November 18, 2019 • 39 mins
You probably use one everyday: to warm up your lunch, to explode pats of butter or simply to reheat your coffee. But how does a microwave oven work and where does this amazingly useful invention come from? Find out in this episode of Invention!
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Speaker 1 (00:03):
Welcome to Invention, a production of I Heart Radio. Hey,
welcome to Invention. My name is Robert Lamb, and I'm
Joe McCormick. And when are people going to be listening
to this? Thanksgiving hasn't happened yet, right, so you're not
heating up leftovers for a week heating up leftovers, Joe. No,
I'm hoping that people will be inspired by this look
(00:24):
at the microwave and they will cook their entire turkey
in there. That is a horrible idea. I don't do it.
I was just looking it up and there you can
find some uh semi convincing recipes online for how to
cook your entire Thanksgiving turkey in a microwave oven, in
a dirty microwave with a little splatter stains, a nice
clean microwave for a just a wonderful Thanksgiving. Does butter
(00:47):
Ball sell a turkey that comes with its own hot
pocket style sleeve to crisp up the exterior? I don't know.
I don't know about that. But yes, we're gonna be
talking about the microwave oven here on Invention. And the
whole reason that we're launching this in November is because, yeah,
this is a month that is typically associated with food
(01:07):
and feasts, and so we've been looking at some food
based innovations, and really the microwave is is one of
the big ones, uh, in terms of inventions that have
come along in the you know, the last hundred years
and have just changed the way that we think about
the household kitchen totally. Uh. Now, Robert, you mentioned there
are many common mishaps that happened with the microwave, and
(01:31):
and one of the ones I identify with the most
is forgetting that I can't just put a stick of
butter in the microwave and a container to melt the butter.
This happens about once a year where I need, like
suddenly I'm making pancakes for house guests or something something
I don't do very often. I'm like, I'll just melt
the butter in the microwave. I think maybe it's happened
for the last time because I'm talking about it out
(01:52):
loud now, But every time it explodes inside the microwave
and I got to clean up butter everywhere for ten
minutes or however long. Yeah, the stick of butter explosion
is is is something that's very hard to miss. Uh.
You know the sound when you hear it, and then
you think, oh crap, I I did it again. I'm
I have a pretty good system for the times I
need to have melted butter for making pancakes or pop
(02:15):
popovers or something. And I'll take the butter and then
I'll slice it up into smaller pieces, and then I'll
microwave those small pieces of butter in a bowl with
a cover for her, you know, ten fifteen seconds something
like that, and if they need more, I'll give him
another blast. But sometimes I get a little cocky and
I either forget to cover it, or I don't cut
(02:36):
it up as much or give it a little too
much time, and then once more, unexplosion, everything is covered
in butter. And of course there are some other mishaps
that occur from time to time. We've all attempted to
reheat some leftovers or cook a microwave meal, and part
of it will be super hot and part of it
will be almost ice cold. Also, gold leaf, say on
(02:57):
your grandmother's fine china, will turn blue in the microwave oven.
And then of course we've all either burnt popcorn or
cremated a fish stick or something like that. While attempting
to heat something up in the microwave. Generally this is
user air. But but I think the big take home
here is that these are the times when the microwave
oven disappoints us and we take a few moments to
(03:19):
gripe about our microwave oven. But for the most part,
the microwave oven works exceedingly well at the things that
it's good at. It works so well that it is
just a part. It's a part of our kitchen, something
we just completely take for granted, being able to reheat
foods that we cooked the night before, to cook microwave dinners,
(03:39):
or certainly, you know, if you're making pancakes or whatnot,
and you're not getting too cocky with your butter away
to heat something that is going to be utilized in
a recipe for something else that may involve your conventional
or you know, your gas oven, etcetera. Right, I am.
I cook a lot in the house, and sometimes I
can be kind of snobby about the way certain foods
are prepared. So you might think, well, then you don't
(04:01):
use the microwave much, But no, I use the microwave
all the time, and there's tons of stuff that's perfectly
good for. I would not recommend cooking your Thanksgiving turkey
in the microwave. It's uh, it's probably not going to
work out very well. The outside is not gonna look
very appetizing, It'll end up extremely dry, and you're not
going to get very much browning or whatever on the skin.
Has to do with the way the microwave cooks things
(04:22):
that it's not good for. Stuff like that. It's not
good for like big meat roasts and stuff. But for say, uh,
thawing out frozen liquid based things. You know you've got
frozen stock or soup or something like that, it's fantastic, right. Uh.
Certainly popcorn is a great example. You need to microwave popcorn.
There's no better way heat up a little water, et cetera. Now,
(04:43):
when it comes to heating up water, though, there there's
another thing where there can be dangerous associated with with
the way that it heats up food. Like uh, in
certain water containers, you can sometimes get the splash up,
you know, the rapid boil when you dip a spoon
into water that you've heated up in the microwave. If
there are no nucleation points in the water as it
heats up for bubbles to form, so it can gets
kind of superheated but without boiling. Uh So, yeah, that's
(05:07):
a little thing you might have often seen people like
putting a little coffee stir or stick or something is
some kind of non metal spoon into water as they
heat it up, and that's just to help create nucleation
points for bubbles to form so that the water can
boil properly while it's being heated. Interesting, so we're gonna
take our typical approach here to an invention then, in
this case, it's the invention of the microwave oven. Before
(05:29):
we can really appreciate what the microwave oven changes, we
have to talk about what came before. And you know,
given that this is a twentieth century invention, a lot
came before. Everything else in human culinary history came before.
And obviously that means many different forms of oven came first,
earth ovens, ceramic ovens, gas ovens, masonry ovens, toaster ovens,
(05:53):
steam ovens, convection ovens, rotary ovens. At heart, an oven
of any sort is just simply quote, a chamber used
for baking, heating, or drying. That's you're just standard Webster's
definition there, and most of these utilized fire or an
electric heating element, you know, something that will heat the
(06:13):
chamber and therefore heat the food. Connecting to a recent episode,
I wonder if anybody ever made a setup where you
had a turnspit dog to rotate the plate inside the
microave as it goes around. Well, you gotta rotate that
plate one way or another. But the microwave oven the
main way it's different. Uh, you know, regardless of how
neat that little rotating tray happens to be, the main
(06:34):
reason it's different is because it heats food by exposing
the food to electro magnetic radiation in the microwave frequency range.
That's right now, we're gonna be talking a good bit
in these microwave episodes about anti microwave panic. You know,
the terror some people feel at the idea of a
microwave or radiating their food like it's a nuclear test
(06:57):
site in your kitchen. You shouldn't let the word radiat
shan their contribute to this kind of anti microwave panic. Uh.
Most radiation, of course, is harmless to you. The light
coming out of your desk lamp is radiation, and so
in this vein to further demystify the magic of the
microwave cooking box, I think it might be worth a
very quick detour to explain a bit of the underlying
(07:19):
physics here as simply as possible. So, electromagnetic radiation is
the same type of radiation as radio waves, infrared and
visible light UV radiation, X rays, and gamma rays. It's
all the same stuff. It's all photons. What varies to
make the difference between all of these is the frequency,
meaning how fast the waves cycle or oscillate, which can
(07:42):
also be expressed. The same thing can be expressed in
terms of wave length. Faster oscillating waves are shorter, Slower
oscillating waves are longer, and despite the name, microwaves are
actually relatively long low frequency waves. They're called micro waves
because their wavelength is short compared to radio waves, but
microwaves are long compared to pretty much everything else. And
(08:05):
even that appellation sort of it helps place them in
a historical context, right because when you when you see
microwave consciousness emerging among physicists, it's sort of like as
another part of what is generally thought of as the
radio frequency. Now the really dangerous types of radiation we
think of like X rays and gamma rays, the kinds
(08:25):
that cause cancer and radiation poisoning and such. These have
much shorter wavelengths and faster oscillations. Electromagnetic radiation in the
microwave range actually has a lower frequency than visible light
that we see with our eyes. Microwaves are defined as
electromagnetic waves at a frequency greater than three hundred megaherts,
(08:45):
which is three hundred million waves per second, and less
than three hundred giga hurts, which is three hundred billion
waves per second. Uh. And this equates two wavelengths between
about one meter and one millimeter. So when you're trying
to pick sure in microwaves, of course they're invisible, but
you can think of them as waves that are basically
on the human scale. You could measure them with a
(09:07):
ruler or a tape measure. Yeah, I've frequently seen them
described as being about the length of a of a toothbrush.
That's certainly within there. Yeah, between the meter and millimeter scale.
I mean, almost everything that's understand that not understandable, but
everything that's you know, reasonable to measure with your arms
or hands is sort of in the microwave scale. So
how does a microwave oven generate microwaves. Well, it's through
(09:31):
the use of this all important electrical device called a magnetron. Really,
the main thing that operates your microwave oven is a
little device that you can hold in your hand. I'm
not going to try to go into super deep detail
about everything about all the inner workings of the magnetron.
It's especially hard to do without visual aids, but I'll
try to give you the simple version. So, a magnetron
(09:54):
is a device for turning electric current like you get
out of the wall socket into microwave rate ation. And
it consists of a vacuum tube made out of a metal,
often something like copper, with a conductive filament in the
middle of that tube. And then you'll have large permanent magnets,
usually doughnut shaped, on each end of the tube. And
(10:16):
as voltage is applied to the filament that runs through
the middle of this vacuum tube, the filament the currents
running through it and it gets incredibly hot, and then
electrons start to fly off of this negatively charged hot
filament toward the walls of the positively charged tube and
there's so there's an electric field in the vacuum in
(10:37):
between this filament in the middle of the tube and
the walls of the tube. But the magnets at each
end of the tube help shape that flow of electrons
through that vacuum in something kind of like a spiral
or pinwheel shape. And then meanwhile, the metal inner surface
of the tube contains little pockets or cavities, and it's
these cavities that are so important in creating the microwaves.
(11:00):
The spiraling flow of electrons from the through the vacuum
tube rapidly passes over the mouths of those cavities, and
it results in vibration of electrons that creates the electromagnetic
radiation in the microwave spectrum. Uh. So this is how
the waves are created. They're they're emitted by these electrons
as they're like changing energy states. Uh. These microwaves are
(11:22):
projected off the end of an antenna and guided into
the metal lined inter cage of the oven, where they
reflect around. They bounce around inside this and they heat
the food up. So we've got electromagnetic waves bouncing around,
But how does that actually cook the food. The answer
is that almost all foods contain polar molecules. Primarily water molecules,
(11:46):
and what that means is that ht H two O
is slightly positively charged at one end and slightly negatively
charged at the other end. And so as these microwaves
passed by these water molecules, these polar molecules, the molecules
try to rotate to align their poles with the direction
(12:06):
of the electric field produced by each wave. But being waves,
of course, they are rapidly oscillating the direction of that
field back and forth. At two point four gigaherts. These
microwaves passed by billions of times per second, and so
the rapid rotating back and forth of the water molecules
sort of jostles them all around. As they get jostled
(12:28):
around trying to align themselves with this rapidly alternating field.
This manifests is heat. Rapid vibration of molecules, of course,
is heat. Now we should note that some varieties of
microwave oven may introduce additional heating sources, but what we're
talking about here is the standard microwave oven. Are there
like microwaves that have fires inside would be great? Um, well,
(12:50):
they are microwaves that basically involve a heating element and addition, Yeah,
but but but this is the standard. No gas, no
heating element, no fire, just invisible waves agitating water molecules
causing them to vibrate rapidly producing heat. Uh. And this
is why most containers don't you know, microwave safe containers
don't heat up at least, you know, they don't heat
(13:12):
up due to the microwave itself. The food itself may
heat up the dish, etcetera. But the oven does this rapidly.
The oven also does this without requiring any sort of preheating.
And it's not going to warm up your kitchen on
a hot day, or at least not like a four
and fifty degree oven will. I mean, it's the basic
electronic device will heat your room a little bit, right,
(13:32):
I mean the standard oven you've got to think about.
This has to work by heating up the air inside it.
In a microwave, that doesn't matter. In fact, the air
inside a microwave doesn't even get hot except in whatever
way it's like exposed to steam and stuff. Right. And uh,
and also we'll come back to this again. You already
touched on a little bit. But the cooking chamber itself
is surrounded by something like a Faraday cage to prevent
(13:55):
the microwaves from escaping. They're bouncing around in there. They
can't get out. Even in the viewing panel, as everyone's
probably noticed, is covered with a mesh that allows light
to pass through, but not the microwaves. Yeah, and that's
very important. So you can look through because visible light
is small enough of a wavelength to penetrate that mesh,
but the microwaves are too long to penetrate the mesh.
(14:17):
They're stuck inside. And now there might be in modern
microwaves a tiny amount of microwave leakage. This is the
thing that's been we'll talk about this more, probably in
the next episode, but there have been concerns throughout the
history of microwave design about how much microwaves can leak
out of the oven. Modern microwaves are generally very safe.
(14:37):
They keep almost entirely contained. That which leaks out is
not enough to cook too much. So that's the microwave
oven in a nutshell. The next step is going to
be for us to look at the inventor of the
microwave oven. We're gonna take a quick break, but we'll
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O in or text invention to five hundred five hundred.
You know, Robert, I just downloaded Doctor Sleep to listen
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Nice choice for some new Stephen King. Yeah, last year,
I think around this time I listened to The Stand
the long version on Audible and it was it was
like something like fifty hours, but it was great. Now,
(16:46):
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L E dot com slash invention or text Invention to
five hundred five hundred. That's five zero zero dash five
zero zero and we're back. So it's time to talk
about the inventor of the microwave. That's right, we're talking
about Percy Spencer, who lived eight through nineteen seventy. Uh.
(17:28):
This is one of those you know, we we often
find these interesting stories, human stories of the inventors that
are wrapped up in these inventions, and this is certainly
one of the more interesting tales, interesting origin stories of
an inventor. Uh. So, basically a rags to rich's tail.
So he had a really rough early life. Uh. Percy
(17:50):
lost his father eighteen months after his birth, was raised
by his uncle and aunt, and then his uncle died
when he was seven, and he had to quit grammar
school to earned money to help support himself and his aunt.
He worked at a spool mill from age twelve through sixteen,
but he showed an early knack for electrical work, so
(18:10):
he joined the navy at age eighteen and got into
wireless communication, namely radio. He taught himself numerous mathematical and
scientific subjects just you know, consuming the books on his own,
so he was largely self taught. Um. And then he
ends up joining the Raytheon Company in nine Now If
(18:31):
you're familiar with the Raytheon company, you you're probably thinking, oh,
this is this is the enormous uh like defense contractor
and you know, an industrial company, uh, you know, major player.
But at the time when when when Spencer joined Raytheon,
he became its fifth employee. Wow, so he really got
in on the ground floor here. But this would have
(18:52):
been a time when if you were working in uh
in like wireless communication, this was cutting edge stuff and
that would have been highly relevant, not just wireless communication,
but like electromagnetic imaging and stuff would have been extremely
valuable to say international war efforts in national defense, that's right,
and and that was a lot of the work that
(19:13):
was going on with Raytheon at the time. UM he
was extremely successful within the company. He helped develop the
first gaseous rectifier two, which was essential for household radio technology,
and over the course of his career he came to
hold more than a hundred and thirty patents, including patents
for the application of microwave energy to medical uh diathermy,
(19:34):
which is the production of heat and a part of
the body to stimulate to circulation, relief pain, destroy unhealthy tissue,
or to clock bleeding vessels. And during this time, Raytheon
grew enormously as well, uh, you know, becoming the the
major US defense contractor that we know today. Um, but
you can, you can. You can look up a lot
(19:54):
of his patents, a lot of Spencer's patents, and uh
they were up you know, for a variety of highly
technical things such as electrical space discharge device or high
efficiency magnetron, the magnetron we mentioned already, uh, as well
as the likes of For instance, he obtained a two
patent for an improved automobile cigarette lighter, UH, one that
(20:19):
indicates by touch when the element will be hot enough
to light something. Here's a quote from it. An object
of this invention, therefore, is to produce a cigarette lighter
which will give the operator a TecTile indication at the
time when the igniting element of the lighter reaches its
proper temperature. And this could have saved me some pain
in the past. While I was telling you earlier today
(20:41):
about a time when years ago, I was like twenty
years old or something, and I was just sitting in
my car waiting somewhere one time, and I'd never really
used the cigarette lighter in my car. I was like,
I wonder if it works, does it get hot? Because
my car was old. So I pressed it in and
then I pulled it out and I was like, is
it hot? It doesn't look hot, and I pressed my
thumb to it to find out. And that was a
(21:02):
bad day. Well see if that, if this invention had
really taken off, and he could have saved you some time. Uh,
But Spencer is best known for his invention for Raytheon
of the microwave oven um, and most of these patents
that you can look at, you can see that they
are there. You know, they're filed through, filed by Raytheon
with his name on it. Now you might be asking,
(21:22):
wait a minute, why would Raytheon be concerned with coming
up with a new method for cooking food? Right? That
doesn't really seem to fit within their their niche, right.
But in fact, they were not looking for a new
way to create food, right. They were they were looking
into the communication aspects of of of these waves and
the microwaves. And the story goes that Spencer was working
(21:45):
in the lab on a radar set and he noticed
that the candy bar in his pocket had melted, and uh,
you know, others had observed this sort of thing in
the past already. He was not the first individual to
notice that microwaves could, say, melt food or heat up food,
or heat up you know, some sort of organic material.
(22:06):
But he was the first to investigate the matter, and
he ended up experimenting with different foods, including popcorn, including eggs. Yeah,
I read that there was a story where he made
an egg explode on somebody's face. Microwaves, um, you know, yeah,
I'll by exposing them to the magnetron. And then he
built the first microwave oven of sorts by by enclosing
(22:27):
all of this within a metal box and testing various
foods inside of it. I don't know why, but I
just don't have a strong gut feeling that Spencer was
a good cook. Well man, maybe not. You know that
the whole story of the microwaves will continue to explore
is this kind of struggle with what it should be
used for. But but well, we'll get back to that
(22:47):
later on. So ray Beon filed a patent for the
microwave cooking process on October eight n and the Radar
Range hit the market in nineteen six. I love that name,
the Radar Range. What if we still called it that
people would love it more it Uh yeah, they might,
they might, you know, Uh, it's but this thing was
a monster. This thing looked like a robot out of
(23:10):
out of a science fiction film from the period. Uh.
This was a six ft seven and fifty pound beast
of an appliance. But this was just the beginning. This
was just a true, you know, glimpse at the kitchen
of the future. But can you imagine a person at
the time when this very first is a consumer option, thinking, Okay,
I've got ruined my kitchen for a regular oven or
(23:32):
a microwave oven. Which one do I want? Yeah? And
I think that's another issue here too, is this idea
that the microwave oven is going to somehow replace conventional ovens,
that you're not gonna need a gas oven or a
or you know, a heating element oven. But we'll get
into all that in a bit. Obviously, this monster did
(23:53):
not catch catch on right away. Uh. If you weren't
scared away by the idea of cooking food with radiation
in X, then certainly the five thousand dollar price tag
probably did the trick. This would have been equal to
to about fifty thousand if today's dollars, according to APS News,
but they continued, of course, to make improvements. This was
(24:13):
just the first model. The first countertop home model went
on sale in the nineteen fifties for four and by
roughly nine of US households owned a microwave oven. And
we'll talk more about the legacy of the microwave oven
in our second episode on the invention. Well, it's a
(24:34):
funny contrast actually to this behemoth you've gotten in the
early years, because I think it's exactly the size and
portability of a microwave that makes it useful in a
lot of places where you wouldn't even have a regular stove.
These days, I think the dorm rooms. Dorm rooms are
a big one. Yeah, not only the size and the
mobility of the microwave oven, but the degree to which
(24:55):
you can trust it's safety with college students, you know.
You know, when I was in a dorm, you know,
there were a lot of regulations about you can't have candles,
can have incense, or all these things you cannot have
because they're potentially dangerous to you or the entire building.
But the microwave oven is safe now. Spencer continued to
be involved in the evolution of the design and and
(25:17):
and its usages as well. Uh. Consider his nine patent
application which is granted in nineteen fifty one for a
microwave oven cooking method. Uh. And this is the wonderful
intro quote. This invention relates to food cooking, and more
particularly to the cooking of lobsters and thick bodies of
meat by the use of electromagnetic wave energy. It's gonna
(25:39):
get lobsters in their right at the top. Is he
trying to sell it as like a luxe fancy item
that way, or I mean basically, it is a patent
about an improved method for cooking lobsters in a microwave oven. H.
It includes an illustration of the oven with a whole
lobster in it. Um and Uh, yeah it is. It
is all about out lobsters. For instance. There's there's some
(26:02):
more quotes from it. Quote. A further object is to
devise a novel method for broiling lobsters a steal. Further
object is to devise a method for preventing curling of
the tail sections of lobsters during broiling, thereof thereby to
maintain such lobsters substantially constant and thickness during such broiling
and quote, an additional object is to devise a method
(26:23):
which will prevent curling of the tail sections of lobsters
during broiling and will at the same time cause more
effective coupling of the heat energy into the interior of
the tail sections of such lobsters. So much thought about
the tail sections. Yeah, and I want to be clear
about the spencer was talking about microwaving live lobsters. Quote.
(26:44):
It has been found that an electronic oven such as
that described may be utilized for the broiling of live lobsters,
and that when it is done, lobsters may be broiled
in an extremely short time interval on the order of
two minutes, as compared with the approximately eighteen minutes required
by convention broiling techniques. Uh, you know, it's that he's
just making, you know, the argument, you want to broil
(27:04):
some lobsters for dinner, do you want to do it
in eighteen minutes or do you want to want to
do it in two minutes? But the main problem that
he's dealing with in this pattern relates to to a
means of preventing the lobster's tail from curling up underneath
its body. During the microwave and process, as this artificially
shields part of the lobster's body during the cooking process.
(27:26):
You know, one of the things I know as a
cook is exactly the kind of seizing up that causes
like tight curling of of like a shrimp or a
lobster tail or something like that. It's the same thing
when you see like a piece of chickens seizing up
or something, it's usually a pretty good sign that some
some dryness is taking place. And yeah, I guess that's
what he's trying to prevent here. And I don't know
why this horrifies me so much, though, that the the
(27:48):
idea of cooking a live lobster in a microwave. Maybe
it's the Grimlin's uh tie in, you know, the idea
doing like a live gremlin in there. But but it's
ridiculous because certainly the cooking of laws inherently involves the
cooking of live lobsters. And perhaps, you know, perhaps perhaps
part of this is like this weird sort of background
bias against the microwave, uh, you know, you know, or
(28:11):
or that's a sort of background myth making that we
we engage, uh. And when we think about the microwave,
but we'll come back to that later. But what this
says to me is that once he's invented this uh,
Percy spencer is sort of in the microwave zone. Uh,
he's in the radar range zone. And he's just working
the zone for a while, right, Like he's figuring out,
(28:31):
here's every different kind of microwave thing I can do. Yeah.
For instance, he obtained a patent in for a microwave
coffee brewing pot. And note this is not a coffee
pot that goes into a microwave o. And this is
a coffee pot that contains a magnetron that contains a
microwave component to heat the water. It's so funny because
(28:52):
part of what we're doing in these episodes is trying
to dispel unfounded microwave fears. And yet my reaction to
this at a gut level is that's wrong. Well, I mean,
on one level, it's also certain certainly something we're not
used to, like we're used to we have the microwave there, uh,
and if we heat the water for coffee in the microwave,
that's one thing, sure, But the yeah, the idea of
(29:14):
having the magnetron in the coffee, but itself seems strange.
In fact, I could totally do that. I mean at home,
I I usually do pour over coffee. Uh, and yeah,
why not heat the water up in the microwave? I
usually do on the stovetop. But maybe the microwave is
more efficient. I should look into that. All right. On
that note, we're gonna take one more break, and when
we come back we will begin getting into the legacy
(29:35):
of the microwave. Alright, we're back, so it's time to
talk a bit about the the legacy of the microwave oven.
We know that that Percy Spencer has been moving around
in the microwave zone for a while. He's been working
the radar range to broil lobsters to make coffee. But so,
(29:58):
how does the microwave oven take off? How is it
first received, and what happens with the Raytheon company. Well,
obviously we already touched on the fact that it initially
comes out and the technology is large and expensive, and
from there it's about you know, engineering it and getting
it smaller, getting it more affordable, uh, you know, scaling
up production, getting it out there. But but also you
(30:19):
have to there's a certain amount of marketing that has
to take place as well. Uh. But then also you
have to come back to the fact that Raytheon, of
course was originally not an appliance company. So what they
did is they acquired a Manner Refrigeration and then in
nineteen sixty seven, the Raytheon acquired a Manner refrigeration company,
developed the first microwave that sold for under five hundred dollars,
(30:42):
which I believe we alluded to that one earlier. So
this was suddenly you had a microwave that you could
normal people could conceivably purchase and put in their home. Um,
and you know, this is this is I couldn't help
but notice sixty seven two, this is such an interesting
year for change in American culture. You know, it's the
Summer of love. Um. The Mogue synthesizer, uh was you know,
(31:07):
introduced its first production model, and then here's the microwave
as well coming along. You might say that a Mogue
synthesizer is to a cello what the microwave is to
the conventional oven. Yeah yeah, to a certain extent. Um
we say that as lovers of synthesizers. Yeah yeah. But
then also like the synthesizer, it's also kind of a
challenge of figuring out what to do with the synthesizer, Like,
(31:30):
what's the best use of this new technology. Does it
completely replace the piano? No, it does not. It creates
something new that you must, you know, figure out how
to properly utilize exactly right. And as we alluded to earlier,
I think that's both of our attitudes toward the microwave.
It's not that it's a replacement for the oven. It's
also not inferior. It is just a different kind of
(31:51):
tool useful for different jobs. So nineteen seventies hit And
of course also nineteen seventy is the year that that
Percy Spencer dies, so he doesn't really live long enough
to see the real ascension of the microwave oven. But
but but yeah, this is the decade of the microwaves ascension.
(32:12):
The microwave went from being in just ten percent of
American households in nineteen seventy to rivaling conventional oven sales
in nineteen eighty, and they were apparently out selling gas
ranges by ninety five. Uh. These stats, by the way,
are via Jesse Capolt, Kelsey Dean, Madison White, and Helen Selita.
This is at history of Tech dot uh McClerkin dot
(32:35):
org slash microwave is a great microwave information site there
with lots of lots of well sided, well sourced material.
But they point out that a lot of this, uh,
this expansion, that a lot of this acceptance of the
microwave was due to heavy promotion through home and electronics
magazines with a huge emphasis on science education to combat
(32:57):
any concerns over this idea that a microwave was some
sort of a you know, a dangerous hotbed of radiation
that would hurt us. Yeah, and you can still see
those concerns coming through even in the terminology we use,
like the idea of nu king food in the microwave, yeah,
which you know, we're not nuking anything, but we still
use that terminology. So more evidence that we see of
(33:19):
microwave ascendency in the nineties seventies, uh is the number
of microwave cookbooks that we see which featured a lot
of less than amazing sounding recipes. Yeah. There's if you
want to see some examples of this, look up paste magazines.
Thirty horrifying recipes from a seventies microwave cookbook Uh, they're
pretty Uh, they're pretty apolloing. Most of these entries involved
(33:42):
big cuts of meat or some manner of recipe that
seems adapted from a traditional cookbook like a Betty Crocker
or something talking gourmet meals made from scratch cooked in
your microwave oven. Uh, and the results were reportedly less
than awesome. Now, one thing you might be wondering is like,
wait a minute, why is it that food cooked in
(34:03):
a microwave oven is in some cases not as good
as food cooked in a conventional oven. And I would argue,
I think one of the main reasons is going to
be how the exterior of the food is affected by
microwave cooking. So, first of all, I think, especially if
you're cooking like a big cut of meat, something that
would normally happen in the oven, if you cook it
(34:23):
at the right temperature and all that is, you get
nice browning on the outside through the my ard reaction,
which is a very important reaction in food chemistry. It
creates a lot of the sort of meaty, roasty flavors
that we like in all kinds of foods, not just meats.
I mean it's they're in toast. Yeah, we we mentioned
it on our episode about toast and bread. Yeah, and
so the my ard reaction is generally what makes the
(34:45):
exterior of most cooked browned foods appealing. It makes it
look good, it makes it smell good, and makes it
taste good, and you just don't really get that in
the microwave because of the way it cooks. Another thing, though,
is that I would guess in some cases at least
the microwave as a tendency to dry out, especially the
outer layers of food by just steaming off all of
(35:05):
the water molecules from it. So you get outer layers
that might be extremely dry and tough, but not browned. Yeah,
I mean, just by and large, this whole line of thinking,
this sort of you know, gourmet meals from scratch in
your microwave. Um, this is is basically falls into this
idea of of more like replacement the year this is
the only oven you need. You don't need your conventional
(35:25):
oven anymore because you have the microwave oven. But of
course we we have to compare this to how we
actually tend to use the microwave today, now that the
technology has you know, somewhat settled and found its place
in our culture, we use them to heat up microwave
compatible prepackaged meals. For instance, we use them to reheat leftovers,
and we use them to heat portions of recipes, you know,
(35:48):
melt your butter, heats and water defrosting is another major usage. Uh.
And so in many cases we're using it along with
our other heating methods to cook a meal as well.
Like I was showing my son in our own kitchen
that we have, uh, we have three different means of
of of heating food. We have the microwave using uh
uh you know, the magnetron. We have a gas powered stove,
(36:11):
and then we also have the toaster oven with its
you know, electric heating element. So it's interesting how we'll
sometimes use all three of these in the preparation of
a single meal. But the prepackaged microwave meals I think
are a big one as well. And I was reading
a little bit about this. According to BBC's The Rise
of the ready Meal by Denise Winterman two thousand thirteen article,
(36:34):
companies like Swanson, before the microwave took hold, had already
influenced our tastes with ready made meals. The TV dinner
was already here yeah, you get those. You you of
course would make those in a conventional oven. And I
think I recall, if I'm not wrong, that those originally
came about mainly because like turkey, uh, agricultural concerns, We're
(36:56):
trying to figure out ways to sell turkey outside of
thanks Giving, and they're like, we can make turkey TV
dinners to sell people to heat up in their ovens
without cooking. Yeah, and and also I guess we should
point out you had the stovetop popcorn as well. Oh yeah,
So so basically we're already down with the idea of
fast prepackaged meals, right, no preparation, just pop it in
(37:18):
and said in a microwave just makes it that much easier. Exactly.
It's like a logical extension of the TV dinner concept.
And in fact, I think it's exactly the way in
which it's an extension of that that sometimes I think
the microwave is used as a kind of metaphor or
shorthand for I don't know, for something about consumerism. Do
you do you detect this, Yeah, yeah, it is. It
(37:40):
is often the place where we simply heat up a
prepackaged meal. It is the convenience aspect of it. And
perhaps I don't know, I feel like maybe when I
was a kid, maybe there were fewer healthy options for
microwave meals. Um. Nowadays you can get a lot of
really you know, quite good food that you can heat
(38:01):
up in the microwave. Um or you can do I mean,
you can use a microwave to steam broccoli. You can
use microwave all kinds of stuff. Oh yeah, yeah, outside
of just prepackaged meals, you can you can certainly do
a lot with it that is not cooking a whole turkey.
So you know, not to not to imply that that
it's just there's a you know, it's either use it
(38:21):
to try and cook everything or use it to cook
prepackaged meals. There's a it's a it's a very useful
tool in the modern kitchen. It is a part of
the modern kitchen. Look at us here rehabilitating the image
of the microwave, well, I mean, on one hand, you know,
it still has to deal with with image issues. There's
still still, as we'll discuss in the next episode, encounter
people spreading untruths about the microwave, slandering the microwave, and
(38:46):
at the same time, like the microwave is everywhere. The
microwave is one. The microwave is nearly ubiquitous. I guess
it doesn't really need our help, right, um, I mean
the microwave is is waiting for you in your local
gas station, ready for you to to heat up some
sort of prepackaged nonsense that you just purchased. Well, let's
(39:06):
come back next time and heat up that nonsense in
the meantime. If you want to check out other episodes
of Invention, head on over ton invention pod dot com.
You'll also find the show wherever you get your podcasts.
If you want to support this show and uh see
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(39:28):
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If you would like to give us feedback on this
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For more podcasts from my heart Radio because the iHeart
(39:50):
Radio app, Apple Podcasts, or wherever you listen to your
favorite shows
Welcome to Invention, a production of I Heart Radio. Hey,
welcome to Invention. My name is Robert Lamb, and I'm
Joe McCormick. And when are people going to be listening
to this? Thanksgiving hasn't happened yet, right, so you're not
heating up leftovers for a week heating up leftovers, Joe. No,
I'm hoping that people will be inspired by this look
(00:24):
at the microwave and they will cook their entire turkey
in there. That is a horrible idea. I don't do it.
I was just looking it up and there you can
find some uh semi convincing recipes online for how to
cook your entire Thanksgiving turkey in a microwave oven, in
a dirty microwave with a little splatter stains, a nice
clean microwave for a just a wonderful Thanksgiving. Does butter
(00:47):
Ball sell a turkey that comes with its own hot
pocket style sleeve to crisp up the exterior? I don't know.
I don't know about that. But yes, we're gonna be
talking about the microwave oven here on Invention. And the
whole reason that we're launching this in November is because, yeah,
this is a month that is typically associated with food
(01:07):
and feasts, and so we've been looking at some food
based innovations, and really the microwave is is one of
the big ones, uh, in terms of inventions that have
come along in the you know, the last hundred years
and have just changed the way that we think about
the household kitchen totally. Uh. Now, Robert, you mentioned there
are many common mishaps that happened with the microwave, and
(01:31):
and one of the ones I identify with the most
is forgetting that I can't just put a stick of
butter in the microwave and a container to melt the butter.
This happens about once a year where I need, like
suddenly I'm making pancakes for house guests or something something
I don't do very often. I'm like, I'll just melt
the butter in the microwave. I think maybe it's happened
for the last time because I'm talking about it out
(01:52):
loud now, But every time it explodes inside the microwave
and I got to clean up butter everywhere for ten
minutes or however long. Yeah, the stick of butter explosion
is is is something that's very hard to miss. Uh.
You know the sound when you hear it, and then
you think, oh crap, I I did it again. I'm
I have a pretty good system for the times I
need to have melted butter for making pancakes or pop
(02:15):
popovers or something. And I'll take the butter and then
I'll slice it up into smaller pieces, and then I'll
microwave those small pieces of butter in a bowl with
a cover for her, you know, ten fifteen seconds something
like that, and if they need more, I'll give him
another blast. But sometimes I get a little cocky and
I either forget to cover it, or I don't cut
(02:36):
it up as much or give it a little too
much time, and then once more, unexplosion, everything is covered
in butter. And of course there are some other mishaps
that occur from time to time. We've all attempted to
reheat some leftovers or cook a microwave meal, and part
of it will be super hot and part of it
will be almost ice cold. Also, gold leaf, say on
(02:57):
your grandmother's fine china, will turn blue in the microwave oven.
And then of course we've all either burnt popcorn or
cremated a fish stick or something like that. While attempting
to heat something up in the microwave. Generally this is
user air. But but I think the big take home
here is that these are the times when the microwave
oven disappoints us and we take a few moments to
(03:19):
gripe about our microwave oven. But for the most part,
the microwave oven works exceedingly well at the things that
it's good at. It works so well that it is
just a part. It's a part of our kitchen, something
we just completely take for granted, being able to reheat
foods that we cooked the night before, to cook microwave dinners,
(03:39):
or certainly, you know, if you're making pancakes or whatnot,
and you're not getting too cocky with your butter away
to heat something that is going to be utilized in
a recipe for something else that may involve your conventional
or you know, your gas oven, etcetera. Right, I am.
I cook a lot in the house, and sometimes I
can be kind of snobby about the way certain foods
are prepared. So you might think, well, then you don't
(04:01):
use the microwave much, But no, I use the microwave
all the time, and there's tons of stuff that's perfectly
good for. I would not recommend cooking your Thanksgiving turkey
in the microwave. It's uh, it's probably not going to
work out very well. The outside is not gonna look
very appetizing, It'll end up extremely dry, and you're not
going to get very much browning or whatever on the skin.
Has to do with the way the microwave cooks things
(04:22):
that it's not good for. Stuff like that. It's not
good for like big meat roasts and stuff. But for say, uh,
thawing out frozen liquid based things. You know you've got
frozen stock or soup or something like that, it's fantastic, right. Uh.
Certainly popcorn is a great example. You need to microwave popcorn.
There's no better way heat up a little water, et cetera. Now,
(04:43):
when it comes to heating up water, though, there there's
another thing where there can be dangerous associated with with
the way that it heats up food. Like uh, in
certain water containers, you can sometimes get the splash up,
you know, the rapid boil when you dip a spoon
into water that you've heated up in the microwave. If
there are no nucleation points in the water as it
heats up for bubbles to form, so it can gets
kind of superheated but without boiling. Uh So, yeah, that's
(05:07):
a little thing you might have often seen people like
putting a little coffee stir or stick or something is
some kind of non metal spoon into water as they
heat it up, and that's just to help create nucleation
points for bubbles to form so that the water can
boil properly while it's being heated. Interesting, so we're gonna
take our typical approach here to an invention then, in
this case, it's the invention of the microwave oven. Before
(05:29):
we can really appreciate what the microwave oven changes, we
have to talk about what came before. And you know,
given that this is a twentieth century invention, a lot
came before. Everything else in human culinary history came before.
And obviously that means many different forms of oven came first,
earth ovens, ceramic ovens, gas ovens, masonry ovens, toaster ovens,
(05:53):
steam ovens, convection ovens, rotary ovens. At heart, an oven
of any sort is just simply quote, a chamber used
for baking, heating, or drying. That's you're just standard Webster's
definition there, and most of these utilized fire or an
electric heating element, you know, something that will heat the
(06:13):
chamber and therefore heat the food. Connecting to a recent episode,
I wonder if anybody ever made a setup where you
had a turnspit dog to rotate the plate inside the
microave as it goes around. Well, you gotta rotate that
plate one way or another. But the microwave oven the
main way it's different. Uh, you know, regardless of how
neat that little rotating tray happens to be, the main
(06:34):
reason it's different is because it heats food by exposing
the food to electro magnetic radiation in the microwave frequency range.
That's right now, we're gonna be talking a good bit
in these microwave episodes about anti microwave panic. You know,
the terror some people feel at the idea of a
microwave or radiating their food like it's a nuclear test
(06:57):
site in your kitchen. You shouldn't let the word radiat
shan their contribute to this kind of anti microwave panic. Uh.
Most radiation, of course, is harmless to you. The light
coming out of your desk lamp is radiation, and so
in this vein to further demystify the magic of the
microwave cooking box, I think it might be worth a
very quick detour to explain a bit of the underlying
(07:19):
physics here as simply as possible. So, electromagnetic radiation is
the same type of radiation as radio waves, infrared and
visible light UV radiation, X rays, and gamma rays. It's
all the same stuff. It's all photons. What varies to
make the difference between all of these is the frequency,
meaning how fast the waves cycle or oscillate, which can
(07:42):
also be expressed. The same thing can be expressed in
terms of wave length. Faster oscillating waves are shorter, Slower
oscillating waves are longer, and despite the name, microwaves are
actually relatively long low frequency waves. They're called micro waves
because their wavelength is short compared to radio waves, but
microwaves are long compared to pretty much everything else. And
(08:05):
even that appellation sort of it helps place them in
a historical context, right because when you when you see
microwave consciousness emerging among physicists, it's sort of like as
another part of what is generally thought of as the
radio frequency. Now the really dangerous types of radiation we
think of like X rays and gamma rays, the kinds
(08:25):
that cause cancer and radiation poisoning and such. These have
much shorter wavelengths and faster oscillations. Electromagnetic radiation in the
microwave range actually has a lower frequency than visible light
that we see with our eyes. Microwaves are defined as
electromagnetic waves at a frequency greater than three hundred megaherts,
(08:45):
which is three hundred million waves per second, and less
than three hundred giga hurts, which is three hundred billion
waves per second. Uh. And this equates two wavelengths between
about one meter and one millimeter. So when you're trying
to pick sure in microwaves, of course they're invisible, but
you can think of them as waves that are basically
on the human scale. You could measure them with a
(09:07):
ruler or a tape measure. Yeah, I've frequently seen them
described as being about the length of a of a toothbrush.
That's certainly within there. Yeah, between the meter and millimeter scale.
I mean, almost everything that's understand that not understandable, but
everything that's you know, reasonable to measure with your arms
or hands is sort of in the microwave scale. So
how does a microwave oven generate microwaves. Well, it's through
(09:31):
the use of this all important electrical device called a magnetron. Really,
the main thing that operates your microwave oven is a
little device that you can hold in your hand. I'm
not going to try to go into super deep detail
about everything about all the inner workings of the magnetron.
It's especially hard to do without visual aids, but I'll
try to give you the simple version. So, a magnetron
(09:54):
is a device for turning electric current like you get
out of the wall socket into microwave rate ation. And
it consists of a vacuum tube made out of a metal,
often something like copper, with a conductive filament in the
middle of that tube. And then you'll have large permanent magnets,
usually doughnut shaped, on each end of the tube. And
(10:16):
as voltage is applied to the filament that runs through
the middle of this vacuum tube, the filament the currents
running through it and it gets incredibly hot, and then
electrons start to fly off of this negatively charged hot
filament toward the walls of the positively charged tube and
there's so there's an electric field in the vacuum in
(10:37):
between this filament in the middle of the tube and
the walls of the tube. But the magnets at each
end of the tube help shape that flow of electrons
through that vacuum in something kind of like a spiral
or pinwheel shape. And then meanwhile, the metal inner surface
of the tube contains little pockets or cavities, and it's
these cavities that are so important in creating the microwaves.
(11:00):
The spiraling flow of electrons from the through the vacuum
tube rapidly passes over the mouths of those cavities, and
it results in vibration of electrons that creates the electromagnetic
radiation in the microwave spectrum. Uh. So this is how
the waves are created. They're they're emitted by these electrons
as they're like changing energy states. Uh. These microwaves are
(11:22):
projected off the end of an antenna and guided into
the metal lined inter cage of the oven, where they
reflect around. They bounce around inside this and they heat
the food up. So we've got electromagnetic waves bouncing around,
But how does that actually cook the food. The answer
is that almost all foods contain polar molecules. Primarily water molecules,
(11:46):
and what that means is that ht H two O
is slightly positively charged at one end and slightly negatively
charged at the other end. And so as these microwaves
passed by these water molecules, these polar molecules, the molecules
try to rotate to align their poles with the direction
(12:06):
of the electric field produced by each wave. But being waves,
of course, they are rapidly oscillating the direction of that
field back and forth. At two point four gigaherts. These
microwaves passed by billions of times per second, and so
the rapid rotating back and forth of the water molecules
sort of jostles them all around. As they get jostled
(12:28):
around trying to align themselves with this rapidly alternating field.
This manifests is heat. Rapid vibration of molecules, of course,
is heat. Now we should note that some varieties of
microwave oven may introduce additional heating sources, but what we're
talking about here is the standard microwave oven. Are there
like microwaves that have fires inside would be great? Um, well,
(12:50):
they are microwaves that basically involve a heating element and addition, Yeah,
but but but this is the standard. No gas, no
heating element, no fire, just invisible waves agitating water molecules
causing them to vibrate rapidly producing heat. Uh. And this
is why most containers don't you know, microwave safe containers
don't heat up at least, you know, they don't heat
(13:12):
up due to the microwave itself. The food itself may
heat up the dish, etcetera. But the oven does this rapidly.
The oven also does this without requiring any sort of preheating.
And it's not going to warm up your kitchen on
a hot day, or at least not like a four
and fifty degree oven will. I mean, it's the basic
electronic device will heat your room a little bit, right,
(13:32):
I mean the standard oven you've got to think about.
This has to work by heating up the air inside it.
In a microwave, that doesn't matter. In fact, the air
inside a microwave doesn't even get hot except in whatever
way it's like exposed to steam and stuff. Right. And uh,
and also we'll come back to this again. You already
touched on a little bit. But the cooking chamber itself
is surrounded by something like a Faraday cage to prevent
(13:55):
the microwaves from escaping. They're bouncing around in there. They
can't get out. Even in the viewing panel, as everyone's
probably noticed, is covered with a mesh that allows light
to pass through, but not the microwaves. Yeah, and that's
very important. So you can look through because visible light
is small enough of a wavelength to penetrate that mesh,
but the microwaves are too long to penetrate the mesh.
(14:17):
They're stuck inside. And now there might be in modern
microwaves a tiny amount of microwave leakage. This is the
thing that's been we'll talk about this more, probably in
the next episode, but there have been concerns throughout the
history of microwave design about how much microwaves can leak
out of the oven. Modern microwaves are generally very safe.
(14:37):
They keep almost entirely contained. That which leaks out is
not enough to cook too much. So that's the microwave
oven in a nutshell. The next step is going to
be for us to look at the inventor of the
microwave oven. We're gonna take a quick break, but we'll
be right back. Hey, everybody, audible has the world's largest
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(16:25):
O in or text invention to five hundred five hundred.
You know, Robert, I just downloaded Doctor Sleep to listen
to on Audible. I'm very excited to get into that.
Nice choice for some new Stephen King. Yeah, last year,
I think around this time I listened to The Stand
the long version on Audible and it was it was
like something like fifty hours, but it was great. Now,
(16:46):
I always really enjoy revisiting the works of Karl Sagan,
and so this is is super exciting that there's just
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L E dot com slash invention or text Invention to
five hundred five hundred. That's five zero zero dash five
zero zero and we're back. So it's time to talk
about the inventor of the microwave. That's right, we're talking
about Percy Spencer, who lived eight through nineteen seventy. Uh.
(17:28):
This is one of those you know, we we often
find these interesting stories, human stories of the inventors that
are wrapped up in these inventions, and this is certainly
one of the more interesting tales, interesting origin stories of
an inventor. Uh. So, basically a rags to rich's tail.
So he had a really rough early life. Uh. Percy
(17:50):
lost his father eighteen months after his birth, was raised
by his uncle and aunt, and then his uncle died
when he was seven, and he had to quit grammar
school to earned money to help support himself and his aunt.
He worked at a spool mill from age twelve through sixteen,
but he showed an early knack for electrical work, so
(18:10):
he joined the navy at age eighteen and got into
wireless communication, namely radio. He taught himself numerous mathematical and
scientific subjects just you know, consuming the books on his own,
so he was largely self taught. Um. And then he
ends up joining the Raytheon Company in nine Now If
(18:31):
you're familiar with the Raytheon company, you you're probably thinking, oh,
this is this is the enormous uh like defense contractor
and you know, an industrial company, uh, you know, major player.
But at the time when when when Spencer joined Raytheon,
he became its fifth employee. Wow, so he really got
in on the ground floor here. But this would have
(18:52):
been a time when if you were working in uh
in like wireless communication, this was cutting edge stuff and
that would have been highly relevant, not just wireless communication,
but like electromagnetic imaging and stuff would have been extremely
valuable to say international war efforts in national defense, that's right,
and and that was a lot of the work that
(19:13):
was going on with Raytheon at the time. UM he
was extremely successful within the company. He helped develop the
first gaseous rectifier two, which was essential for household radio technology,
and over the course of his career he came to
hold more than a hundred and thirty patents, including patents
for the application of microwave energy to medical uh diathermy,
(19:34):
which is the production of heat and a part of
the body to stimulate to circulation, relief pain, destroy unhealthy tissue,
or to clock bleeding vessels. And during this time, Raytheon
grew enormously as well, uh, you know, becoming the the
major US defense contractor that we know today. Um, but
you can, you can. You can look up a lot
(19:54):
of his patents, a lot of Spencer's patents, and uh
they were up you know, for a variety of highly
technical things such as electrical space discharge device or high
efficiency magnetron, the magnetron we mentioned already, uh, as well
as the likes of For instance, he obtained a two
patent for an improved automobile cigarette lighter, UH, one that
(20:19):
indicates by touch when the element will be hot enough
to light something. Here's a quote from it. An object
of this invention, therefore, is to produce a cigarette lighter
which will give the operator a TecTile indication at the
time when the igniting element of the lighter reaches its
proper temperature. And this could have saved me some pain
in the past. While I was telling you earlier today
(20:41):
about a time when years ago, I was like twenty
years old or something, and I was just sitting in
my car waiting somewhere one time, and I'd never really
used the cigarette lighter in my car. I was like,
I wonder if it works, does it get hot? Because
my car was old. So I pressed it in and
then I pulled it out and I was like, is
it hot? It doesn't look hot, and I pressed my
thumb to it to find out. And that was a
(21:02):
bad day. Well see if that, if this invention had
really taken off, and he could have saved you some time. Uh,
But Spencer is best known for his invention for Raytheon
of the microwave oven um, and most of these patents
that you can look at, you can see that they
are there. You know, they're filed through, filed by Raytheon
with his name on it. Now you might be asking,
(21:22):
wait a minute, why would Raytheon be concerned with coming
up with a new method for cooking food? Right? That
doesn't really seem to fit within their their niche, right.
But in fact, they were not looking for a new
way to create food, right. They were they were looking
into the communication aspects of of of these waves and
the microwaves. And the story goes that Spencer was working
(21:45):
in the lab on a radar set and he noticed
that the candy bar in his pocket had melted, and uh,
you know, others had observed this sort of thing in
the past already. He was not the first individual to
notice that microwaves could, say, melt food or heat up food,
or heat up you know, some sort of organic material.
(22:06):
But he was the first to investigate the matter, and
he ended up experimenting with different foods, including popcorn, including eggs. Yeah,
I read that there was a story where he made
an egg explode on somebody's face. Microwaves, um, you know, yeah,
I'll by exposing them to the magnetron. And then he
built the first microwave oven of sorts by by enclosing
(22:27):
all of this within a metal box and testing various
foods inside of it. I don't know why, but I
just don't have a strong gut feeling that Spencer was
a good cook. Well man, maybe not. You know that
the whole story of the microwaves will continue to explore
is this kind of struggle with what it should be
used for. But but well, we'll get back to that
(22:47):
later on. So ray Beon filed a patent for the
microwave cooking process on October eight n and the Radar
Range hit the market in nineteen six. I love that name,
the Radar Range. What if we still called it that
people would love it more it Uh yeah, they might,
they might, you know, Uh, it's but this thing was
a monster. This thing looked like a robot out of
(23:10):
out of a science fiction film from the period. Uh.
This was a six ft seven and fifty pound beast
of an appliance. But this was just the beginning. This
was just a true, you know, glimpse at the kitchen
of the future. But can you imagine a person at
the time when this very first is a consumer option, thinking, Okay,
I've got ruined my kitchen for a regular oven or
(23:32):
a microwave oven. Which one do I want? Yeah? And
I think that's another issue here too, is this idea
that the microwave oven is going to somehow replace conventional ovens,
that you're not gonna need a gas oven or a
or you know, a heating element oven. But we'll get
into all that in a bit. Obviously, this monster did
(23:53):
not catch catch on right away. Uh. If you weren't
scared away by the idea of cooking food with radiation
in X, then certainly the five thousand dollar price tag
probably did the trick. This would have been equal to
to about fifty thousand if today's dollars, according to APS News,
but they continued, of course, to make improvements. This was
(24:13):
just the first model. The first countertop home model went
on sale in the nineteen fifties for four and by
roughly nine of US households owned a microwave oven. And
we'll talk more about the legacy of the microwave oven
in our second episode on the invention. Well, it's a
(24:34):
funny contrast actually to this behemoth you've gotten in the
early years, because I think it's exactly the size and
portability of a microwave that makes it useful in a
lot of places where you wouldn't even have a regular stove.
These days, I think the dorm rooms. Dorm rooms are
a big one. Yeah, not only the size and the
mobility of the microwave oven, but the degree to which
(24:55):
you can trust it's safety with college students, you know.
You know, when I was in a dorm, you know,
there were a lot of regulations about you can't have candles,
can have incense, or all these things you cannot have
because they're potentially dangerous to you or the entire building.
But the microwave oven is safe now. Spencer continued to
be involved in the evolution of the design and and
(25:17):
and its usages as well. Uh. Consider his nine patent
application which is granted in nineteen fifty one for a
microwave oven cooking method. Uh. And this is the wonderful
intro quote. This invention relates to food cooking, and more
particularly to the cooking of lobsters and thick bodies of
meat by the use of electromagnetic wave energy. It's gonna
(25:39):
get lobsters in their right at the top. Is he
trying to sell it as like a luxe fancy item
that way, or I mean basically, it is a patent
about an improved method for cooking lobsters in a microwave oven. H.
It includes an illustration of the oven with a whole
lobster in it. Um and Uh, yeah it is. It
is all about out lobsters. For instance. There's there's some
(26:02):
more quotes from it. Quote. A further object is to
devise a novel method for broiling lobsters a steal. Further
object is to devise a method for preventing curling of
the tail sections of lobsters during broiling, thereof thereby to
maintain such lobsters substantially constant and thickness during such broiling
and quote, an additional object is to devise a method
(26:23):
which will prevent curling of the tail sections of lobsters
during broiling and will at the same time cause more
effective coupling of the heat energy into the interior of
the tail sections of such lobsters. So much thought about
the tail sections. Yeah, and I want to be clear
about the spencer was talking about microwaving live lobsters. Quote.
(26:44):
It has been found that an electronic oven such as
that described may be utilized for the broiling of live lobsters,
and that when it is done, lobsters may be broiled
in an extremely short time interval on the order of
two minutes, as compared with the approximately eighteen minutes required
by convention broiling techniques. Uh, you know, it's that he's
just making, you know, the argument, you want to broil
(27:04):
some lobsters for dinner, do you want to do it
in eighteen minutes or do you want to want to
do it in two minutes? But the main problem that
he's dealing with in this pattern relates to to a
means of preventing the lobster's tail from curling up underneath
its body. During the microwave and process, as this artificially
shields part of the lobster's body during the cooking process.
(27:26):
You know, one of the things I know as a
cook is exactly the kind of seizing up that causes
like tight curling of of like a shrimp or a
lobster tail or something like that. It's the same thing
when you see like a piece of chickens seizing up
or something, it's usually a pretty good sign that some
some dryness is taking place. And yeah, I guess that's
what he's trying to prevent here. And I don't know
why this horrifies me so much, though, that the the
(27:48):
idea of cooking a live lobster in a microwave. Maybe
it's the Grimlin's uh tie in, you know, the idea
doing like a live gremlin in there. But but it's
ridiculous because certainly the cooking of laws inherently involves the
cooking of live lobsters. And perhaps, you know, perhaps perhaps
part of this is like this weird sort of background
bias against the microwave, uh, you know, you know, or
(28:11):
or that's a sort of background myth making that we
we engage, uh. And when we think about the microwave,
but we'll come back to that later. But what this
says to me is that once he's invented this uh,
Percy spencer is sort of in the microwave zone. Uh,
he's in the radar range zone. And he's just working
the zone for a while, right, Like he's figuring out,
(28:31):
here's every different kind of microwave thing I can do. Yeah.
For instance, he obtained a patent in for a microwave
coffee brewing pot. And note this is not a coffee
pot that goes into a microwave o. And this is
a coffee pot that contains a magnetron that contains a
microwave component to heat the water. It's so funny because
(28:52):
part of what we're doing in these episodes is trying
to dispel unfounded microwave fears. And yet my reaction to
this at a gut level is that's wrong. Well, I mean,
on one level, it's also certain certainly something we're not
used to, like we're used to we have the microwave there, uh,
and if we heat the water for coffee in the microwave,
that's one thing, sure, But the yeah, the idea of
(29:14):
having the magnetron in the coffee, but itself seems strange.
In fact, I could totally do that. I mean at home,
I I usually do pour over coffee. Uh, and yeah,
why not heat the water up in the microwave? I
usually do on the stovetop. But maybe the microwave is
more efficient. I should look into that. All right. On
that note, we're gonna take one more break, and when
we come back we will begin getting into the legacy
(29:35):
of the microwave. Alright, we're back, so it's time to
talk a bit about the the legacy of the microwave oven.
We know that that Percy Spencer has been moving around
in the microwave zone for a while. He's been working
the radar range to broil lobsters to make coffee. But so,
(29:58):
how does the microwave oven take off? How is it
first received, and what happens with the Raytheon company. Well,
obviously we already touched on the fact that it initially
comes out and the technology is large and expensive, and
from there it's about you know, engineering it and getting
it smaller, getting it more affordable, uh, you know, scaling
up production, getting it out there. But but also you
(30:19):
have to there's a certain amount of marketing that has
to take place as well. Uh. But then also you
have to come back to the fact that Raytheon, of
course was originally not an appliance company. So what they
did is they acquired a Manner Refrigeration and then in
nineteen sixty seven, the Raytheon acquired a Manner refrigeration company,
developed the first microwave that sold for under five hundred dollars,
(30:42):
which I believe we alluded to that one earlier. So
this was suddenly you had a microwave that you could
normal people could conceivably purchase and put in their home. Um,
and you know, this is this is I couldn't help
but notice sixty seven two, this is such an interesting
year for change in American culture. You know, it's the
Summer of love. Um. The Mogue synthesizer, uh was you know,
(31:07):
introduced its first production model, and then here's the microwave
as well coming along. You might say that a Mogue
synthesizer is to a cello what the microwave is to
the conventional oven. Yeah yeah, to a certain extent. Um
we say that as lovers of synthesizers. Yeah yeah. But
then also like the synthesizer, it's also kind of a
challenge of figuring out what to do with the synthesizer, Like,
(31:30):
what's the best use of this new technology. Does it
completely replace the piano? No, it does not. It creates
something new that you must, you know, figure out how
to properly utilize exactly right. And as we alluded to earlier,
I think that's both of our attitudes toward the microwave.
It's not that it's a replacement for the oven. It's
also not inferior. It is just a different kind of
(31:51):
tool useful for different jobs. So nineteen seventies hit And
of course also nineteen seventy is the year that that
Percy Spencer dies, so he doesn't really live long enough
to see the real ascension of the microwave oven. But
but but yeah, this is the decade of the microwaves ascension.
(32:12):
The microwave went from being in just ten percent of
American households in nineteen seventy to rivaling conventional oven sales
in nineteen eighty, and they were apparently out selling gas
ranges by ninety five. Uh. These stats, by the way,
are via Jesse Capolt, Kelsey Dean, Madison White, and Helen Selita.
This is at history of Tech dot uh McClerkin dot
(32:35):
org slash microwave is a great microwave information site there
with lots of lots of well sided, well sourced material.
But they point out that a lot of this, uh,
this expansion, that a lot of this acceptance of the
microwave was due to heavy promotion through home and electronics
magazines with a huge emphasis on science education to combat
(32:57):
any concerns over this idea that a microwave was some
sort of a you know, a dangerous hotbed of radiation
that would hurt us. Yeah, and you can still see
those concerns coming through even in the terminology we use,
like the idea of nu king food in the microwave, yeah,
which you know, we're not nuking anything, but we still
use that terminology. So more evidence that we see of
(33:19):
microwave ascendency in the nineties seventies, uh is the number
of microwave cookbooks that we see which featured a lot
of less than amazing sounding recipes. Yeah. There's if you
want to see some examples of this, look up paste magazines.
Thirty horrifying recipes from a seventies microwave cookbook Uh, they're
pretty Uh, they're pretty apolloing. Most of these entries involved
(33:42):
big cuts of meat or some manner of recipe that
seems adapted from a traditional cookbook like a Betty Crocker
or something talking gourmet meals made from scratch cooked in
your microwave oven. Uh, and the results were reportedly less
than awesome. Now, one thing you might be wondering is like,
wait a minute, why is it that food cooked in
(34:03):
a microwave oven is in some cases not as good
as food cooked in a conventional oven. And I would argue,
I think one of the main reasons is going to
be how the exterior of the food is affected by
microwave cooking. So, first of all, I think, especially if
you're cooking like a big cut of meat, something that
would normally happen in the oven, if you cook it
(34:23):
at the right temperature and all that is, you get
nice browning on the outside through the my ard reaction,
which is a very important reaction in food chemistry. It
creates a lot of the sort of meaty, roasty flavors
that we like in all kinds of foods, not just meats.
I mean it's they're in toast. Yeah, we we mentioned
it on our episode about toast and bread. Yeah, and
so the my ard reaction is generally what makes the
(34:45):
exterior of most cooked browned foods appealing. It makes it
look good, it makes it smell good, and makes it
taste good, and you just don't really get that in
the microwave because of the way it cooks. Another thing, though,
is that I would guess in some cases at least
the microwave as a tendency to dry out, especially the
outer layers of food by just steaming off all of
(35:05):
the water molecules from it. So you get outer layers
that might be extremely dry and tough, but not browned. Yeah,
I mean, just by and large, this whole line of thinking,
this sort of you know, gourmet meals from scratch in
your microwave. Um, this is is basically falls into this
idea of of more like replacement the year this is
the only oven you need. You don't need your conventional
(35:25):
oven anymore because you have the microwave oven. But of
course we we have to compare this to how we
actually tend to use the microwave today, now that the
technology has you know, somewhat settled and found its place
in our culture, we use them to heat up microwave
compatible prepackaged meals. For instance, we use them to reheat leftovers,
and we use them to heat portions of recipes, you know,
(35:48):
melt your butter, heats and water defrosting is another major usage. Uh.
And so in many cases we're using it along with
our other heating methods to cook a meal as well.
Like I was showing my son in our own kitchen
that we have, uh, we have three different means of
of of heating food. We have the microwave using uh
uh you know, the magnetron. We have a gas powered stove,
(36:11):
and then we also have the toaster oven with its
you know, electric heating element. So it's interesting how we'll
sometimes use all three of these in the preparation of
a single meal. But the prepackaged microwave meals I think
are a big one as well. And I was reading
a little bit about this. According to BBC's The Rise
of the ready Meal by Denise Winterman two thousand thirteen article,
(36:34):
companies like Swanson, before the microwave took hold, had already
influenced our tastes with ready made meals. The TV dinner
was already here yeah, you get those. You you of
course would make those in a conventional oven. And I
think I recall, if I'm not wrong, that those originally
came about mainly because like turkey, uh, agricultural concerns, We're
(36:56):
trying to figure out ways to sell turkey outside of
thanks Giving, and they're like, we can make turkey TV
dinners to sell people to heat up in their ovens
without cooking. Yeah, and and also I guess we should
point out you had the stovetop popcorn as well. Oh yeah,
So so basically we're already down with the idea of
fast prepackaged meals, right, no preparation, just pop it in
(37:18):
and said in a microwave just makes it that much easier. Exactly.
It's like a logical extension of the TV dinner concept.
And in fact, I think it's exactly the way in
which it's an extension of that that sometimes I think
the microwave is used as a kind of metaphor or
shorthand for I don't know, for something about consumerism. Do
you do you detect this, Yeah, yeah, it is. It
(37:40):
is often the place where we simply heat up a
prepackaged meal. It is the convenience aspect of it. And
perhaps I don't know, I feel like maybe when I
was a kid, maybe there were fewer healthy options for
microwave meals. Um. Nowadays you can get a lot of
really you know, quite good food that you can heat
(38:01):
up in the microwave. Um or you can do I mean,
you can use a microwave to steam broccoli. You can
use microwave all kinds of stuff. Oh yeah, yeah, outside
of just prepackaged meals, you can you can certainly do
a lot with it that is not cooking a whole turkey.
So you know, not to not to imply that that
it's just there's a you know, it's either use it
(38:21):
to try and cook everything or use it to cook
prepackaged meals. There's a it's a it's a very useful
tool in the modern kitchen. It is a part of
the modern kitchen. Look at us here rehabilitating the image
of the microwave, well, I mean, on one hand, you know,
it still has to deal with with image issues. There's
still still, as we'll discuss in the next episode, encounter
people spreading untruths about the microwave, slandering the microwave, and
(38:46):
at the same time, like the microwave is everywhere. The
microwave is one. The microwave is nearly ubiquitous. I guess
it doesn't really need our help, right, um, I mean
the microwave is is waiting for you in your local
gas station, ready for you to to heat up some
sort of prepackaged nonsense that you just purchased. Well, let's
(39:06):
come back next time and heat up that nonsense in
the meantime. If you want to check out other episodes
of Invention, head on over ton invention pod dot com.
You'll also find the show wherever you get your podcasts.
If you want to support this show and uh see
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(39:28):
as always to our excellent audio producer Seth Nicholas Johnson.
If you would like to give us feedback on this
episode or any other, to say hi or suggest topic
for the future, you can email us at contact at
invention pod dot com. Invention is production of I Heart Radio.
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