August 13, 2025 • 30 mins
Eggcellent question! Jorge goes beyond the shell to find out why there's no consensus on whether to keep eggs cool or not.
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Speaker 1 (00:00):
Hey, welcome to sign Stuff, a production of iHeartRadio, I'm
Hoar hit Cham and today we're cracking open a question
that humans have been asking for over a century. Do
eggs need to be refrigerated? We're gonna unscramble this mystery
by taking a deep dive into the signs of eggs,
(00:21):
answering questions like what does it mean for an egg
to be Grade A or B? How does salmonella get
inside an egg? And is it okay to eat raw eggs?
As we'll learn, the answer kind of depends on where
you live, So get ready to whisk up some knowledge
and become an expert as we tackle the question do
(00:45):
eggs need to be refrigerated?
Speaker 2 (00:49):
Enjoy? Hey? Everyone?
Speaker 1 (00:56):
Okay, if you're someone who eats eggs every day or
only occasionally, you're not alone. According to the US Department
of Agriculture, the average American eats about two hundred and
ninety eggs a year. The average European eats two hundred
and seventeen eggs per year, although it varies by country.
(01:16):
For example, in Greece, the average person eats one hundred
and forty one eggs a year, but in Denmark they
eat three hundred in Asia. The average person in Hong
Kong is estimated to eat four hundred and fifty eggs
per year. Scientists estimate that by twenty thirty, about ninety
three million tons of eggs, that's about two trillion eggs
(01:40):
will be produced and sold.
Speaker 2 (01:42):
Worldwide per year.
Speaker 1 (01:44):
Purely, eggs are a big part of our diet, and
for good reason. Eggs are full of nutrients and they're
relatively cheap. According to historians, humans have been farming eggs
for thousands of years. The first chicken is said to
have been domesticated around ten thousand years ago, and throughout
all that time we didn't refrigerate the eggs. Refrigerators were
(02:08):
invented in the eighteen hundreds, with the first home fridge
being sold in the early nineteen hundreds. And yet, at
least in the US, eggs are found in the refrigerated
section of the supermarket, and the fridge is where most
of us keep.
Speaker 2 (02:22):
Them when we bring them home.
Speaker 1 (02:25):
But if you talk to anyone with backguard chickens, or
if you travel abroad a lot, you might have noticed
some people just leave their eggs out, which also makes sense.
Keeping eggs cool makes moving and storing eggs more complicated
and expensive and they take up space in your fridge.
So do we have to refrigerate eggs? To help answer
(02:48):
this question, it reached out to a bonafide expert, Professor
Kapil Cho Saltcar. Here's what he does. Well, thank you
doctor Cho sal Car for today no problems a pleasure.
Can you please tell us who you are and what
you do.
Speaker 3 (03:03):
I teach at the University of athlet in Australia and
I also practice of thetan Areas a Poultrybaateinaria. Microsearch group
has been researching on eggs and Salmanala for the last
several years.
Speaker 1 (03:14):
So he tell us what are the current laws or
guidelines or customs about storing eggs in different regions of
the world.
Speaker 3 (03:21):
Interestingly, the rules and the regulations around egg storage or
refrigerations they do vary from country to country. The US,
for example, stipulates the eggs they must be stored or
held in transported at the temperature no greater than seven
point two degrees that is not more than forty five
degrees fahrenheit. In the UK, eggs must be held at
(03:42):
the constant temperature that can range between five to twenty
degrees celsius. There's a difference there. If you look at
the European Union, for example, they dictate that eggs must
not be refrigerated. So there's a variation from country to country.
In Australia, very interesting. Every state has got a different
(04:03):
recommendation around the transport. Many grocery shops they're still store
eggs at room temperature.
Speaker 1 (04:10):
Do you know how what it is in other parts
of the world like Asia, or.
Speaker 3 (04:15):
When I visit a number of farms in India, for example,
those eggs are not stored at a refrigeration temperature on
the farm or during transport. In a big supermarkets in
India they are stored sometimes in the refrigerator, but not
always so.
Speaker 1 (04:34):
Laws and regulations around refrigerating eggs are different depending on
the country. For example, in Latin America, there are also
no regulations about egg storage. In Brazil, which produces about
ninety three billion eggs a year, it's only suggested that
you put your eggs in the fridge after you buy them. Now,
(04:56):
when I heard this, I thought it was odd that
different parts of the world have different requirements by refrigerating eggs.
Speaker 2 (05:05):
Why is that?
Speaker 1 (05:06):
Is it optional? Does it depend on the egg or
the culture of each region. Well, it turns out a
big reason is a word that should be familiar to
anyone who does any regular cooking with chicken products, and
the word is salmonilla. But the main concern seems to
(05:28):
be about bacteria.
Speaker 2 (05:29):
Is that right?
Speaker 3 (05:30):
For eggs? Yes, so a name of vectory is called salmonella.
Some of you may have heard about it in the audience,
but that's a predominant concern across the world in terms
of food safety.
Speaker 1 (05:40):
Can you tell us what salmonilla is?
Speaker 3 (05:42):
It's a bacteria. People may have heard its name in
two contexts. So when it's salmonala typhee, which is called
a typhotole salmonella, it results because of the the hicle
or contamination typically what we call human to human transmission
when it comes to eggs and chicken may to some degree.
We are talking about the salmonella which falls into a
(06:04):
category of non typhoid or salmonella, so it does not
cause typhoid, it causes food poisoning. So there are two
main ones. But there are many, many types of salmonella,
more than two thousand, five hundred different types what in
the world, So there are many of them.
Speaker 1 (06:21):
Wow, there, but not all.
Speaker 3 (06:22):
Of them are as nasty as some of them, like
Typhanirum and introduce, and there are some others as well.
Speaker 1 (06:28):
These are all bacterias. They're all called salmonilla, but they're
just different kinds of species of bacteria.
Speaker 3 (06:34):
There are different kinds of species of bacteria within salmonilla.
Speaker 2 (06:38):
Okay.
Speaker 1 (06:38):
The first thing to know about salmonilla is that there
are many different kinds of salmonilla. As like your chul
Salker says, there are over twenty five hundred different serophars
or strains of salmonilla. Some cause typhoid fever and are
transmitted from humans to humans by poop, and some cause
(07:00):
food poisoning and are transmitted from animals to humans by
eating contaminated foods. So a salmonilla, these are bacteria that
are already in the chicken, so they just live in
the gastrointestinal tract they do.
Speaker 3 (07:16):
Birds themselves do not show any clinical signs or symptoms.
They don't get sick because of salmonilla. So as a veterinarian,
there is no way to find out whether chickens are
carrying salmonilla or not until we really test those samples,
and it's expensive testing is not cheap. It's expensive to.
Speaker 1 (07:36):
Test the chicken to see if they have salmonilla.
Speaker 3 (07:38):
If they have.
Speaker 1 (07:39):
Salmonilla, Okay, here's the thing about salmonilla. It's kind of
impossible to tell if a chicken has it or not.
The bacteria can live happily inside the chicken's guts and
you might never know. First of all, it doesn't affect
the chickens. They don't get sick from it. And second,
it doesn't really come out of their food unless the
(08:01):
chicken is stressed.
Speaker 3 (08:06):
So they have to test their poop. And birds often
don't shed that in their faces. It can become a
normal part of their gastro in personal microflora and can
live happily in the gut of the birds. So if
you keep your birds happy and comfortable, they tend not
to shed it. When birds are stressed, they tend to
(08:28):
shed it. Then the bacteria tends to replicate in the
higher number and contaminate the eggshell. Okay, So to recap
many chickens may have some type of salmonella. Not all
salmonillas can cause foodborne illness, and not all chickens may
(08:48):
carry salmonilla. Some of them do, some of them don't
so unless we do testing of their feces at the
right time.
Speaker 1 (08:56):
But it's out there. Some chickens have it.
Speaker 3 (08:58):
Sometimes out some chickens have an unfortunately only way to
find that out is when people get sick. Chickaus don't get.
Speaker 1 (09:07):
Sick, all right, So some chickens have salmonilla, and sometimes
that salmonilla can be the kind that gives you food poisoning.
Now the question is how does that bacteria get on
the eggs. We're going to get into the nitty gritty
of chicken anatomy and egg production after the break. Stay
(09:28):
with us. You're listening to sign stuff and we're back.
Speaker 2 (09:40):
Okay.
Speaker 1 (09:40):
We're answering the question of whether eggs need to be refrigerated,
and the answer seems to involve a bacteria called salmonilla.
We learned some kinds of salmonilla can live inside the
cuts of chickens, and some of those can give you
food poisoning through the eggs. Now, the question is how
does the bacteria get on the eggs. Here's what our expert,
(10:02):
doctor Joe scar said. Now, how did they sell many
like kid on the eggs?
Speaker 3 (10:08):
Not a lot of people who are not farm in
background understands where egg comes from. It comes from a
backside of a chicken. And the literally one hole there
where the poop and the egg comes out from.
Speaker 1 (10:21):
It's the same hole.
Speaker 3 (10:22):
Egg comes from, the same hole where the poop comes from. Okay,
he just.
Speaker 1 (10:28):
Give me the anatomy of a chicken. Like the egg
forms in the same tract as the poop.
Speaker 3 (10:33):
So there is one part of chicken's body it's called
as a reproductive tract. We call that oviduct. That's where
the formation of egg takes place. There is a different
part where which is a gastro intestinal tract. That's where
the poop is formed. There is another part where it
connected to kidneys. That's where the urine comes from. But
(10:55):
all of those openings they open in the part called
kloa and so that's the common opening. That's where the
egg and fieces or urine also comes from. So going
back to salmonella, what happens is it can come through
feces of the birds on the eggshell.
Speaker 1 (11:16):
Hey guess what chicken butt is where both chicken poop
and eggs come out of the chicken. This opening called
the cloaca is how salmonilla can get on the egg,
specifically the egg shell. But here's a shaker. There are
also ways for salmonilla to get inside the egg.
Speaker 3 (11:41):
Some types of salmonella can contaminate egg from outside, and
you can have some types of salmonella that can contaminate
egg content from inside. The good example is Salmonella introdude
to this that has a potential to multiply in the orbituct,
(12:02):
which is an egg forming organ or the reproductive organ.
So what happens is once the bacteria is lodged in
the reproductive organ, it can contaminate the inside of an
egg when egg is developing. One of the things that
I would like to tell your audience that salmanala just
love the egg yolk. It's the iron contained in the yolk.
(12:27):
Bacteria loves iron. As soon as the bacteria goes near yolk,
it replicates very fast and it becomes more virulent.
Speaker 1 (12:37):
WHOA Okay, how often does the bacteria get in the yolk?
Is that common or rare?
Speaker 3 (12:45):
It's not very common, at least in Australia. It is
not very common unless you really stuff up egg in
the kitchen and store it. Barrio mishandling eggs. Most of
the commercial eggs produced in the countries like the UK, Australia,
also in the US. They are produced in a very
(13:05):
highly regulated environment. They are vaccinated against salmonella, so the
chances are low that you will get a type of
some bacteria in yolk during the formation of egg.
Speaker 1 (13:16):
I see, But if they are Baccia.
Speaker 3 (13:18):
Chickens, it's very difficult to see how those eggs are collected,
how they are kept, and how they're refrigerated, and how
people handle them, so it's difficult to tell that I see.
Speaker 1 (13:30):
So salmonella can get inside the egg directly during the
formation of the egg. Egg scientists called this vertical transmission
of salmonilla, but it's very rare, at least for commercial
eggs like the kind you get in stores. More concerning
is what scientists called horizontal transmission of salmonilla.
Speaker 3 (13:51):
That means the bacteria is in the book or is
on the shelf because of the contamination buffaces or the
dust that can be in the shed and through the shell,
the bacteria can migrate inside an egg.
Speaker 1 (14:07):
Okay, you're probably thinking, but forehead, the whole point of
having a hard egg shell is to protect the egg.
How does some manilla that might be in the chicken
poop or dirt get inside the egg.
Speaker 3 (14:20):
Well.
Speaker 1 (14:20):
One easy way is for there to be cracked in
the egg shell. The egg gets bumped or dropped, there
could be cracks for bacteria to come into the egg.
So if you see a cracked egg, you may want
to not eat that one or all. The other way
bacteria can go in is by getting sucked in. How
(14:42):
does it get through the egg shell?
Speaker 3 (14:44):
If you look at the body temperature of birds are
hotter than humans. Their body temperature is around thirty nine
degrees to forty one degrees, so around three to four
degrees higher than us.
Speaker 1 (14:56):
Wow.
Speaker 3 (14:57):
Because they are fully feathered, birds don't have sweat lands,
so they can't release sweat. So one of their thermoregulatory
mechanism that is patting, and so in the shed there
has to be an air movement. So these birds, they
are kept in a farm environment where temperature is set
at twenty one to twenty three degrees, So hot birds
(15:20):
in a cool farm. And that's why those temperatures in
the shed are set at that temperature to keep chickens
happy and cool. So imagine a chicken is laying an
egg and the temperature of egg is around thirty nine
to forty one degrees, and then egg is laid in
a room where temperature is set at twenty one to
(15:41):
twenty three degrees. Okay, so this is going to cause
a temperature great and difference.
Speaker 1 (15:47):
Right.
Speaker 3 (15:48):
So now egg is cooling down from third thirty nine
to twenty three degrees and during that cooling down period,
there can be a negative pressure that can be developed
inside and egg which can suck bacteria from the shell.
Wa and so those bacterias get sucked into the pores.
Speaker 1 (16:07):
Oh okay, let me see. The egg comes out hot,
but it comes out into cool a shed and as
it cools, I guess the inside shrinks because it's cooling,
that's right.
Speaker 2 (16:19):
That's right.
Speaker 1 (16:19):
That tends to suck things from the outside of the egg.
Speaker 3 (16:22):
That's right. So to give you quite an example, if
you have a kind of a warm or hot water
in the water plastic water bottle, it kill cools down,
it shrinks, the bottle shrinks, right, right. The same thing
would happen with an egg. But because egg shell is porous,
then that bacteria can get sucked in inside the shell pores.
So that's the starting point. That's how bacteria gets in.
Speaker 1 (16:45):
Yeah, eggs can suck bacteria in if they come out
warm out of the chicken into a cool chicken coop
or cage. The shrinking egg white and yolk can pull
bacteria in. And this is something I did in know
before egg shells have pores. I see, I guess I
(17:06):
didn't know that egg shells had pores, Like, why doesn't
the stuff come out then? If it has holes in it?
Speaker 3 (17:12):
Hual is very porous. And going back to the structure
of an egg, the moder nature has designed that egg
for development of chicken embryo. So when embryo develops, it
also needs to undergo a process we called as embryo metabolism.
So it breathes and it also excretes the waste material
and so for excretion of that waste material, it has
(17:32):
to come out through pores. And that's why it has
actual pores.
Speaker 1 (17:36):
What even as the embryo grows inside, it's breathing through
the egg shell and it's excreting through the axel too.
Speaker 3 (17:44):
So embryo takes twenty one days to hatch. And as
embryo grows, it produces lot of heat. So those shell
pores actually help to remove that heat from the egg,
so you can say embryo is breathing, although technically it's
not breathing through just through egg shell, but it helps
to remove all the heat and the metabolized water through
(18:05):
shell shell portes.
Speaker 1 (18:06):
Oh fascinating is that how eggs also get fertilized through
the pores?
Speaker 3 (18:11):
No, so it's the egg gets fertilized in the part
of oviduct or birds called as infundibulum. So that's a
funnel shaped structure which is right next to the ovary
of birds.
Speaker 1 (18:24):
I guess I had another birds in the bees of chickens.
Speaker 3 (18:27):
Yeah, yeah, that would be another session to talk about
how our domating and our fertilusion takes place. Quite a
lot of interesting science behind that as well.
Speaker 1 (18:38):
Yeah, let's not get into how baby chickens are made.
But the point is that egg shells have tiny little
holes or pores because eggs are made to grow embryos inside,
and as embryos grow, they need those pores to pass
oxygen in CO two and water vapor to support their metabolism.
(19:00):
According to reports, a typical egg has thousands of pores
on their egg shell and up to twenty liters of
gases can pass through these pores throughout the life of
the egg up until the baby chick is born. Okay,
So to quickly recap salmonilla, the kind that can give
you food poisoning, can go from the chicken poop to
(19:22):
the outside of eggs because they both come out the
same hole. And from there the salmonilla can go inside
the egg through cracks or the egg shell pores, or
it can contaminate other foods. If you handle eggs and
then say stick your finger in a potato salad, that
can add salmonilla to your potato salad. Well, now the
(19:44):
obvious question here is why don't we just wash the
egg just get rid of the salmonilla on the egg shell.
Speaker 2 (19:52):
It's not that easy. When we come.
Speaker 1 (19:54):
Back, we'll find out why washing your eggs is not
such an egg sele the idea stick around.
Speaker 2 (20:03):
We'll be right back. Welcome back.
Speaker 1 (20:13):
Okay, we floored that big motivation for refrigerating eggs is salmonilla,
which mostly ends up on the outside of the egg
on the shell. So now the question here is I
guess a naive question would be why don't we just
wash the eggs when they come out of the chicken?
Speaker 3 (20:30):
Egg Washing is a whole lot lot of science. So
again if you look at different laws of regulation in
different countries and the US, egg washing is mandatory for
all eggs that are commercially produced and sold. In Europe,
egg washing is not allowed. And in Australia are the
large proportion of eggs sold commercially are washed. Not all
(20:51):
of them are washed, large proportion of them are washed.
Speaker 1 (20:53):
When you say washed, what does that mean like rinse
with water or actual soilp and chemicals or disinfectant.
Speaker 2 (20:59):
Yeah, so that are.
Speaker 3 (20:59):
Different and different different ways people do it. Some people
they wash and sanitize, other people just wash. So it
depends on what procedures or the farms are following. So
egg washing machine, egg goes into a washer so where
the brushes are set to remove the visible fickle material
from the eggshell. Then they are sanitized with flordinated water
(21:21):
or food grade sanitizer and then they're dried. So that's step.
But again there's a whole lot of signs behind how
that washing is done. But I do not recommend people
who have got back at chickens to wash egg at
home because you need right temperature of the water while
washing an egg. If eggs are being laid and you're
collecting fresh eggs, which are warm, and if you're putting
(21:42):
that in a very cold water under the tap, you're
likely crack the egg because the difference in temperature radio
On the other hand, if you're collecting egg it has
cooled down because you just don't know what time of
the day you're collecting eggs, water temperature outside in the
chicken cook you just don't know what temperature that egg is.
If you are washing it with other very hot or
(22:02):
very cold water, you're likely to crack those eggs. So
don't wash eggs at home. You might splash contaminated water
everywhere as well, so definitely wash your hands after handling egg.
Don't wash egg but when you are handling eggs, wash
your hands because there's likely to be a bacteria on
the shell.
Speaker 1 (22:20):
I think I read some ra that washing can also
damage either the lining or the inside of the egg.
Is that true. Yes.
Speaker 3 (22:26):
When you talked about protective mechanism, it's called as cuticle,
also referred as bloom on the eggs shell. That's another
barrier or defense mechanism of an eggshell which prohibits or
which stops bacteria from migration into shell. But one of
the limitations of the cuticle is that it is not
uniformly distributed around the shell. And when we looked at
(22:50):
the cutical deposition on the egg coming from a particular flock,
there can be a lot of variation and how cuticle
is deposited, but it definitely has a capacity to protect
this egg from bacteri little penetration and during washing, the
washing can actually damage that cuticle during the washing process.
Speaker 1 (23:10):
Which makes the egg more vulnerable to bacteria getting in
that can.
Speaker 3 (23:14):
But after washing and after drying, those eggs are oiled
to see the pores so the bacteria doesn't get in
when the posts are sealed, and that is done to
replace the job of cuticle because critical is damaged during washing.
Speaker 1 (23:29):
Oh, fascinating. So when you say they're washed commercially, they're
usually washed and sealed, washed and oiled and oil the
porste Yeah, so that's fascinating. So if I go to
Europe and I'm in Europe, then I'm not allowed to
wash eggs. But if I cross over to the US.
Speaker 3 (23:44):
In the US, yes, in Australia, majority of them are washed.
Speaker 1 (23:49):
All right, you can wash eggs, but it's best to
leave it to the professionals. Okay, I decided to ask
that thertial saltcar directly whether eggs should be refrigerated. Here's
what he said. Okay, so something that I can get
into the egg vertically horizontally, is that then the reason
(24:09):
to refrigerate eggs?
Speaker 3 (24:11):
Yeah. Look, the migration of bacteria across the shell or
through horizontal way of transmission is also driven by temperature.
When eggs are stored at a room temperature, when they
are not a refrigerator or not cooled, then the rate
of penetration could be higher across the eggshell.
Speaker 1 (24:32):
Why is that?
Speaker 3 (24:33):
Because that temperature is helpful for bacteria to survive and
also penetrate across the shell. That a number of different
organs or bacteria that get switched on at that temperature.
That a lot of the bacterial genome. People have looked
at how the gene expressions of the bacteria look like
at that temperature when they migrate or when they penetrate
(24:55):
across the shell.
Speaker 1 (24:56):
WHOA, So, then refrigeration, how does that help prevents the
bacteria from going inside?
Speaker 3 (25:02):
Look, it slows down the activity of bacteria overall. As
soon as you lower the temperature. It does not kill
the bacteria, so it just slows down the growth and
it can slow down the multiplication of the bacteria as well.
If the egg internal contents are contaminated, that's the important
thing to remember. And also remember that if eggs are
(25:22):
stored inside the cool temperature refrigerator temperature, that lowers the
risk of the footbone illness overall.
Speaker 1 (25:30):
So then do eggs need to be refrigerated.
Speaker 3 (25:33):
I would recommend yes, refrigeration of egg that if you
have eggs at home, I'll definitely recommend to keep them
in the fridge. Don't leave them on the bench because
if you leave eggs on the bench, the egg white,
which is inside an egg, it tends to deteriorate. That
means it tends to go more runny. So you might
(25:54):
remember the old method of testing if eggs are fresh
or stale, because the fresh eggs would sink, can stale
eggs would float. That is because of the egg white
and the apace, So airspace is more in older eggs
and stale eggs. So I would recommend to refrigerateates.
Speaker 1 (26:11):
Interesting what your Chou Socar is saying here is that
refrigerating eggs also helps keep eggs fresh studies have found
that the quality of the egg goes down over time.
Egg whites get runnier and less acidic, and they also
lose weight over time. If you crack an egg on
a plate and measure the height of the blob of
(26:33):
egg white, that height, also called the hot unit, is
a measure of the quality or grade.
Speaker 2 (26:39):
Of an egg.
Speaker 1 (26:41):
Great AA is the tallest, followed by A, B, and C.
That height also decreases with time. But if you refrigerate
the egg, all these processes slow down, so the eggs
need to be refrigerated.
Speaker 2 (26:58):
The answer is.
Speaker 1 (27:00):
Really an egg can last just fine if you leave
it on the counter for days, but putting it under
fridge does lower the risk of salmonilla getting in the egg,
and it keeps the egg fresher. This explains why different
countries and regions have such different rules and regulations. And
(27:21):
what does that depend on what a country decides to do.
Speaker 3 (27:24):
I think it depends on the risk and the prevalence
means to the extent to which the bacteria are present
in the population on the flock. Also depends on the
type of bacteria that is in the country. For example,
for many many years, salmonella in treated was not endemic
in Australia. It is considered exotic and notifiable. What it
(27:48):
means is it is not as common to see salmonella
in treatedis in Australia compared to the UK or the US,
and that's why most of the laws were developed, which
has pit pour purpose for that respect to country and
the industry. But it is quite prevalent in Europe, in
the UK and the US as well.
Speaker 1 (28:09):
I see, so then it makes more sense for them
to be more careful.
Speaker 3 (28:13):
Yeah, in general, industry has always been quite careful because
it affects the business. Food safety is an important element
for egg business. Egg farmers, they do lots of good
things to produce a very safe product for humans, and
so it all boils down to how that egg is
handled in the kitchen environment. So we just had to
(28:34):
be very careful on how we prepare dishes metal from eggs.
People don't always wash their hands in the kitchen after
handling eggs. After breaking an egg in a pan, they
quickly wipe their hands against the apron if they're wearing apron,
or they just wipe their hand with the kitchen towel.
They could break egg with the knife, which is also
(28:54):
used for cutting vegetables. People can do weird and wonderful
things in the kitchen and wroment and they well, they cook.
Speaker 1 (29:00):
What happens?
Speaker 3 (29:01):
Since you are essentially cross contaminating things in the kitchen.
Speaker 1 (29:04):
The saveest thing is to assume that the outside of
the egg probably has some manilla on it, and that
the inside could also have some manilla inside of it.
Speaker 3 (29:13):
Yeah, so there is a possibility of bacteria being there
on the shell. There is a low possibility of bacteria
being in satin egg. It's not zero, it's low. So
just wash your hands after you are handling eggs and
cook eggs properly.
Speaker 1 (29:30):
All right, thanks for joining us. We hope you had
a shell over time. And if you don't like egg puns,
I'm sorry for all the bad yolks. See you next time.
You've been listening to Science Stuff production of iHeartRadio Bring
the produced by Me or Hm hedited by Rose Seguda,
(29:53):
executive producer Jerry Rowland, audio engineer and mixer Casey Pegrom
and you can follow me on social media.
Speaker 2 (29:59):
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Speaker 1 (30:00):
PhD Comics and the name of your favorite platform. Be
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Hey, welcome to sign Stuff, a production of iHeartRadio, I'm
Hoar hit Cham and today we're cracking open a question
that humans have been asking for over a century. Do
eggs need to be refrigerated? We're gonna unscramble this mystery
by taking a deep dive into the signs of eggs,
(00:21):
answering questions like what does it mean for an egg
to be Grade A or B? How does salmonella get
inside an egg? And is it okay to eat raw eggs?
As we'll learn, the answer kind of depends on where
you live, So get ready to whisk up some knowledge
and become an expert as we tackle the question do
(00:45):
eggs need to be refrigerated?
Speaker 2 (00:49):
Enjoy? Hey? Everyone?
Speaker 1 (00:56):
Okay, if you're someone who eats eggs every day or
only occasionally, you're not alone. According to the US Department
of Agriculture, the average American eats about two hundred and
ninety eggs a year. The average European eats two hundred
and seventeen eggs per year, although it varies by country.
(01:16):
For example, in Greece, the average person eats one hundred
and forty one eggs a year, but in Denmark they
eat three hundred in Asia. The average person in Hong
Kong is estimated to eat four hundred and fifty eggs
per year. Scientists estimate that by twenty thirty, about ninety
three million tons of eggs, that's about two trillion eggs
(01:40):
will be produced and sold.
Speaker 2 (01:42):
Worldwide per year.
Speaker 1 (01:44):
Purely, eggs are a big part of our diet, and
for good reason. Eggs are full of nutrients and they're
relatively cheap. According to historians, humans have been farming eggs
for thousands of years. The first chicken is said to
have been domesticated around ten thousand years ago, and throughout
all that time we didn't refrigerate the eggs. Refrigerators were
(02:08):
invented in the eighteen hundreds, with the first home fridge
being sold in the early nineteen hundreds. And yet, at
least in the US, eggs are found in the refrigerated
section of the supermarket, and the fridge is where most
of us keep.
Speaker 2 (02:22):
Them when we bring them home.
Speaker 1 (02:25):
But if you talk to anyone with backguard chickens, or
if you travel abroad a lot, you might have noticed
some people just leave their eggs out, which also makes sense.
Keeping eggs cool makes moving and storing eggs more complicated
and expensive and they take up space in your fridge.
So do we have to refrigerate eggs? To help answer
(02:48):
this question, it reached out to a bonafide expert, Professor
Kapil Cho Saltcar. Here's what he does. Well, thank you
doctor Cho sal Car for today no problems a pleasure.
Can you please tell us who you are and what
you do.
Speaker 3 (03:03):
I teach at the University of athlet in Australia and
I also practice of thetan Areas a Poultrybaateinaria. Microsearch group
has been researching on eggs and Salmanala for the last
several years.
Speaker 1 (03:14):
So he tell us what are the current laws or
guidelines or customs about storing eggs in different regions of
the world.
Speaker 3 (03:21):
Interestingly, the rules and the regulations around egg storage or
refrigerations they do vary from country to country. The US,
for example, stipulates the eggs they must be stored or
held in transported at the temperature no greater than seven
point two degrees that is not more than forty five
degrees fahrenheit. In the UK, eggs must be held at
(03:42):
the constant temperature that can range between five to twenty
degrees celsius. There's a difference there. If you look at
the European Union, for example, they dictate that eggs must
not be refrigerated. So there's a variation from country to country.
In Australia, very interesting. Every state has got a different
(04:03):
recommendation around the transport. Many grocery shops they're still store
eggs at room temperature.
Speaker 1 (04:10):
Do you know how what it is in other parts
of the world like Asia, or.
Speaker 3 (04:15):
When I visit a number of farms in India, for example,
those eggs are not stored at a refrigeration temperature on
the farm or during transport. In a big supermarkets in
India they are stored sometimes in the refrigerator, but not
always so.
Speaker 1 (04:34):
Laws and regulations around refrigerating eggs are different depending on
the country. For example, in Latin America, there are also
no regulations about egg storage. In Brazil, which produces about
ninety three billion eggs a year, it's only suggested that
you put your eggs in the fridge after you buy them. Now,
(04:56):
when I heard this, I thought it was odd that
different parts of the world have different requirements by refrigerating eggs.
Speaker 2 (05:05):
Why is that?
Speaker 1 (05:06):
Is it optional? Does it depend on the egg or
the culture of each region. Well, it turns out a
big reason is a word that should be familiar to
anyone who does any regular cooking with chicken products, and
the word is salmonilla. But the main concern seems to
(05:28):
be about bacteria.
Speaker 2 (05:29):
Is that right?
Speaker 3 (05:30):
For eggs? Yes, so a name of vectory is called salmonella.
Some of you may have heard about it in the audience,
but that's a predominant concern across the world in terms
of food safety.
Speaker 1 (05:40):
Can you tell us what salmonilla is?
Speaker 3 (05:42):
It's a bacteria. People may have heard its name in
two contexts. So when it's salmonala typhee, which is called
a typhotole salmonella, it results because of the the hicle
or contamination typically what we call human to human transmission
when it comes to eggs and chicken may to some degree.
We are talking about the salmonella which falls into a
(06:04):
category of non typhoid or salmonella, so it does not
cause typhoid, it causes food poisoning. So there are two
main ones. But there are many, many types of salmonella,
more than two thousand, five hundred different types what in
the world, So there are many of them.
Speaker 1 (06:21):
Wow, there, but not all.
Speaker 3 (06:22):
Of them are as nasty as some of them, like
Typhanirum and introduce, and there are some others as well.
Speaker 1 (06:28):
These are all bacterias. They're all called salmonilla, but they're
just different kinds of species of bacteria.
Speaker 3 (06:34):
There are different kinds of species of bacteria within salmonilla.
Speaker 2 (06:38):
Okay.
Speaker 1 (06:38):
The first thing to know about salmonilla is that there
are many different kinds of salmonilla. As like your chul
Salker says, there are over twenty five hundred different serophars
or strains of salmonilla. Some cause typhoid fever and are
transmitted from humans to humans by poop, and some cause
(07:00):
food poisoning and are transmitted from animals to humans by
eating contaminated foods. So a salmonilla, these are bacteria that
are already in the chicken, so they just live in
the gastrointestinal tract they do.
Speaker 3 (07:16):
Birds themselves do not show any clinical signs or symptoms.
They don't get sick because of salmonilla. So as a veterinarian,
there is no way to find out whether chickens are
carrying salmonilla or not until we really test those samples,
and it's expensive testing is not cheap. It's expensive to.
Speaker 1 (07:36):
Test the chicken to see if they have salmonilla.
Speaker 3 (07:38):
If they have.
Speaker 1 (07:39):
Salmonilla, Okay, here's the thing about salmonilla. It's kind of
impossible to tell if a chicken has it or not.
The bacteria can live happily inside the chicken's guts and
you might never know. First of all, it doesn't affect
the chickens. They don't get sick from it. And second,
it doesn't really come out of their food unless the
(08:01):
chicken is stressed.
Speaker 3 (08:06):
So they have to test their poop. And birds often
don't shed that in their faces. It can become a
normal part of their gastro in personal microflora and can
live happily in the gut of the birds. So if
you keep your birds happy and comfortable, they tend not
to shed it. When birds are stressed, they tend to
(08:28):
shed it. Then the bacteria tends to replicate in the
higher number and contaminate the eggshell. Okay, So to recap
many chickens may have some type of salmonella. Not all
salmonillas can cause foodborne illness, and not all chickens may
(08:48):
carry salmonilla. Some of them do, some of them don't
so unless we do testing of their feces at the
right time.
Speaker 1 (08:56):
But it's out there. Some chickens have it.
Speaker 3 (08:58):
Sometimes out some chickens have an unfortunately only way to
find that out is when people get sick. Chickaus don't get.
Speaker 1 (09:07):
Sick, all right, So some chickens have salmonilla, and sometimes
that salmonilla can be the kind that gives you food poisoning.
Now the question is how does that bacteria get on
the eggs. We're going to get into the nitty gritty
of chicken anatomy and egg production after the break. Stay
(09:28):
with us. You're listening to sign stuff and we're back.
Speaker 2 (09:40):
Okay.
Speaker 1 (09:40):
We're answering the question of whether eggs need to be refrigerated,
and the answer seems to involve a bacteria called salmonilla.
We learned some kinds of salmonilla can live inside the
cuts of chickens, and some of those can give you
food poisoning through the eggs. Now, the question is how
does the bacteria get on the eggs. Here's what our expert,
(10:02):
doctor Joe scar said. Now, how did they sell many
like kid on the eggs?
Speaker 3 (10:08):
Not a lot of people who are not farm in
background understands where egg comes from. It comes from a
backside of a chicken. And the literally one hole there
where the poop and the egg comes out from.
Speaker 1 (10:21):
It's the same hole.
Speaker 3 (10:22):
Egg comes from, the same hole where the poop comes from. Okay,
he just.
Speaker 1 (10:28):
Give me the anatomy of a chicken. Like the egg
forms in the same tract as the poop.
Speaker 3 (10:33):
So there is one part of chicken's body it's called
as a reproductive tract. We call that oviduct. That's where
the formation of egg takes place. There is a different
part where which is a gastro intestinal tract. That's where
the poop is formed. There is another part where it
connected to kidneys. That's where the urine comes from. But
(10:55):
all of those openings they open in the part called
kloa and so that's the common opening. That's where the
egg and fieces or urine also comes from. So going
back to salmonella, what happens is it can come through
feces of the birds on the eggshell.
Speaker 1 (11:16):
Hey guess what chicken butt is where both chicken poop
and eggs come out of the chicken. This opening called
the cloaca is how salmonilla can get on the egg,
specifically the egg shell. But here's a shaker. There are
also ways for salmonilla to get inside the egg.
Speaker 3 (11:41):
Some types of salmonella can contaminate egg from outside, and
you can have some types of salmonella that can contaminate
egg content from inside. The good example is Salmonella introdude
to this that has a potential to multiply in the orbituct,
(12:02):
which is an egg forming organ or the reproductive organ.
So what happens is once the bacteria is lodged in
the reproductive organ, it can contaminate the inside of an
egg when egg is developing. One of the things that
I would like to tell your audience that salmanala just
love the egg yolk. It's the iron contained in the yolk.
(12:27):
Bacteria loves iron. As soon as the bacteria goes near yolk,
it replicates very fast and it becomes more virulent.
Speaker 1 (12:37):
WHOA Okay, how often does the bacteria get in the yolk?
Is that common or rare?
Speaker 3 (12:45):
It's not very common, at least in Australia. It is
not very common unless you really stuff up egg in
the kitchen and store it. Barrio mishandling eggs. Most of
the commercial eggs produced in the countries like the UK, Australia,
also in the US. They are produced in a very
(13:05):
highly regulated environment. They are vaccinated against salmonella, so the
chances are low that you will get a type of
some bacteria in yolk during the formation of egg.
Speaker 1 (13:16):
I see, But if they are Baccia.
Speaker 3 (13:18):
Chickens, it's very difficult to see how those eggs are collected,
how they are kept, and how they're refrigerated, and how
people handle them, so it's difficult to tell that I see.
Speaker 1 (13:30):
So salmonella can get inside the egg directly during the
formation of the egg. Egg scientists called this vertical transmission
of salmonilla, but it's very rare, at least for commercial
eggs like the kind you get in stores. More concerning
is what scientists called horizontal transmission of salmonilla.
Speaker 3 (13:51):
That means the bacteria is in the book or is
on the shelf because of the contamination buffaces or the
dust that can be in the shed and through the shell,
the bacteria can migrate inside an egg.
Speaker 1 (14:07):
Okay, you're probably thinking, but forehead, the whole point of
having a hard egg shell is to protect the egg.
How does some manilla that might be in the chicken
poop or dirt get inside the egg.
Speaker 3 (14:20):
Well.
Speaker 1 (14:20):
One easy way is for there to be cracked in
the egg shell. The egg gets bumped or dropped, there
could be cracks for bacteria to come into the egg.
So if you see a cracked egg, you may want
to not eat that one or all. The other way
bacteria can go in is by getting sucked in. How
(14:42):
does it get through the egg shell?
Speaker 3 (14:44):
If you look at the body temperature of birds are
hotter than humans. Their body temperature is around thirty nine
degrees to forty one degrees, so around three to four
degrees higher than us.
Speaker 1 (14:56):
Wow.
Speaker 3 (14:57):
Because they are fully feathered, birds don't have sweat lands,
so they can't release sweat. So one of their thermoregulatory
mechanism that is patting, and so in the shed there
has to be an air movement. So these birds, they
are kept in a farm environment where temperature is set
at twenty one to twenty three degrees, So hot birds
(15:20):
in a cool farm. And that's why those temperatures in
the shed are set at that temperature to keep chickens
happy and cool. So imagine a chicken is laying an
egg and the temperature of egg is around thirty nine
to forty one degrees, and then egg is laid in
a room where temperature is set at twenty one to
(15:41):
twenty three degrees. Okay, so this is going to cause
a temperature great and difference.
Speaker 1 (15:47):
Right.
Speaker 3 (15:48):
So now egg is cooling down from third thirty nine
to twenty three degrees and during that cooling down period,
there can be a negative pressure that can be developed
inside and egg which can suck bacteria from the shell.
Wa and so those bacterias get sucked into the pores.
Speaker 1 (16:07):
Oh okay, let me see. The egg comes out hot,
but it comes out into cool a shed and as
it cools, I guess the inside shrinks because it's cooling,
that's right.
Speaker 2 (16:19):
That's right.
Speaker 1 (16:19):
That tends to suck things from the outside of the egg.
Speaker 3 (16:22):
That's right. So to give you quite an example, if
you have a kind of a warm or hot water
in the water plastic water bottle, it kill cools down,
it shrinks, the bottle shrinks, right, right. The same thing
would happen with an egg. But because egg shell is porous,
then that bacteria can get sucked in inside the shell pores.
So that's the starting point. That's how bacteria gets in.
Speaker 1 (16:45):
Yeah, eggs can suck bacteria in if they come out
warm out of the chicken into a cool chicken coop
or cage. The shrinking egg white and yolk can pull
bacteria in. And this is something I did in know
before egg shells have pores. I see, I guess I
(17:06):
didn't know that egg shells had pores, Like, why doesn't
the stuff come out then? If it has holes in it?
Speaker 3 (17:12):
Hual is very porous. And going back to the structure
of an egg, the moder nature has designed that egg
for development of chicken embryo. So when embryo develops, it
also needs to undergo a process we called as embryo metabolism.
So it breathes and it also excretes the waste material
and so for excretion of that waste material, it has
(17:32):
to come out through pores. And that's why it has
actual pores.
Speaker 1 (17:36):
What even as the embryo grows inside, it's breathing through
the egg shell and it's excreting through the axel too.
Speaker 3 (17:44):
So embryo takes twenty one days to hatch. And as
embryo grows, it produces lot of heat. So those shell
pores actually help to remove that heat from the egg,
so you can say embryo is breathing, although technically it's
not breathing through just through egg shell, but it helps
to remove all the heat and the metabolized water through
(18:05):
shell shell portes.
Speaker 1 (18:06):
Oh fascinating is that how eggs also get fertilized through
the pores?
Speaker 3 (18:11):
No, so it's the egg gets fertilized in the part
of oviduct or birds called as infundibulum. So that's a
funnel shaped structure which is right next to the ovary
of birds.
Speaker 1 (18:24):
I guess I had another birds in the bees of chickens.
Speaker 3 (18:27):
Yeah, yeah, that would be another session to talk about
how our domating and our fertilusion takes place. Quite a
lot of interesting science behind that as well.
Speaker 1 (18:38):
Yeah, let's not get into how baby chickens are made.
But the point is that egg shells have tiny little
holes or pores because eggs are made to grow embryos inside,
and as embryos grow, they need those pores to pass
oxygen in CO two and water vapor to support their metabolism.
(19:00):
According to reports, a typical egg has thousands of pores
on their egg shell and up to twenty liters of
gases can pass through these pores throughout the life of
the egg up until the baby chick is born. Okay,
So to quickly recap salmonilla, the kind that can give
you food poisoning, can go from the chicken poop to
(19:22):
the outside of eggs because they both come out the
same hole. And from there the salmonilla can go inside
the egg through cracks or the egg shell pores, or
it can contaminate other foods. If you handle eggs and
then say stick your finger in a potato salad, that
can add salmonilla to your potato salad. Well, now the
(19:44):
obvious question here is why don't we just wash the
egg just get rid of the salmonilla on the egg shell.
Speaker 2 (19:52):
It's not that easy. When we come.
Speaker 1 (19:54):
Back, we'll find out why washing your eggs is not
such an egg sele the idea stick around.
Speaker 2 (20:03):
We'll be right back. Welcome back.
Speaker 1 (20:13):
Okay, we floored that big motivation for refrigerating eggs is salmonilla,
which mostly ends up on the outside of the egg
on the shell. So now the question here is I
guess a naive question would be why don't we just
wash the eggs when they come out of the chicken?
Speaker 3 (20:30):
Egg Washing is a whole lot lot of science. So
again if you look at different laws of regulation in
different countries and the US, egg washing is mandatory for
all eggs that are commercially produced and sold. In Europe,
egg washing is not allowed. And in Australia are the
large proportion of eggs sold commercially are washed. Not all
(20:51):
of them are washed, large proportion of them are washed.
Speaker 1 (20:53):
When you say washed, what does that mean like rinse
with water or actual soilp and chemicals or disinfectant.
Speaker 2 (20:59):
Yeah, so that are.
Speaker 3 (20:59):
Different and different different ways people do it. Some people
they wash and sanitize, other people just wash. So it
depends on what procedures or the farms are following. So
egg washing machine, egg goes into a washer so where
the brushes are set to remove the visible fickle material
from the eggshell. Then they are sanitized with flordinated water
(21:21):
or food grade sanitizer and then they're dried. So that's step.
But again there's a whole lot of signs behind how
that washing is done. But I do not recommend people
who have got back at chickens to wash egg at
home because you need right temperature of the water while
washing an egg. If eggs are being laid and you're
collecting fresh eggs, which are warm, and if you're putting
(21:42):
that in a very cold water under the tap, you're
likely crack the egg because the difference in temperature radio
On the other hand, if you're collecting egg it has
cooled down because you just don't know what time of
the day you're collecting eggs, water temperature outside in the
chicken cook you just don't know what temperature that egg is.
If you are washing it with other very hot or
(22:02):
very cold water, you're likely to crack those eggs. So
don't wash eggs at home. You might splash contaminated water
everywhere as well, so definitely wash your hands after handling egg.
Don't wash egg but when you are handling eggs, wash
your hands because there's likely to be a bacteria on
the shell.
Speaker 1 (22:20):
I think I read some ra that washing can also
damage either the lining or the inside of the egg.
Is that true. Yes.
Speaker 3 (22:26):
When you talked about protective mechanism, it's called as cuticle,
also referred as bloom on the eggs shell. That's another
barrier or defense mechanism of an eggshell which prohibits or
which stops bacteria from migration into shell. But one of
the limitations of the cuticle is that it is not
uniformly distributed around the shell. And when we looked at
(22:50):
the cutical deposition on the egg coming from a particular flock,
there can be a lot of variation and how cuticle
is deposited, but it definitely has a capacity to protect
this egg from bacteri little penetration and during washing, the
washing can actually damage that cuticle during the washing process.
Speaker 1 (23:10):
Which makes the egg more vulnerable to bacteria getting in
that can.
Speaker 3 (23:14):
But after washing and after drying, those eggs are oiled
to see the pores so the bacteria doesn't get in
when the posts are sealed, and that is done to
replace the job of cuticle because critical is damaged during washing.
Speaker 1 (23:29):
Oh, fascinating. So when you say they're washed commercially, they're
usually washed and sealed, washed and oiled and oil the
porste Yeah, so that's fascinating. So if I go to
Europe and I'm in Europe, then I'm not allowed to
wash eggs. But if I cross over to the US.
Speaker 3 (23:44):
In the US, yes, in Australia, majority of them are washed.
Speaker 1 (23:49):
All right, you can wash eggs, but it's best to
leave it to the professionals. Okay, I decided to ask
that thertial saltcar directly whether eggs should be refrigerated. Here's
what he said. Okay, so something that I can get
into the egg vertically horizontally, is that then the reason
(24:09):
to refrigerate eggs?
Speaker 3 (24:11):
Yeah. Look, the migration of bacteria across the shell or
through horizontal way of transmission is also driven by temperature.
When eggs are stored at a room temperature, when they
are not a refrigerator or not cooled, then the rate
of penetration could be higher across the eggshell.
Speaker 1 (24:32):
Why is that?
Speaker 3 (24:33):
Because that temperature is helpful for bacteria to survive and
also penetrate across the shell. That a number of different
organs or bacteria that get switched on at that temperature.
That a lot of the bacterial genome. People have looked
at how the gene expressions of the bacteria look like
at that temperature when they migrate or when they penetrate
(24:55):
across the shell.
Speaker 1 (24:56):
WHOA, So, then refrigeration, how does that help prevents the
bacteria from going inside?
Speaker 3 (25:02):
Look, it slows down the activity of bacteria overall. As
soon as you lower the temperature. It does not kill
the bacteria, so it just slows down the growth and
it can slow down the multiplication of the bacteria as well.
If the egg internal contents are contaminated, that's the important
thing to remember. And also remember that if eggs are
(25:22):
stored inside the cool temperature refrigerator temperature, that lowers the
risk of the footbone illness overall.
Speaker 1 (25:30):
So then do eggs need to be refrigerated.
Speaker 3 (25:33):
I would recommend yes, refrigeration of egg that if you
have eggs at home, I'll definitely recommend to keep them
in the fridge. Don't leave them on the bench because
if you leave eggs on the bench, the egg white,
which is inside an egg, it tends to deteriorate. That
means it tends to go more runny. So you might
(25:54):
remember the old method of testing if eggs are fresh
or stale, because the fresh eggs would sink, can stale
eggs would float. That is because of the egg white
and the apace, So airspace is more in older eggs
and stale eggs. So I would recommend to refrigerateates.
Speaker 1 (26:11):
Interesting what your Chou Socar is saying here is that
refrigerating eggs also helps keep eggs fresh studies have found
that the quality of the egg goes down over time.
Egg whites get runnier and less acidic, and they also
lose weight over time. If you crack an egg on
a plate and measure the height of the blob of
(26:33):
egg white, that height, also called the hot unit, is
a measure of the quality or grade.
Speaker 2 (26:39):
Of an egg.
Speaker 1 (26:41):
Great AA is the tallest, followed by A, B, and C.
That height also decreases with time. But if you refrigerate
the egg, all these processes slow down, so the eggs
need to be refrigerated.
Speaker 2 (26:58):
The answer is.
Speaker 1 (27:00):
Really an egg can last just fine if you leave
it on the counter for days, but putting it under
fridge does lower the risk of salmonilla getting in the egg,
and it keeps the egg fresher. This explains why different
countries and regions have such different rules and regulations. And
(27:21):
what does that depend on what a country decides to do.
Speaker 3 (27:24):
I think it depends on the risk and the prevalence
means to the extent to which the bacteria are present
in the population on the flock. Also depends on the
type of bacteria that is in the country. For example,
for many many years, salmonella in treated was not endemic
in Australia. It is considered exotic and notifiable. What it
(27:48):
means is it is not as common to see salmonella
in treatedis in Australia compared to the UK or the US,
and that's why most of the laws were developed, which
has pit pour purpose for that respect to country and
the industry. But it is quite prevalent in Europe, in
the UK and the US as well.
Speaker 1 (28:09):
I see, so then it makes more sense for them
to be more careful.
Speaker 3 (28:13):
Yeah, in general, industry has always been quite careful because
it affects the business. Food safety is an important element
for egg business. Egg farmers, they do lots of good
things to produce a very safe product for humans, and
so it all boils down to how that egg is
handled in the kitchen environment. So we just had to
(28:34):
be very careful on how we prepare dishes metal from eggs.
People don't always wash their hands in the kitchen after
handling eggs. After breaking an egg in a pan, they
quickly wipe their hands against the apron if they're wearing apron,
or they just wipe their hand with the kitchen towel.
They could break egg with the knife, which is also
(28:54):
used for cutting vegetables. People can do weird and wonderful
things in the kitchen and wroment and they well, they cook.
Speaker 1 (29:00):
What happens?
Speaker 3 (29:01):
Since you are essentially cross contaminating things in the kitchen.
Speaker 1 (29:04):
The saveest thing is to assume that the outside of
the egg probably has some manilla on it, and that
the inside could also have some manilla inside of it.
Speaker 3 (29:13):
Yeah, so there is a possibility of bacteria being there
on the shell. There is a low possibility of bacteria
being in satin egg. It's not zero, it's low. So
just wash your hands after you are handling eggs and
cook eggs properly.
Speaker 1 (29:30):
All right, thanks for joining us. We hope you had
a shell over time. And if you don't like egg puns,
I'm sorry for all the bad yolks. See you next time.
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