook it.
120, and I haven't really sat here and done the math carefully, 125 degrees Fahrenheit or 52 degrees C, that seems like an awfully low temperature. And again, I know we had some correspondence before the before the the this call about that. I need to get those numbers up in front of me and sort of figure out what we know about where where does salmonella because it's one thing to say, okay, salmonella is not growing. Um and certainly if you're if you're quote unquote cooking it in the temperature where you're actually growing salmonella, that's not a best practice, but figuring out where that dividing line is between where growth stops and inactivation begins. That's that's that's that's the sweet spot, right?
And and that's where we want to be, we want to be above that that temperature. Right. Well, in the early 2000s, a lot of chefs were you know fabricating their fish under kind of sushi grade uh conditions, right? So the concept was you can eat this raw. They would vacuum pack it and then they would store it as though they were storing stuff that would be served raw, sushi style, right?
Then they would put it and they would uh cook it to the in Celsius. You ready for this? They would cook it in the forties, right? Like like 50 was high. They would cook it in the 40s, but they would only do it for like 20 minutes, basically warming it.
And you would get this kind of jewel-toned, uh kind of fudgy, and nine out of ten, well, well, about half the people hate it and about half the people love it, which is why you don't see it that often in restaurants anymore, just because so many people are actually turned off by it, right? Uh but the people who loved it loved it, and it definitely looks amazing. Um sometimes it can get really fishy, which is the problem with it. But my argument for why that was okay was because it just wasn't, it wasn't being cooked long enough to have anything bad happen, right? So Bruno Gusot, the you know, grandpa of of uh Juscatans, he calls it, you know, precise temperature cooking, uh, you know, he was like, but it can grow, it it can cause histamines.
I was like, okay, okay, Bruno, whatever, man. But you know what I'm saying is like I didn't feel like people were making it too unsafe. It's when you it's when you're gonna cook something for an extended period of time and then chill it and then serve it later that I start getting worried, no. Well, yeah, so certainly if you are well, I'll have to use air quotes here. If you're cooking something at 40 degrees C, which is 104 degrees Fahrenheit, you're not really cooking it.
You really are incubating it. And that is definitely within the temperature range where where salmonella can grow. Now, if you're quote unquote cooking it for an hour or two, you're not gonna get much salmonella growth in that hour or two. If you're gonna cook it, if you're gonna incubate it till I cook it for 10 or 12 hours or overnight, well, now you're you're you're really just making an incubator there. And then and then if you refrigerate it properly, well, then now you're not getting any salmonella growth.
But if you had some listeria, you're not gonna kill the listeria at 40 degrees C. And then if you do extended refrigerated storage, no, well now Listeria is going to start to multiply. Um, and then you could be amplifying the risk there. Yeah, no, no one I think was no one ever argued that like th those ones when they came back, you couldn't doggy bag that stuff. It had to be eaten or pitched.
You know what I mean? Like no one was I mean, like anyone who doggy bag that let people take it home that that you know, that's like poison in a cup right there. That's no good. Uh but why don't dogs get sick from this stuff? Why can't a dog arrive?
Well, the the organisms that they're slight. Some here's the thing some organisms make dogs sick, don't make us sick. Some that make us sick don't make dogs sick, and some some don't make either of us sick, and some will make both of us sick. So you really can't be, you really you really can't. It's not it's not uh definitive.
All right. But so let's let's say I'm cooking in the 50s now. Like I'm not I'm I'm up at like 50, 52, right? What I'm interested in is the shape of the bacterial growth curve, right? Where it starts up in this exponential thing where it gets real fast, as you say, up towards, you know, it's it's real low at the fridge level, and then it ramps way the heck up towards body temperature.
It peaks out somewhere, right? And then after that peak, it kind of crashes precipitously, right? So it's like there are these zones that aren't in the kill zone, but they're pretty much in the same zone as refrigeration in terms of growth, right? Right, and you're absolutely right. That that they they drop off precipitously, and that's also part of the reason why our knowledge in this area is a bit fuzzy.
It's it's challenging to do those experiments, right? It's relatively easy to study from room temperature down to refrigeration because the the change in the growth kinetics of the organism is more gradual. Above the optimum, um, up to the maximum, like you said, it's a precipitous drop. So again, I'm just looking at the limit uh to growth when other conditions are near the optimum for salmonella, and the maximum temperature recorded here is 46.2. So that's a so you're talking about 50.
So so if you're if you're quote unquote cooking at 50, which is 122 Fahrenheit, you're outside the range for Salmonella growth. So Salmonella concentration is not going up. Um you're outside the range for Listeria, so Listeria concentration is not going up. The extent to which it's going down, that we have to I'd have to go look at some some different numbers. Now I will point out, we talked about Bacillus series before.
Bacillus series, apparently, um, according to the source I'm looking at right now, can grow up to 55. Now, again, do we have Bacillus serious in fish? Well, not uh not a lot, but you know what? You might have uh it's a see, Bacillus is a spore former. And so those spores can be anywhere.
And so could you have bacillus spores on fish? Yeah, absolutely. You could. Could you could you be encouraging their growth at 50 degrees? Yeah, you might be.
Uh it's probably not growing super fast, but but it could. But again, again, it's all it's about time and temperature. Right, because I just don't think the majority of us are cooking long enough to pasteurize, and I'm also not that worried about it when I cook for my family. I mean, maybe in a restaurant situation, I would have to probably pasteurize it because that's the way the rules are written, but anyway. Let me get to some Patreon questions because I will get I will get my head torn off uh otherwise.
Uh John Denton wrote in, I recently bought a freeze dryer, and I'm curious whether or not the freeze-drying process kills harmful microorganisms or just renders them dormant. I'd guess that removing 100% of their water content would kill at least some, but perhaps not all. Thanks for the show. Yeah, great, great question. And I we could answer freeze drying and freezing at the same at the same time.
Both freezing and freeze drying will kill some of the bacteria, but it's not a reliable way to kill to kill bacteria. And so, yeah, and then you take the water out and you might stress the cells a little bit more. But actually, when we want to store bacterial cultures for long periods of time, we actually freeze dry them. And so it's an excellent way to preserve bacteria for a long time. So so, yes, you might get some kill, you might get, you know, 90% kill, but you still got you still potentially have have more there.
And you might not even get 90% kill. So for sure, it's not a definitive kill step. Let me ask you this question. Not a kill step, but let's say I eat it in the freeze-dried state and I don't rehydrate it. What's the risk?
In other words, will they rehydrate and become undormant inside my gut? Entirely possible, yes. Because you know that they're basically uh and and yeah, so they're they're basically going to be rehe rehydrating as they move through your body. And so they're not you're not pooping out freeze-dried particles, right? So they're they're getting hydrated at some point.
And yes there is a potential risk there. Speak for yourself. All right. Uh Dustin I'm just kidding. Dustin Melldrum wrote in uh what does your home dishwashing and or kitchen cleaning routine look like?
I'm less concerned about things going into and coming out of the dishwasher unless I should be but I suspect I'm overwashing some items while creating potential risks elsewhere. If I'm being honest, I'm really after bare minimum standard operating procedure, but we've all witnessed friends and family clean in ways that have made us feel sad, mad, or glad. What is the best practice? Well you know it depends upon the context. We did an episode of Risky or Not recently where we talked about our rather uh haphazard procedures that we have for cleaning our various coffee making apparatuses right and so I use an aerobress uh which gets a rinse off in cold water and that's it it doesn't get put in the dishwasher it doesn't get washed with soap because you know coffee coffee residue black coffee residue it's not gonna it's not gonna do much there.
On the other hand the cup in which I make uh my coffee uh you know gets put in the dishwasher at least if it's not the fancy electronic one that keeps my coffee warm that would probably fry it if I put that in the dishwasher so um so it you know it it depends certainly when I think about risk in the kitchen I think about you know if if I'm if I if if I have uh uh raw meat and I'm cutting raw meat on a cutting board that cutting board is going in the dishwasher probably on the sanitized cycle um you know the that's it it's probably a good idea to to run all of your dishes through the dishwasher on a regular basis just just in case but again really think about where the risk is coming from and then and then practice that practice that risk management accordingly and again part of this is risk management but part of it is grossness I mean who who wants to eat on a plate that didn't get cleaned or like we're we're still optimizing our new dishwasher and occasionally uh we find uh food residue on some of the silverware well that's that's that's gross right I'm not gonna eat I'm not gonna eat off that use that silverware that has dry food that's that's stuck on I'm gonna put that back in the sink and wash it by hand and then maybe wash it in the dishwasher again. So some of it is aesthetics right and and uh and some of it is safety but again when it comes to safety really think about like where's the contamination coming from right um and then of course you know if you if you do a good job of cleaning it you're gonna you know clean the food debris away then that's going to make it a lot easier um for you know to to not have uh to not have bacteria there because it's visibly clean again not that not that you can't have bacteria there but but you know getting things visibly clean goes a long way towards making things uh more safe so in a restaurant we use sani what percentage of people use a sandy solution when they're wiping stuff down at home or is like the home like spray bottle cleaner like effective enough what about like salting your boards if they're wood all this kind of stuff yeah well the general expert recommendation is uh wooden cutting boards should not be used for meat. Now there was there was some controversy some some years ago my my friend and and now dearly departed uh Dean Cliver uh did some research showing that actually there might be natural oils in the wood that actually kill pathogens, but other people publish data saying, well, no, they just they just harbor the bacteria, they go into the wood. So we'll we'll set that aside. But again, the general uh expert recommendation from people like me is don't use wooden cutting boards for for raw meat, use plastic cutting boards for that.
Um and then yeah, I think the the sanitary practices vary from from home to home. Um I know in my house, uh my wife has a uh a mild sanitizer, and then we have the Clorox sanitizer that we break out when we know that we've been working with raw meat and there's a potential for for issues there. And so uh and then when we talk, you know, one of the things that people love to talk about too when we talk about kitchen hygiene and safety is like what's the what's the dirtiest spot in the house? And uh research has shown, not research I've done, but research done by my colleagues have shown that uh the sink drain is very dirty. Why uh very has high levels of bacteria.
Why? Well, it's always wet because it's where the water goes when it leaves the leaves the sink, and it tends to have food particles, and if you add food and water together, that's a recipe for growing bacteria. And then the other the other risky site in the kitchen is the sponge for much the same reason, right? The sponge holds water and also uh can hold food particles, and that's a recipe for growing uh growing microorganisms, which is which is not a good thing. Sponge in the in the dishwasher on sanitize takes it back to zero or fills machine pitch.
Uh I would say certainly putting it in the dishwasher on the sanitized cycle is a great practice. That's something that we do. If you don't have an automatic dishwasher, you can microwave your sponges. Be sure to add some water uh when you microwave them and don't over-microwave them because if you microwave a dry sponge, you will start a fire in your microwave. Oh, I like this.
Which is not a good thing. I'm totally doing this. I'm totally doing this. And then I what I will also say. Can you microwave Scotch price?
Please, please uh do so at your own risk. Yeah. Um and then what I'll what I will also say with uh with respect to um uh sponges and dishwashers is is if you run through the sanitized cycle and it still smells funky, that's probably a good time to get a new sponge, right? Because uh there may be stuff that that sanitizcle doesn't take care of. Sponge is a weird word, Stas.
What do you think of the word sponge? Fine. Fine. Sponge. Sponge.
Uh all right. Um, by the way, what do you what do you recommend for a mild sandy? Because a lot of people don't like the smell of bleach getting wiped all over their stuff. Do you have uh something that you uh recommend? Oh I I don't know.
My my confidentially she'll never hear this. My wife makes something that is very mild and doesn't really work in my opinion. So I don't I don't have a strong opinion. I'll make sure to send this somehow. Uh uh Yeah.
The I have to be honest, I'm gonna cut, I'm gonna cut on wood because I hate cutting on plastic. God do I hate cutting on plastic. Yeah, yeah. Yeah. So let me ask you a question.
So when you if you're cutting raw meat on wood, um, what is your practice for how you're gonna render that uh clean and sanitized? Uh I usually scrub it with soap and the hottest water with uh with like a a scotch bright pad, and then I I I don't know why, but this is what I leave it wet and I sprinkle coarse salt all over it. I rub the salt in, I walk away for an hour, and then I come and I rinse it off again. That's what I do. But but I should probably create well, wow, but that's gonna mess up the wood, right?
I you know, I love I love the fact that you have this defined process. I I wonder if anybody's actually studied that process in the literature. Because I've got to imagine cleaning and scale. So like a lot, you know, a big part of what soap does is remove bacteria, it doesn't necessarily kill bacteria, and then the physical action of scrubbing is also going to help. The salt probably has some benefits.
So I'm very cute. Obviously, it's not going to be the same as as sanitizing, but I really wonder what the what the practice might be. And then the other thing that I've heard people recommend too with the wooden cutting board is um, yeah, you can you can um uh wash it with soap and water um and then pour like boil some water in a kettle and then pour boiling water over it. That's gonna have some benefit as well. But I don't know, again, I don't know what that'll do to the wood.
I mean, the salt thing I learned from a butcher because they can't move their giant butcher blocks, right? So they would just scrape scrape salt into it with those, you know, those brushes that look like like a like a billion knives, you know what I'm talking about? Those brushes that look like a billion knives. It was like they would scrape the salt in with that, and that's why all it wasn't necessarily from the hacking, it was from the is from the the salting that the butcher blocks would get that super uh con. Well, I guess it depends on how you think about it, the divot in the middle, yeah.
Uh Slim Joe writes in question for the show Can someone be immune or develop resistance to the common food board uh foodborne pathogens slash toxins? Because I've eaten a lot of questionable food over the years and have never gotten sick. So cast iron stomach from Slim Joe wants to know if it's because he takes risks all the time that he's a little more bulletproof. That's a that's a good question. I would love to get him in for a challenge study where we feed him some things that they're really on purpose.
I don't do that kind of research in my lab, but it would be very interesting to study him. But um, so you know, people often ask this question when they talk about like safety of drinking the water in you know developed countries with a developing economy. It's like, well, well, why don't we just do what they do? And it's like, well, yeah, but you know what they have is they have uh infant death from uh from from diarrhea, right? And so yeah, we could raise a population that was more resistant to these things if we expose people.
Uh and so um I would say that that you know there is there in I'm I don't want to, you know, I mean sli Slim Joe's experience is his experience, but um there's not clear evidence, and this uh this would only work for some organisms, it wouldn't work for others' organisms. We know with norovirus, for example, the or the virus uh mutates over time, and just because you've been sick with that with norovirus in the past doesn't mean that a new norovirus might not make you sick. And so I certainly wouldn't recommend what what Slim Joe is advocating for the general public because here's the thing you know, it it it might make you immune, but it might also kill you. And so uh, you know, we've been we've made a decision. Like we do this with a lot of a lot of diseases, I guess, including uh SARS-CoV-2 now, is we have vaccines for people, um, or we just try to keep the those those uh organisms out of the food supply.
So, what about the flip side of the Slim Joe question? Do you think we're all gonna get sicker now that we're coming out of the pandemic and we've been kind of uh in a bubble for a long time? It's really interesting. You know, there is some evidence that recently came out, I think it was uh something uh from from CDC that show that reported foodborne disease outbreaks are down. Now, notice I said reported.
Now that might be because the reporting has been compromised because people have been drawn, people that are involved in public health have been drawn away from food to work on the pandemic. And so that may that may play a role in that lack of reporting. You know, people have hypothesized, well, because we're all cleaning and sanitizing everything, and we're you know, we're not we're not eating in restaurants, we're eating at home, you know. It's like, well, but you know, when you make yourself sick with food poisoning at home, you don't necessarily report that to the health department. So I'm not sure that we're that the pandemic has really made a difference either way I don't think it's created a situation where because of lack of exposure to food worn pathogens we're more likely to get sick.
I just I don't think that's that I don't think it's a reasonable hypothesis. I would have guessed that the average restaurant is safer than the average home you think I'm wrong. Well the problem is it's hard to know but yeah I mean certainly restaurants are following the food code they have people that have been trained. But again if a restaurant screws up they make a lot of people sick same with a with a big food processor right if a big food processor screws up they're gonna make a lot of people sick if you screw up in your home uh you don't make that many people sick but but that so I I I guess I would say I think what you propose is reasonable but I don't know of any evidence that that where anybody has really studied and nor how would you study uh home foods I guess no people like my my podcast partner Ben do big bring people into his catch his test kitchen and ask them to prepare foods as they would in the home and so I guess to that extent we can figure out what they do and and for sure they they screw things up um we'll get Slim Joe in we'll get Slim Joe in and test it out. Jordan wrote in uh food safety question do you have any advice for chefs that produce fermented foods in their restaurants and struggle with providing uh proving to health inspectors that it's safe in particular Koji based ferments that may take months to finish at ambient temperature and that may not have a final pH below 4.6 and as a as a coded to that I will say and I'm sure you are aware of this that uh people are doing um dry aging of uh meats at temperatures like this with Koji on the outside now.
So it's not just uh vegetables. Uh comments. Yeah, it's it's tricky, and there's not a lot of research base out there. I mean, we do know uh that with respect to dry aging of meats, uh it really depends upon the temperature and it depends upon the environmental humidity, right? And so, you know, the the relative humidity in the environment, that can that can play a role.
Um, yeah, and with fermentations, it's all about the starting materials. It's it may be about the the um the salt, the starting salt concentration. Um yeah, it I would say to answer that question definitively, we have to dig into the literature and find out like are there, you know, who studied this and what do the pathogens do when they when they follow uh procedures like the ones being suggested here. Yeah, I think Jeremy's actually doing the challenge studies now, right? He is, and in the back of their book too, there's some uh sample HACC plans that are meant to just kind of be like general guidance as to how to do that.
Yeah, but yeah, but nothing has meaning until the challenge studies have been done, right? I mean, for those for those of you that we're talking about, yeah, like it's like we can all have our theories about this and we can control our environment, but until we've proven that a particular set of controls is in fact safe, we haven't proved it. Yeah. I know Jeremy says like when he pickles, you know, salt pickles things, he really only uses like the master sauerkraut thing. And then when the health inspector comes in, he tries to, you know, show them that it's really just doing the same thing, just with a different vegetable, but the same salt content and that kind of stuff.
Yeah, but on the other hand, isn't it possible that it takes X amount more time for the salt to penetrate into Y vegetable than it does to penetrate into cabbage, which is basically just a tube? Anyway. Uh Devin Patel writes in I I'm for it. I'm just saying, like I I'll eat the stuff. I'm just saying from an actual proof standpoint, it's a little more dicey.
Wouldn't you say, Doc? Yeah, you're and I think you put your finger on it, right? Like the salt penetration, just like when you're making acidified food, the acid penetration, if you have a big piece of vegetable versus a a small, uh small thin sliver, that penetration is going to be different. So yeah, and like you said, the challenge studies are the way to go because that's going to show in the most definitive way possible, assuming you've done the study correctly, uh, that this is in fact an acceptable practice. Does it make you as mad as it makes me when you see a recipe for a brine and they just and they just talk about the brine versus the liquid and they don't take into in consideration the entire weight of the of the product that they're working with?
Does it make you as mad as it makes me? Probably not as mad, but I get your point. I hate it. I hate it. It's it's salt for the entire freaking thing, people.
It's how much salt do you have in the entire thing? Yeah. Okay. As I like to say, the denominator matters, you know, in whatever you're talking about. If you don't tell me the denominator, I don't care what the numerator is, right?
Tell me the total denominator. It's because people the reason I think it got that way is because people aren't thinking about equilibriums, right? So they're they're in general basing their salt content on like short-term brining, like if you're doing a turkey or something, and they're not thinking about equilibrium brine concentration. Whatever, I can't get into it. I don't have time because I gotta get to these questions.
Devin Patel writes in Does high pressure sterilization affect the flavor of drinks? Is it a good solution for RTD beverages? Do you have any uh knowledge on that? Yeah, so we've done some research on high pressure processing. Um, and it it it is it's good for killing vegetative organisms.
It's not it's not very good for killing spore-forming organisms. And so for that reason, um, it you can't really use it to control Clostridium botulinum. And so for acidified drinks for things that have a low pH, it works pretty well. It tends to be less, it has tends to have less effect on the flavor uh than it than thermal processing than using heat. And so, yeah, it's uh it's an expensive process.
The equipment is very expensive, and uh it's kind of dangerous too. You don't want to be next to one of these things when the seals fail, uh, you know, because it can kill you. Um so yeah, but it's it's an interesting technology, it's an expensive technology, uh, but it has some clear benefits overheat. Will it kill yeasts and other things like that? Because that's what most of our spoilage is in a higher acid thing.
It's not yeah, yeah. Yeah, yeah, yeah. Yeast are relatively easy to kill, like bacteria, they don't they don't form spores. Um, so yeah, it should be should be good for controlling yeast. Uh Jennifer Mallon wrote in, I have a question about defrosting food.
They always say to defrost meat in the refrigerator, but whenever I do that, it does not defrost all the way. I eat half the meat is still frozen after 24 hours. How do I safely defrost meat while actually defrosting it? Yeah, that's a great question. This is one that we've also talked about on risky or not and and my other podcast, uh, food safety talk.
And so the key is you can't, although the expert, the quote unquote experts uh will tell you you cannot safely defrost at room temperature. I submit that you can. The trick is to keep the temperature of the food low because that's where the bacteria are, that's where they're going to grow, and then you want to let it have the outside the surface temperature stay cool while the inside thaws. And what one way you can do that is by putting the food in a paper bag. A paper bag traps the cold air from the thawing food and helps to keep the surface temperature low.
Now you can't let it go on and thaw so long that the surface temperature starts to rise because that's when you can start to get uh bacterial growth. But yeah, and and I would submit to you that you can thaw food in the refrigerator eventually, you just have to wait long enough. Because if you wait long enough, again, to equilibrium, the temperature will equilibrate and it should, and it should the inside will thaw eventually. But if your fridge is set really cold, um it's going to take longer. But yes, you can thaw safely at room temperature, just keep the surface temperature low by perhaps placing the food in the something like a paper bag.
I mean, the problem is thawed food is a much better insulator than frozen food. I mean, it's it's a huge pain in the butt. Uh, what about the what about Zimblock and running water? That also works for sure. You can you can you can do that as well.
If it's again, if it's raw meats, just be careful because the if you if the bag leaks, you're going to spread the meat juices all over your sink or wherever you happen to be doing the thaw. Uh Ahuva got Dina Road in. How do I explain clearly and simply to my busy overwhelmed followers, many of whom often host multi-course meals, that chicken soup you've left cooling on the stove overnight is not safe to serve, that no amount of boiling will change that. And this goes back to a huge argument that was, I know had with uh Ruleman and Harold McGee and a bunch of other people a couple years ago. But your comments, please.
Yeah, so again, think back to the earlier part of the conversation and Bacillus serious, right? Bacillus spores will survive the cooking process of the soup. Um, if the spores are there, they can germinate and grow. They will make a heat stable toxin. And so no amount of boiling will get rid of that.
Staphylococcus aureus also makes a heat-stable toxin, so it can be there. Um, and so for sure, it's not a best practice. It's not safe. You may get you may skate by if you're lucky enough to avoid uh contamination with bacillus, but someday your luck will run out and you will give somebody food poisoning. Now, if you if I pressure cook something and then I don't take the lid off the pressure cooker and let it cool, that's okay, right?
Because the inside's not getting recontaminated. Um if you pressure cooked it, like what you're talking about, like home canning, kind of pressure cooking? No, like let's say you're making, let's say you're doing a stew and you pressure cook it and then you turn it off and then you go to bed, you know, put it away, but you haven't opened it yet. It's fine, isn't it? Well, but well, but there might still be spores in that in the ingredients, right?
Uh, which will have survived the cooking process. So that will that will eliminate the Staphococcus aureus risk, but it won't eliminate the Bacillus serious risk or the Clostridian perfringance risk. Even at pressure cooking temperatures. I I think so. Again, the devils and the details with respect to the temperatures involved, but these spores are incredibly heat resistant.
Nastasia hates spores. And that's all the time. Jared Johnson said, uh, can you please talk about well you you already talked about perpetual stew? Um is the real danger in the practice of refreezing food that has been defrosted, is that you can forget how many times you have done this, it wouldn't know how long the food has been cumulative cumulatively defrosted. And I know you probably you saw this on Twitter, but do you have any comments?
Yeah, I so it was too complicated. I didn't have time on Twitter, but basically the idea is the big thing I worry about with repeated freeze thaw cycles, and you know this as a chef, is the quality is gonna go to hell, right? Like so the quality won't be good. Now, theoretically, if you're taking the organism up into the danger zone and then back down, you might be getting some bacterial growth over time. But again, depending upon the temperatures and the times and the cycles, I'm really just mostly worried about quality because you know, if you freeze thaw food multiple times, it just destroys the texture.
And so it's just not gonna, it's just not gonna be good for that reason, not because of safety. Yeah. Yeah. Yeah. And is Capri San wants to know are you really worried about aflatoxins or not?
Like do you wake up and like afotoxin? No, I try to avoid eating moldy food. I I do as a kid, I ate a lot of peanut butter, and I do continue to eat peanut butter to this day. And so I do worry about maybe low levels of apletoxin over time. But you know, uh I I tend again if I was eating a lot of moldy foods, I would worry about it, but I I don't eat, I don't eat you know, moldy bread, and so I think that's pretty pretty good risk management there.
Pitch any moldy bread. Yeah, for sure I would. Don't throw away the moldy slice, pitch the whole thing. Well, again, it's it's all the in the details, right? Like it depends on how moldy it is.
Uh I've actually got a uh an assignment to do for a consulting assignment to do to do a deep dive on moldy bread to come up with some definitive recommendations. So it really depends upon the amount of mold. It's just one small spot of mold on one slice, you can get rid of that. But you know, I find also that moldy bread can be surprising. Like I pulled away a moldy slice and then later on discovered that actually the mold had penetrated further than I thought.
And so, you know, molds are sneaky, so be be uh be alert. Uh yeah, be careful with moldy bread. Yeah. And last, uh Steve Lister wants to know do water bottles really expire and he uh has been using his container of miso paste forever. Is it fine as long as it's not furry?
Even miso, maybe if it is. Yeah, I would I would say miso paste again, I don't have the definitive uh pH and water activity in front of me, but if as long as there's no visible mold and it tastes okay, it's probably okay to use. Um, and then with respect to the dates on water bottles, yeah, that date is probably for not probably that date is for freshness and for quality, it's not for um microbiology. And so the the the water was good at day zero when it was sealed into the bottle. It's gonna be good um forever, basically, because there aren't any pathogens there.
If if there were, they they wouldn't they wouldn't grow in in water. All right. Well, uh, you know, we could go on this uh like this uh forever, but uh we would get in trouble if we did that. So uh Dr. Don, thanks for uh thanks for coming on.
And uh hopefully, you know, people who listen to this, they should oh John, what do you want to say about the Patreon? They should follow you, bug counter on uh the Twitter. And I'm I see you as answer people's questions there all the time. We get somehow sucked into the same Twitter storm sometimes. So uh Yeah, but for all our listeners, uh you guys should sign up for our Patreon if you haven't done so yet.
Uh it gives you access to the call and number, free or you know, this uh whole chat room feature that Jackie Molecules has set up on Discord, uh advanced notice about upcoming guests where you can ask questions. Your questions will always get answered on air. Um, just a whole lot of perks. So check out patreon.com slash cooking issues and sign up. Who do we have next week?
Eric Wareheim. Eric Wareheim with his new book Foodheim. Foodheim. Uh and uh thanks, Professor. On the way out, I would just like to, on a sad note, uh we mourn the passing this week of Ann Saxelby uh from Saxobe Cheesemongers.
Uh so our hearts go out to her whole family, uh Patrick Martins and uh Heritage Food people. Uh cooking issues.
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