Episode Transcript
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Speaker 1 (00:04):
Welcome to Tech Stuff, a production from I Heart Radio.
Hey there, and welcome to tech Stuff. I'm your host,
Jonathan Strickland. I'm an executive producer with I Heart Radio,
and I love all things tech. And just the other
day I did a long episode about the history of
(00:24):
lawns and lawn mowers, and I got to dive into
some medieval history along the way to set up, you know,
why we even have lawns in the first place. And
today I thought I would do something similar and that
I thought we would explore the technology around coffee. And
you might be thinking, hey, Jonathan, it sounds like you're
(00:44):
just making episodes out of stuff that you can see
from your chair right there in your home office. And
to you, I reply, s, don't you worry a little
hit about that. It's none of your concern, So let's
talk about coffee now. I also know that episodes like
this one and My Lawnmower one are going into a
(01:05):
lot of history and culture type stuff, not strictly the technology.
But I always feel like an understanding of technology, a
real understanding of it, requires that, you know, we also
explore the greater context, Like we could just talk about
how the technology works at all and how someone came
up with an idea and maybe someone else improved on
(01:27):
that idea. But I think that has limited value unless
you explore why were people thinking about this in the
first place, and what the world was like before and
then after that technology. Also, I've recorded more than episodes
of tech stuff, so changing things up keeps it fresh
from me, and then I don't burn out. But hey,
(01:49):
you folks are my listeners. If you like how these
episodes play out with a deeper dive into the context
around tech, let me know. Now. If you hate them,
you can also let me know, but do it nicely,
because yeah, it's just me doing all the researching and
writing and recording of these shows. Now. Coffee is one
of those subjects that I find particularly fascinating because there
(02:12):
are countless people obsessed with it, and yet details about
its origin and evolution in society are somewhat muddled. It's
amazing that we've got this huge industry around coffee, but
we don't have a lot of historical records to refer
to when it comes time to documenting everything about it.
(02:34):
Maybe people were just too jittery to write anything down,
So in the absence of facts, people will fill up
the gap with speculation. That's just a general rule of thumb.
You didn't think this was gonna be an episode about
critical thinking, but bam, right out of the gate, I'm
hitting you with it. Now, if you google history of
coffee or origins of coffee, you're gonna find results, like
(02:57):
a lot of them. I mean like million of them.
I know because I did it. And if you spend
enough time skimming through a few of these different results,
you're probably going to find several very different explanations about
the history of coffee. Some might start as early as
the sixth century of the Common Era, others might flip
(03:19):
ahead of millennia or so. So this tells us that
we should probably not put too much stock into any
one narrative about coffee. It maybe that none of these
accounts are correct, or maybe they all are, in some
way or another at least partly correct. So we shall
proceed with caution. First, let's talk about coffee the plant
(03:43):
to understand what it is. Now, maybe you've never seen
one in person. By the way, if you ever find
yourself on the Big Island of Hawaii, you can go
to the Kona region and tour one or more coffee plantations.
I've done the tour of Greenwell Farms and it was
super nifty, And no, I don't have any connection to
that farm or that brand of coffee. I just liked
(04:05):
the people that I talked to there, and I found
the tour really fascinating, and the various animals roaming around
the farm were super cool as well. Coffee plants don't
get particularly huge. They typically fall somewhere in the range
from shrub to medium sized tree. Cultivators typically trim the
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branches back to keep them manageable, especially if you're cultivating
them in rows. You want those rows to be nice
and neat, and it allows you to fit more plants
per area of land. They have glossy green leaves and
these plants sprout small white flowers in the springtime, followed
by berries or the coffee cherry. And these are about
(04:48):
half an inch in length or about one point three centimeters,
And these are the coffee cherries. Inside each cherry are
two green seeds. These are the actual coffee beans, which
aren't really beans at all. Their seeds. Inside each cherry
are two green seeds, and these are the coffee beans,
and they're not really beans at all. They are seeds
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and they only become brown after you roast them, and
that comes much, much, much later. The fruit of the
coffee cherry is sweet. You can actually chomp on these
if you want, but there's not a lot of pulp
to these fruits. A coffee cherry is mostly skin and
the two seeds, and then you've got a little bit
(05:32):
of fruity pulp called mucilage on the exterior of the seeds.
The seeds are super hard, so you don't really chew
on the seeds. It would really hurt your teeth. And
it takes a lot of work to eat the tiny
amount of fruit that's on a coffee cherries, more work
than what it's worth, which is why you don't go
to the grocery store and load up on coffee cherries
(05:54):
as a sort of pick me up fruit snack. But
what's the history of humans cultivating coffee for its caffeinated kick.
That was a lot of alliteration that I did not
initially intend. Well, there's one tale that is pretty widespread
to the point that I think we can really consider
it folklore. Now this doesn't necessarily mean it's not true.
(06:16):
It just means that, you know, it's a story that's
been widely passed on through oral tradition, giving lots of
opportunities for that story to change in little ways. I
think it's probably a little fanciful, but again I don't
know for sure. But the story goes that there was
a shepherd in Ethiopia who was tending to a trip
of goats. And yes, I did just google what to
(06:38):
call a group of goats a trip? I guess. I
guess the word heard would have been fine, but I
wanted to get, you know, more specific. And besides, a
trip of goats seems fitting, as this shepherd's goats were
nibbling on some little shrub plants and then they were
tripping all over the place. Man, those goats were tripping,
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or rather they were jumping, skipping and leaping, one might
almost say dancing. And the shepherd, someone who clearly had
a lot of time on their hands, decided, what the heck,
I'm going to see what this is about. And so
the shepherd then took some of the berries growing on
these plants and showed on them, and then felt a
surge of energy. So if you ever wondered whose job
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it was to test the various types of fruits and
mushrooms and everything else to make sure that it was
safe to eat. I'm guessing was folks like our shepherd
in this story. Here. Also funny side note, the coffee
shop I go to all the time has a name
that references this folk tale. The coffee shop is called
Dancing Goats. Now when this story happened, if it happened
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at all, is also a matter of debate, but generally
we're looking at around mid ninth century of the Common Era,
or around eight d fifty a d if you prefer.
But as I say, there's not really any evidence that
it definitively happened. And heck, I'm not sure anyone would
even think to record that kind of event. I mean,
(08:08):
dear Diary, I saw my goats eat some berries and
then they went totally bonkers. So I ate some berries,
and I too went bonkers. Tomorrow I opened a Starbucks.
Like that just didn't happen. So there are some facts
that at least make the story or some variant of
it possibly true, And the big one is that the
(08:28):
coffee plant grows naturally in Ethiopia in a region called Kafa,
So did coffee get its name from kafa, or did
kafa get its name from coffee? Heck, if I know,
there are other words that sound a lot like coffee
that are directly associated with coffee. So this is one
of those that I think I will leave to the
(08:50):
linguistic experts. Now. It's possible that some people had discovered
the properties of this odd little fruit long before the
ninth century. But the first written account about coffee that
I could find evidence of came from a philosopher named
Rozis from Persia who lived right around the time that
the Shepherd's story might have happened. Rozis wrote of a
(09:14):
medicine used by the peoples of Ethiopia. It was a
drink made from the fruit of the coffee plant, but
from the description it didn't sound like coffee as in
the drink that we enjoy these days. Yemen is a
possible origin point for coffee, the drink as we know it.
Sufi monks and Yemen brought coffee cherries from Ethiopia, and
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then they cultivated the plants, and Yemen it grew just fine.
And Yemen as well. The monks made a sort of
tea from the coffee plants. Leaves to help them stay
awake longer and get more prey and done. Now, this
would have been around the fourteen hundreds, and it's possible
that these monks gradually developed the process of roasting and
grinding coffee beans to make their stay awake juice. In
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the fifteen hundreds, the Turks came a colon. The Ottoman
Empire was an expansion mode, and while it never extended
all the way down to Ethiopia, it did get quite
the foothold in the Arabian Peninsula, which is where the
Turks first encountered coffee, and they really liked it like
a lot, and they called it covey, which in Turkish
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meant the wine of Arabia. The drink made from roasted
coffee beans soon found its way throughout the Ottoman Empire,
which was enormous and spanned parts of Europe and North
Africa at this point, and growing coffee outside of places
like Yemen and Ethiopia proved to be challenging. In part,
that was because the plants thrived in very warm, like
(10:50):
tropical style climates and temperate Europe was just a bad match.
It was too cold. But the merchants selling coffee also
saw a threat to their trade if people were able
to grow the coffee plants in any old place, and
so they would frequently boil or otherwise alter the beans
before selling them, so that those beans would be infertile.
(11:11):
If you were to plant them, nothing would grow from them,
and then they would ship those off to be sold
in places like Europe. It wouldn't be until the seventeen
hundreds before someone, that being the Dutch, was able to
get hold of viable coffee beans and find a place
to grow them outside of the general areas of Yemen
in Ethiopia. But we'll get back to that. By the
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mid sixteenth century, coffee shops were opening up in Constantinople.
Now you can't go back to Constantinople, so if you
have a dating Constantinople, she'll be waiting in his stan bull.
I have no idea if it was common for a
coffee house to open up right across the street from
another coffee house, or if that's just something we do
here now. Over in Western Europe, it said that some
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high ranking Catholic priests resisted the spread of coffee, declaring
it to be a devil's brew. I mean it kept
you awake, It gave you energy. It clearly was unnatural.
But the Pope apparently like the stuff and said, Noah,
this is fine. It's fine. And so coffee spread throughout
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the Christian world as well over in England, where they
had already had a little tiff with the Catholic Church,
it was now the Anglican Church in control. Over in England,
they got their first coffee shop by sixteen fifty. That
was just a century after the earliest ones we know about,
opening up in Constantinople, which really surprised me because frequently,
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when it comes to trends in the Middle Ages and Renaissance,
England typically is a latecomer because it was, you know, separate.
It was not part of the mainland of Europe. Still
isn't as far as I know. I haven't looked at
a map recently. But in this case, the Brits got
their coffee before the French started opening up their own
coffee shops. Coffee even made its way over to the
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colonies in North America, with a coffee shop opening up
in what would become the city of Boston in sixteen
seventy six. Okay, so the Dutch I mentioned that they
got some viable coffee beans essentially smuggled them out of Arabia,
but they had to find a good place to grow coffee,
and that turned out to be Indonesia, specifically the colony
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of Java, which is why we sometimes referred to coffee
as Java. The Dutch secured their coffee beans through trade
with a port city in Yemen, and that port city's
name was Mocha. That's how we got Mocha Java. Starting
in the early eighteenth century, from their colonialism, would spread
coffee to other parts of the world, such as Sumatra
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that's an Indonesian island west of Java, Central America, South America,
the Caribbean, and Hawaii. And before you can throw some
coffee scenes or beans into a grinder and prep your
morning cup of joe, there are a lot of stuffs
that have to take place between growing it and brewing it. First,
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someone's got to harvest those cherries from the coffee plants.
And in fact, there is a whole element to this
story that I'm not going to dive into, but it
does involve some pretty terrible conditions for workers in various
parts of the world. There's a lot of exploitation going
on whenever you're talking about mass farming in places like
(14:22):
Central America or South America, or Indonesia or Africa, you've
got a lot of opportunities for companies to do things
that are not necessarily the best for the employees. But
that's a matter for another episode. On smaller farms, harvesting
might be done by hand, possibly with some hand tools,
but on the big farms, heavy machinery is frequently used.
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While some coffee farms use pickers to harvest cherries by hand,
like just with their hands alone, others rely on some
of those simple hand tools. I was talking about one
tool I've seen for harvesting coffee really surprised me. I
hadn't really seen anything like it before. Or kind of
looks like a pair of tongs, and that there are
two rods that extend out from a plastic handle, and
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the handle actually has motors in it that vibrate and
rotate those fiberglass rods. So while you're operating this harvesting device,
those rods are spinning and vibrating very quickly. To harvest
the coffee cherries, first, you put a tarp down to
catch all the cherries that are going to fall, which
is pretty much the same thing you would be doing
if you were harvesting everything just using your hands alone.
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Then you would position the rods on either side of
a branch that happens step berries on it. You'd squeeze
the handle so that the two rods come together and
and touch the branch on either side, thus transmitting vibrations
to the branch, and then you move the tongs down
along the length of the branch to shake the berries free.
It's still a lot of work because you have to
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move from branch to branch, but it's more efficient than
doing it all with just your fingers. Now, this is
a fairly simple device with electric motors in the handle
that draw power from a battery pack, so I'm not
going to go into deep detail. There's not a whole
lot of of advanced tech there. It's just the idea
of creative vibrating motor that transmits vibrations to a rod.
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Those rods transmit the vibrations to a branch you knock
the cherries loose. Another tool I've seen for this kind
of harvesting looks almost like a weed whacker or a
weed eater, except instead of having a rotating blade or
a rotating wire. At the end of the device, you
actually have what looks like almost like a fiberglass rake
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um or a fork. In fact, it does look like
an enormous gas powered fork, and the motor when you
turn it on, makes the tines of that fork vibrate.
So again, you would just use this device to grip
several branches of a coffee planet. Once you give some
gas to the motor, it causes the times to shake,
(16:54):
and it shakes the cherries free from the coffee plant,
and presumably you catch those on a tarp. But for
really big farms, there are some massive machines that farmers
used to harvest coffee. When we come back, i'll explain more,
but first let's take a quick coffee break, all right.
(17:20):
So for smaller coffee farms, or maybe ones that are
on like really uneven terrain, you might not be able
to use big machines. They might just not be able
to maneuver through those. But for coffee plantations that are
really huge, particularly ones that have coffee plants and neat
rows and fairly level ground, you get a lot of options.
One harvester I've seen is a big device that's actually
(17:43):
stationary when it's an operation, and it looks kind of
like a big metal wagon with an archimedean screw inside
of it and a shoot like protrusion at one end,
which is where the coffee cherries will come shooting out
and into another container. So you would tow this big
thing to the end of like a pair of rows
of coffee plants that stretch pretty far back, and between
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the rows you lay down a tarp. This tarp will
become a sort of conveyor belt for the harvester, and
workers would go down the rows of coffee plants and
use pruning shears to trim back branches that have berries
on them. All of these branches with berries on them
fall down to the tarp below, and once that's done,
you feed the tarp into essentially a roller in the harvester,
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which will start to pull the tarp into the machine.
Uh And they typically also has some sort of hinged
metal frame that you can use a sort of a ramp,
so that way the tarp is going up at a
at a gentler angle. It's not going up so steep
that everything falls off the tarp. So the machine starts
pulling the tarp toward it and everything on the tarp
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gets pulled along with it and dumped into a chamber.
And in that chamber there is that Archimedean screw at
the bottom. And if you don't know what that is,
is a cylindrical drum with a helical blade. It's the
type of thing that Archimedes used to draw water from
areas of low elevation to high elevation, and in this case,
it's used to transport the coffee cherries up toward another
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set of devices attached to this machine. So the branches
and berries and leaves and all go into this chamber
with the turning our comedian screw. The rotational motion separates
the cherries from the branches, and the cherries effectively roll
up the screw because of that rotation. This is a
little hard to explain an audio, so I recommend you
check out the videos of watching an archimedian screw in action.
(19:38):
You'll see how it all works. And the cherries and
maybe some bits of leaves and twigs hit a shaking
grid at the top of that archimedian screw. This shaking
grid acts like a filter. It allows the cherries to
pass through the filter. Everything else doesn't or at least
most of everything else doesn't. And then the cherries ride
a second conveyor belt that has you know, these little
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ridges to keep the cherries from rolling back down, And
this belt carries the cherries up a shoot and then
they come out the other end and fall into whatever
containment vessel you have to collect all those coffee cherries. Uh,
you could end up with something that looks like essentially
a dumpster full of coffee cherries, and the branches and
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leaves they get left behind are are chopped out quite
a bit. They eventually exit the machine through an exhaust,
kind of like the way a lawnmower has one of
those little side exhaust ports where cut grass flies out. Now,
this sort of device can harvest a lot of cherries,
but it does require a ton of manual pruning work
at the top end of it. There are some other
(20:41):
harvesters that take the cherries right off the plants without
needing to cut the branches onto a tarp first, and
they look pretty funky. Now, there are a lot of
variations on this next type of harvester, but they do
share a few things in common. And the easiest way
I can think of to describe this is imagine a
(21:01):
mechanical automated car wash. You know, you drive your car
into the bay of this car wash, and then once
the car washes operating, these big machines will rotate giant
brushes that come up against your car and scrub all
that road grime off your vehicle and then you drive out. Well,
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imagine that you've got a car wash, but the car
wash itself is on wheels, So instead of the cars
driving into a stationary bay, you could have a line
of cars that are you know, bumper to bumper in
a line, and you have this wheeled car wash go
down the line of parked cars, and the car wash
is the thing that moves. Well, that's kind of what
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these harvester things are. Acceptance to have a car wash. Obviously,
they are harvesting coffee cherries off of plants. So you've
got this big machine that has a space where a
tree can pass through the middle of this machine. The
machine is on wheels, so it can move because you know,
these are coffee plants. They're not ents from Middle Earth,
so they don't walk around on their own no matter
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how much caffeine is in them. Some of these machines
are things that you have to tow behind a tractor,
But some of them have a tractor like system built
into the actual machine. So some of them have their
own engine and motor that allows you to drive the harvester,
whereas others are a separate piece of machinery that hooks
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onto the back of a tractor. I've seen both versions,
but either way, a driver manipulates this machine, so it
moves down a line of coffee plants in order to
harvest the cherries. So how is that harvesting actually working well?
On the inside where the trees are passing through, You've
got poles with fiberglass rods on either side of where
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the coffee plants passed through. So it kind of looks
like one of those round brushes where you've got the
bristles on all sides of the round brush. It looks
like a pair of those, except not quite as thick,
and you've got a bunch of fiberglass rods instead of bristles,
and instead of big rotating brushes from a car wash,
you've got these things and they do rotate, and the
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fiberglass rods vibrate as they're rotating, and it's this motion
that shakes loose the coffee cherries as the plants pass
through the middle of the machine. At the bottom of
this are some hinged panels that can allow a tree
trunk to pass through in one direction, but the panels
locked from being able to go in the opposite direction.
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So they're hinged in a way where uh they swing
open to allow a tree trunk to pass through, but
when they close, they can't go back the other way.
So once you head down a row of coffee plants,
you're kind of committed. The hinged panels catch stuff that's
falling down from the coffee plants that gets shaken loose,
and all that material, including cherries, toigs, leaves, bugs, moves
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towards a pair of conveyor belt, one on either side
of the inner part of the machine. These conveyor belts
move everything up to either a containment chamber or out
of to a shoot where they get put into a
separate trailer that's being hauled behind a different tractor, perhaps
one row over. I've seen both um, but some of
(24:20):
these things are kind of an all in one machine
where they can do all the driving, the harvesting and
collecting of coffee cherries by themselves. And don't need any
additional equipment or other people operating that equipment. Some of
them are used in concert with other heavy duty machinery.
There are a lot of videos online if you want
to see these coffee harvesters in action. It might be
(24:42):
a lot more helpful rather than trying to imagine my
poorly constructed word picture. Uh. The the machines are pretty impressive,
and they're actually based off older harvesters that have been
used for stuff like blueberry farms. Now, before I did
this podcast, I had never seen anything like this. Being
the city boy I am, and also I mean I
have actually done some very very minor work on a farm.
(25:07):
Uh it's barely worth mentioning. But it was a much
smaller operation, not something that would have this big equipment.
So I've never seen anything like this. It was really
cool to learn about it. One of the videos I
watched for this episode had a coffee farmer named James
Chemo Falconer, and he talked about the efficiency of these
types of harvesting machines. Now, according to Falconer, a skilled
(25:29):
coffee picker would be able to harvest around two hundred
pounds of coffee cherries in a day. One of these
harvesters could actually harvest forty thousand pounds of cherries in
around six hours, so it is phenomenally efficient compared to
manual labor. Now keep in mind we are still talking
(25:50):
about coffee cherries here Again. According to Falconer, there's about
a five to one ratio in weight of cherries to
weight of green coffee beans for natural coffee. Some varieties
of coffee might have cherries with slightly more or less pulp.
That would change the ratio a bit. But if you
(26:10):
harvest forty thousand pounds of coffee cherries, that doesn't mean
you've got forty pounds of coffee beans. It's like a
fifth of that. Now, the harvested cherries have to be
washed to remove dirt, stems and that kind of stuff.
There's typically an early sorting process to help separate out
unsuitable coffee cherries from the good stuff. One way that
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you can do that is dumping all the cherries into
giant vats of water. Cherries that float to the top
aren't ripe. They can be skimmed off and they can
be removed and then punished. I'm kidding, they're not punished,
but they are turned into fertilizer, typically so that you
can use those to help fertilize the ground for future
coffee plants. Now, what happens next is dependent upon the
(26:54):
post harvest process for that particular coffee farm or plantation.
Dry regions might use natural processed coffee, which involves leaving
the seeds inside the coffee cherry and allowing the whole
thing to dry out, which takes about four weeks and
it requires lots of supervision to make sure that mold
doesn't form on those coffee cherries. And after drying, workers
(27:18):
put cherries into a huling machine. Uh. There are a
lot of different versions of this. One of them is
just essentially a big vibrating tray. You put the coffee
cherries into this vibrating tray. It often has a rough bottom,
and the vigorous shaking of that tray using an electric
motor to to shake this thing ends up rubbing and
(27:38):
shaking the cherry so that the dried skin and dried fruit,
and the parchment on the seeds itself all gets rubbed off,
which really means that those those seeds, those coffee beans. Now,
the green coffee beans just need to be polished before
they're sent off to roasters because you've already done all
the work of removing everything else that's around the bean.
(28:02):
But another climates, different post harvesting methods work better. So
you've got stuff like your honey processed coffee or your
wet hull process, which is mostly used in Indonesia, and
you've got your washed coffee processing. Now there are several
things that differentiate these processes, and even plantations that use
(28:23):
the same general process will have their own way of
executing that process. So there's no I can't give you
a universal here's how it works. I can give you
some generalities with each. So with honey processing, the cherries
are skinned right away after harvest, but the sticky coating
on the seeds that mucilage. That mucilage is allowed to
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stay on the seeds while they go to areas to
be dried out. The washed process involves pulping the seeds
not long after harvest. You allow the seeds to ferment
a bit like overnight, and then you wash the musilage
off before you allow the coffee to dry, and that
coffee will dry faster because it doesn't have that insulation
(29:10):
around it. But that also means that it's not in
contact with the fruit for as long, and that will
change the flavor profile. In the case of natural processing,
honey processing, and washed processing, the goal is to get
the moisture level of the seeds down to around eleven
before you move on to hulling the seeds, to get
that thin layer of parchment off the coffee seeds before
(29:34):
you can send them off to roasters. Now, the wet
hull process of Indonesia is a little bit different because
of the high humidity levels in Indonesia, it would be
really hard to dry seeds down to eleven water content
on their own, even with the washed process method, So
instead they pulp the cherries so that you get the
(29:57):
seeds the coffee beans, and then they dry those coffee
beans until the water content is around thirty percent or
so remember the other ones are, and then they feed
those to a hauling machine to remove the parchment layer
around those seeds at that point, whereupon they dry more efficiently.
In the human climate, the other processes I mentioned leave
(30:18):
the parchment on the seeds until after the drying process
is done. The parchment helps protect the seeds against stuff
like disease and mold, but in the really humid climates,
Even that thin layer of parchment slows down the drying process,
so in order to get the seeds dried and to
market while they're still good, they have to remove the parchment.
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In places like Indonesia, pulping and hauling machines can be
vibrating trays like the one I mentioned for natural processing,
or they can involve feeding the cherries or seeds. In
the case of if you're just removing the parchment into
a feeding hopper, and at the bottom of the feeding
hopper is typically a rotating drum that's got little nubby
(31:00):
protrusions on it, and as the drum rotates, this agitation
UH squeezes seeds out of the cherries, and it can
also remove parchment from the seeds if you've calibrated the
machine to do so. But it's that rotational force that
is UH kind of separating the cherries out from the
seeds infect It kind of squeezes them out and the
(31:21):
chair the seeds go one way, and the cherries, the
pulp and the skin go the other way. So you
will get one shoot where green coffee beans will slide down,
and then on the back you'll just have this mass
of pulp shot out the back of the the machine,
which again is used often for fertilizer. The holed coffee
(31:42):
then has to be sorted by size, and a typical
sizing machine has a series of meshed trays stacked one
on top of the other in a vibrating device, and
the holes in the mesh decrease in size as you
go down the stack vertically, so larger seeds will be
caught by one of the upper trays because the seeds
will be too large to pass any further down in
(32:04):
the link of of meshes. Uh, the smaller seeds will
eventually collect in the bottom trays because they'll pass through
the larger holes on the upper ones. Then the coffee
can be graded based on coffee bean size. The best
coffee beans, by the way, are not necessarily the biggest ones,
nor are they the smallest. It's typically the just right
(32:24):
the goldilocks zone. Those seeds also have to be examined
to make sure they are the right quality. They have
to be looked at to make sure they're the good color.
This can be done by I but when you're looking
at really big operations, that's not practical. So we've got
some high tech to do this too. There are advanced
machines that use l e ed s and high resolution
(32:44):
cameras and imaging software to examine seed color and consistency,
and that makes it possible to sort large quantities of
seeds and remove any that don't meet specifications. So I
always think of the Willy Wonka and the Chocolate factory
scene with the golden eggs. You've got these machines that
are looking at seed by seed very very very fast,
(33:05):
and if the color and the consistency matches the specifications
that the machines software has set to, then the beans
are allowed to continue on their path. If not, they
get the boot. They are the proverbial bad eggs in
this case. Other machines sort the beans by density using
vibration and air. So, in other words, you've got a
(33:26):
big stack of beans, you put them in this machine.
The machine shakes the beans, that uses some air to
blow against the beans. The heavier beans will be closer
to the bottom of this machine. They'll be heavy enough
and dense enough to make their way to the bottom.
The very light beans will be more towards the top
of the machine because they'll be blown by the air
(33:46):
and they will be pushed up from all the heavier beans. Now,
you want to do this because sometimes those lighter beans
are actually representative of beans that have been you know,
munched on by insects and stuff. Those are not the best.
So it's another way of sorting beans out very quickly
for quality control. Now, what I think is really cool
about a lot of these devices is apart from the
(34:09):
one that tends to use like high resolution cameras to
look at bean color. Now, what I like about a
lot of these devices is that a lot of them
use a pretty simple mechanical approach to help sort out
all these beans. I just think it's a neat and
pretty elegant way of doing things. All this takes place
(34:29):
before roasting. The coffee roasters take incoming green coffee beans and,
depending on the flavor qualities of the bean, which in
turn are determined by stuff like where in the world
it was grown, what sort of post harvest processing to
go through that kind of thing, the roasters then take that,
they take that flavor and they determine what sort of
(34:50):
roast they should follow for those particular beans. The beans
are put into roasting machines, which look a lot like
clothes dryers. A lot of these, especially for the larger roasters,
are gas power. They actually use natural gas for a
heating element. So a typical roaster has a hopper feeder
at the top that's where you pour the green coffee
(35:10):
beans in. These flow into a barrel that is inside
the roaster. The barrel can rotate, and the barrel has
burners on the outside of it, so inside the machine,
but outside the container of the barrel are these burners.
They heat up the air and the barrel itself, and
(35:31):
that allows these beans to get a lot of heat
directed at them in a very short amount of time.
And you use a combination of temperature and time in
order to roast the coffee beans. They're constantly being circulated
so that each bean is getting evenly heated. And typically
there's a way to remove beans from the middle of
(35:52):
this process while it's still going, so you can check
on progress. Uh. There's frequently something that's called like a
sample spoon. This is a little container that actually can
extend into the barrel as it's an operation, but there's
a handle on the outside of the machine that you
can grab. You can pull the sample spoon out, check
the beans that are in the process of roasting and
(36:15):
reinsert the sample spoon to put them back into the barrel,
and you know, use that to check to make sure
that you're not going too far with your roasting process.
After roasting, the roasters will essentially open a flap to
the barrel to let the roasted beans pour out of
the barrel into a cooling tray. Then the roasters will
either stir the beans or typically a lot of these
(36:37):
cooling trays have a mechanical stir that will just do
rotations through the beans and mix them up. That allows
the beans to cool and stop the roasting process from
going on much longer after they've already emerged from the roaster. Now,
the length of time spending those chambers, along with what
temperature you set it to, that determines the level of
(36:58):
the roast, and the flavors can change in that time
as well. So a light roast coffee uses beans that
have been in a roaster for much less time than
a dark roast coffee, and light roasts tend to be
a little more floral. Dark roasts tend to have more
chocolate e or caramel flavors, but also roasting the longer
(37:20):
eu roast. The more you typically reduce the amount of
caffeine that's in the the coffee bean, the caffeine gets
kind of roasted out gradually. There's still some there, but
less so. While an espresso has a very strong flavor,
it can actually have much less caffeine per volume than
a simple light roast coffee. Though this is also dependent
(37:40):
upon the type of bean that was used at the
very beginning of the process, so it gets a little
more complicated than that. There are some great videos on
YouTube of master coffee roasters describing the process they use,
which frequently needs to have some flexibility built into them.
Figuring out the perfect temperature and the perfect timing to
get the kind of roast you want is kind of
a matter of science and art. It's fascinating stuff. Now,
(38:04):
when we come back, I'll talk about the evolution of
the coffee maker. One thing I did not cover in
the previous section is how companies make decaffeinated coffee and
coffee beans half caffeine in them. How do you decaffeinated Well,
(38:24):
there's a couple of different methods, but generally the process
involves leaching the caffeine out of the green coffee beans.
Using some form of chemicals or an activated charcoal filter
to bind with the caffeine, and then continuing to soak
green coffee beans so that some of that delicious flavored
juice goes back into the bean. In fact, in many
(38:47):
of these processes, the first batch of green coffee beans
is either a loss. You just throw them out after
you've soaked them in hot water, or you have to
set them aside because it's not just the caffeine that
leeches out. There's also a lot of those oils that
make up the aromatics and flavor of the coffee bean.
So if you wanted to decaffeine eate a batch of coffee,
(39:09):
you would put your first group of green coffee beans
in a vat of hot water, and then the water
becomes saturated with caffeine and these oils. Then you would
use chemicals or a charcoal filter to bind with that
caffeine and remove the caffeine from the mixture, and then
you could remove the green beans from that mixture, and
(39:33):
then you add more green coffee beans, the ones that
haven't been processed yet into the vat. Now the hot
water is already saturated with the oils from the first
batch of coffee beans. So the second batch of green
coffee beans keeps the flavors and aromatics for the most part,
but the caffeine still leaches out. Then you use that
same chemical process to bind with the caffeine molecules and
(39:54):
remove the caffeine from the mixture. And at the very
end of this process, after you've done batch after batch
after batch of the green coffee beans, maybe then you
go ahead and you add back that first batch of
coffee beans to stew in the juices. As it were,
These are the coffee beans that were sapped of not
just their caffeine but all their coffee goodness, and you
(40:15):
let them sort of reabsorb those chemicals minus the caffeine. Obviously,
now it's a little more complicated than that, and as
I mentioned, there are a few different approaches to this,
but I still need to talk about coffee machines, so
let's move on. Gosh darn it. So to brew coffee,
you grind up the beans to create more surface area
(40:35):
for the beans to make contact with hot water. That
allows more oils to transfer to that hot water, and
thus the drink we call coffee is made. And there
are many different sizes of grinds of coffee, ranging from
course to extra fine, and they're they're good for different
types of coffee preparations. For example, a very coarse grind
(40:56):
is recommended for cold brew coffee or French press coffee,
a meat grind is good for your standard automatic drip
coffee machines, and an extra fine grind is really good
for Turkish coffee pots. Typically, you want to filter out
the coffee grounds from the water so that the stuff
you've brewed doesn't have coffee grounds in it, unless you're
(41:17):
making Turkish coffee. So you might pour boiling hot water
over coffee grounds that are in some sort of filter.
That's the classic pour over coffee, or, as is the
case with most coffee machines, you have a filter or
perforated surface that keeps the grounds from passing through and
the coffee can move on into a caraft or pot
(41:40):
or pitcher, while the coffee drink is able to you know,
flow freely and everything. One of the earliest modern applications
for coffee making is the humble percolator. Joseph Henrie Marie Lawrence,
a metal worker in Paris, invented such a device in
eighteen nineteen. The ideas atty simple. You've got a pot
(42:02):
complete with a spout. You know, it doesn't look that
different from a kettle. UM. This sits on top of
a source of heat, like an open flame or an
electric stovetop. You fill the bottom part of this pot
with water. You've got a vertical tube that extends up
from the bottom of the pot to the top. Sometimes
this is actually a separate piece that you insert into
the pot after you've already filled it with water. UM.
(42:24):
That means that the water in the tube is at
the same level as the water level of the pot.
And at the top end of this tube is a
perforated basket of some sort. That's where you put the
dry coffee grounds, and the water is in that chamber underneath.
As the water boils when you put it on this
heat source, some of the bubbles forming begin to push
(42:46):
water up that tube. So the hot water travels all
the way up the tube out the other end, and
it typically hits like a spreader plate or a drip
plate of some sort that distributes this hot water, so
it drips down onto the coffee grounds. UH. This hot
water then seeps up the oils and caffeine as it
(43:06):
does this and drips down through the perforations back into
the water chamber below, and the whole process continues. Uh Percolation,
by the way, refers to filtering a liquid through some
sort of porous material, and that actually means that most
but not all coffee makers are actually percolators. But never
mind that in America we just call the little bubbling
(43:29):
stuff we see percolation. That's not really true, it's not accurate,
but it's what we call it. So the boiling water
brewis the coffee, and eventually all that boiling water in
the bottom of the pot is really brewed coffee as
this process continues in the coffee recirculation also means that
you typically end up with a pretty darn strong cup
(43:49):
of coffee at the end, and that's because the coffee
and the fresh water mixed together and the concentration of
coffee increases the longer that the percolator is percle eating.
The stovetop or open flame versions also have a drawback.
They typically are pretty bad about burning coffee as well,
so it's a good efficient way to make a potentially
(44:13):
terrible cup of coffee. Much later. Other inventors came up
with electric percolators, some of which designated a very small
area of the bottom of the pot as a heat source,
so that the area directly under where the tube is
would become hot enough to cause bubbles to push water
up the tube, just like in the stovetop version, but
the rest of the water in the pot wouldn't be
(44:36):
directly on a heat source, so cold water from the
most of the pot would end up circulating in to
replace the hot water that's going up the tube, and
you wouldn't be as likely to burn your coffee. However,
like other percolators, this is another method where the fresh
water and coffee mixed together and the coffee recirculates to
(44:58):
the system, so you still get a pretty strong cup
of coffee. Not necessarily a good one, but a very
strong one. In the nineties seventies, Samuel Glazer and Vincent
Moroda got an idea. They thought of a way to
create an automatic drip coffee maker, which was a kind
of a way to create a pour over coffee without
actually having to manually pour water over coffee grounds sitting
(45:21):
in a filter over a craft. With the original Mr Coffee,
you would put a filter in the coffee grounds basket.
You would fill that filter with coffee grounds, and then
you would fill a chamber at the top of the
machine with water, and you would put your coffee craft
under the filter spout and you would turn on your
coffee maker, and gravity did most of the work. Really.
(45:42):
It would pull the water downward through this coffee maker.
The water would pass over heating elements that raised the
temperature of the water dramatically before that water would then
drip down over the coffee grounds in the filter, and
then the water would go through the filter, carrying those
oils nearromatics and caffeine into the graft. Later versions of
the coffee maker changed up this design. They used a
(46:04):
water reservoir that requires thermodynamics to move water up a
tube to pass it over the coffee grounds, but it
no longer used a gravity fed system. So a typical
coffee maker would have a little hole in the bottom
of the water reservoir that you fill up with cold water.
So cold water goes from the reservoir down this hole
(46:24):
into an aluminum tube and it passes through a valve
that allows water to travel only in that direction. It
can't go backward, So in the aluminum tube, the cold
water passes near heating elements. These are coils of wire
that heat up when you pass electricity through them because
of electrical resistance, and that transfers heat to that cold water.
(46:45):
The heated water inside the aluminium tube begins to boil,
so bubbles are forming, and because you have that valve
that is blocking the bubbles from going back up to
the reservoir, they can only travel forward up the tube,
pushing water up as it goes up, and this hot
water comes out of the top of the tube and
then filters out to hit the coffee grounds, which then
(47:08):
percolates right same same sort of thing as the percolator,
except in this case you've got the supply of fresh
water separate from your finished coffee, because the hot water
comes up, hits those coffee grounds, filters down through, carrying
those oils and caffeine and everything, and then drips into
the empty caraft underneath the filter, so you don't have
(47:31):
to worry about the coffee mixing with fresh water and
then recirculating through the system. And this was said to
create a much more consistent cup of coffee, so you
didn't end up with this burnt coffee taste or super
strong taste. Glazer and Moroda did call their device Mr Coffee.
It represented a huge change in how Americans would make
(47:52):
their breakfast beverage, and it was one of those inventions
that made coffee far more convenient and cut back on
the problems of burnt coffee in general. Though, the heating
plate on most drip coffee makers can also burn coffee
if you leave it turned on with the craft on
top of it. So after you finished brewing coffee with
an automatic drip coffee maker, I recommend you turn off
(48:14):
the coffee maker. I know that means that the heating
plate is going to be off and that the coffee
will gradually go cold. But one only brew as much
coffee as you actually need, and to drink it not
long after you brew it, because that's when it's best.
Otherwise you're just you're just making things worse for yourself, honestly. Now,
there's a lot more we could talk about. Right There
(48:36):
are the curig machines and their pods and the danger
that that presents to the environment if you don't have
compostable pods. There are French press machines which actually use infusion,
not percolation for coffee. There are espresso machines which use
pressurized hot water pushed through a coffee puck a puck
(48:59):
of coffee grounds. There are all these other things that
we could talk about, but we're running along, so I'll
do a look at some of the materials see if
there's enough to justify a second episode, and if so,
we'll follow this up with another coffee themed episode of
tech Stuff, and if not, maybe I'll pair it with
something else. Maybe we'll do sort of you know, breakfast tech,
(49:21):
and we'll include some of the coffee stuff I didn't
talk about and some other technologies. In the meantime, If
you guys have suggestions for things I should tackle on
tech Stuff, whether it's a specific technology, a trend in tech,
maybe it's a company that you want me to talk about,
whatever it might be, let me know on Twitter. The
handle to use is tech stuff H s W and
(49:42):
I'll talk to you again really soon. Text Stuff is
an I Heart Radio production. For more podcasts from I
Heart Radio, visit the I Heart Radio app, Apple Podcasts,
or wherever you listen to your favorite shows. Three