You're familiar with the coffee species arabica,
then you're likely familiar with Coffea canephora,
known commonly as robusta.
There are over 120 known species of coffee,
many of them discovered and described
by Dr. Aaron Davis of Kew Gardens.
These wild species are indigenous to countries
across the world,
and in a few cases, cultivated and consumed,
but most are not viable
when it comes to being a global crop species
that we might cultivate to ultimately drink
and enjoy each morning.
There is one species of coffee
that I've always been fascinated by.
It's called Coffea stenophylla.
While many species were never grown and consumed as coffee,
this one was.
Historically, it grew in West Africa,
and can be traced back to 1794 in Sierra Leone.
It was named in 1834
and characterized as having narrow leaves,
which gives the species its name.
Its production was centered in Sierra Leone,
but it was also grown in Guinea, Ghana, Senegal,
Ivory Coast, and even briefly in Uganda.
Although it could grow at low altitudes
and despite reports of having excellent taste properties,
it fell out of favor due to its poor yield,
compared to that of robusta.
From the 1940s onwards, production declined,
and by the 1980s, it had pretty much vanished.
It was one of the descriptions of its taste
that stuck with me from the moment I read it.
William H. Ukers's book, "All About Coffee,"
first published in 1922, is considered by some
to be the seminal and definitive coffee writing of its time.
In it, he briefly describes the species stenophylla.
"Coffea arabica has a formidable rival
in the species stenophylla.
The flavor of this variety is pronounced by some
as surpassing that of arabica."
The line stuck with me
and the desire to taste stenophylla was lodged
into my brain,
though, due to the disappearance of the species,
I quickly came to accept
it would be one I would never achieve.
In 2020, Dr. Aaron Davis was the lead author
of a paper describing the work done
to try and find stenophylla again in the wild.
Aaron had a jar of stenophylla beans on his desk
that had been collected in 1873 and submitted to Kew,
making this something of a passion project for him.
The combination of field work in Sierra Leone
and genetic analysis was used to hunt it down.
What many producers had thought was stenophylla
turned out to be robusta.
But they did manage to find two samples
of stenophylla growing in the wild.
Now, Dr. Davis is publishing a followup paper
written as a collaboration between Kew,
Greenwich University, CIRAD,
and their partners in Sierra Leone.
And this has just been published in Nature.
We traveled down to Kew Gardens to speak with him
about his latest findings
and the potentially huge implications it has
with the coffee industry.
It, it really was a sort of hair standing up
on the back of your neck moment
because immediately it's, it was showing those qualities
that you, that you require in, in high quality coffee.
I've tasted quite a few wild coffees, probably about 20,
and generally they're very disappointing.
When we actually cut it and we tasted it,
the most surprising thing was that tasted like arabica.
And not only did it taste like arabica,
it tasted like a Rwandan arabica,
a bourbon of, of high elevation, like a high-quality coffee.
We're, we're in the Palm House here at Kew,
and you can probably tell it's pretty hot.
It's 30 degrees in here
and that is the sort of environment you would expect
of stenophylla.
Now, that's quite different,
what you'd find in most high-quality arabica-growing areas,
like Ethiopia,
where instead of, of a hot tropical environment like this,
we're looking at a cool tropical environment.
According to latest IPCC report,
it's unlikely we're gonna keep global warming
under two degrees C.
Even if we get another one degree increase,
that is gonna be devastating to the coffee sector.
This was the exciting thing here,
we had a plant that tasted like arabica
but is able to grow and produce a crop
under much warmer conditions.
When we were doing our tasting
at, at Union Hand-Roasted Coffee in East London,
what we didn't realize,
the French research group CIRAD were doing the same
with a sample that they were growing
in Reunion, one of the Mascarene Islands.
As part of the paper,
what we did was to do a climate analysis comparing robusta,
liberica, arabica, and stenophylla,
and what we found was stenophylla were growing
at temperatures six degrees,
or even actually up to 6.8 degrees warmer
than arabica coffee.
What we're focusing on is, is the longterm future
of coffee production.
It's the breeding aspect that's gonna be really important.
So I've been doing coffee research for over 20 years
and made lots of interesting discoveries, but for me,
I think this is the, the discovery
or, or the piece of research that we've done
that's the most exciting
in terms of having an impact longterm.
At the end of our conversation,
Aaron had a little surprise for me.
He gave me a small sample of stenophylla from Sierra Leone
that he had left over.
I took this back to the roastery to have a proper look,
and the first thing we did was to screen out any broken
or defective beans from the sample.
The preparation of this coffee was pretty different
to what we would typically see
for specialty arabica coffees.
So, in this bowl, 12 grams of Coffea stenophylla beans,
ready to be ground, ready to be brewed, ready to be tasted.
Because you'll have watched this video up to this point
and you'll be desperate to know what does this taste like?
My tasting now is not gonna feed
into any of the science going on,
that, that's already been done,
50 and 60 in tasting panels have already tasted this
and declared it to be good, to be interesting,
to be of significance.
I'm just gonna try and talk about what I'm tasting
to try and communicate to you, you know,
using some frame of reference you might have,
exactly how these taste like or unlike arabica,
or like robusta, or like liberica, or anything like that,
I'll try and give you as much context as I can
without losing myself in ridiculous coffee-tasting language.
One interesting thing before I grind the beans
is actually their shape is quite unusual,
they're kind of a teardrop shape,
quite pointed at one ended and rounded at the other.
I'm gonna grind these in a hand grinder
just 'cause I wanna minimize any retention
that an electric grinder might have 'cause grinding them
is gonna be the first moment I really get
to kind of interact with how they smell.
And I get a pretty good idea at that point.
Are they good, are they not?
I will say my expectations were not super high,
having seen the prep, you know, having,
having seen the journey these beans have taken to get here.
If an arabica had taken a similar journey,
I would not have huge expectations.
The smell is getting me a little bit excited.
There is a kind of very sweet,
kind of caramel quality to it.
There is a little bit of floral kind of aroma,
is in there too,
and there's a kind of interesting peachiness to it
that's really quite appealing.
There is none, none of the earthy, woody,
rubbery kind of smells that you might expect
with other species, species like robusta,
none of the kind of weirdness you might've had
if you've tried some of the libericas out there.
At this point, I wouldn't know that it wasn't arabica,
but I'd be wondering what exactly it was
'cause it does smell a little bit different.
That is a lot of kind of very fresh peach.
I know I'm sounding a little pretentious, go with me.
That's really very pretty.
So now we'll put it into the cupping bowl,
we'll add our weight of freshly boiled water,
we'll steep for four minutes, we'll break the crust,
we'll clean it off, and then we'll start to taste,
and we'll have an idea what stenophylla could be
and could do for coffee.
My first taste of stenophylla.
Okay.
I'm gonna have another one first, I'll talk in a second.
One more, one more.
When you're tasting like this,
you're trying to taste through the layers
to get to what the coffee really is,
you're trying to taste through a roast
that might be slightly imperfect,
the processing that might've been slightly imperfect,
the prep, all of those things, you try to understand
what does the coffee itself taste like.
I think the first thing that surprises me about this
is that when it comes to arabica, higher-ground coffees tend
to have this kind of a lightness about them,
they're not very heavy and, and big.
They're quite light and quite delicate,
and this reminds me of that, it has a lightness to it,
it doesn't have a huge, heavy body.
It's quite light and bright and sweet and,
and kind of open and, and fresh-tasting, almost.
A lot of coffees, like robusta, or in many cases, liberica,
have a kind of heaviness to them and opposites to them
that's quite harsh and aggressive and,
and not clean and smooth.
This has that, which is really confusing to me.
It is not a perfect cup, how could it be a perfect cup,
looking at the journey that it's taken.
It has a little harshness to it,
but just might be a roast issue or a prep issue.
But it is ultimately a clean, sweet-tasting coffee
that has some acidity.
Got some florality, it's got some fruit to it,
a kind of stone fruit, a kind of peachy quality
that is pleasant, enjoyable.
It's a really nice cup, if I drank this,
I wouldn't think it wasn't necessarily arabica,
I would presume, my brain would only have presumed
that this was arabica.
It is, it is quite similar in quality.
The fact that this is from
an entirely different species genetically,
a long way away from arabica, is so interesting
and so unusual,
and actually fills me with a great deal of hope.
When we think about why this might be exciting as a coffee,
there are two reasons, one,
the straight passionate consumer in us would want
to drink something new and unusual in this species,
and I would love to taste this,
you know, harvested at peak ripeness,
processed really carefully, you know,
given a roasting, given a chance to dial in the roast
and, and bring the best out of it,
that would be exceedingly exciting to taste.
But that, I think, will always be a niche part of this,
a small piece of the market.
But the idea that that could be possible
within the next five years or so is very exciting.
I know that's not the instant gratification
that we all want and need,
but, but five years doesn't feel too far away
to be beginning to see this in a coffee shop, for example,
and that would be just so cool.
The work that is much more interesting
and much more important
is the work that will outlast the lifetimes
of the people doing it now.
It's thinking about the longterm future
of, of coffee production.
This makes me think that there is a chance
to have climate-resilient, great coffee.
It's gonna take a long time, you know,
years and years and years, breeding programs are slow,
but I think this is a very exciting beginning
to a breeding program that may produce truly excellent,
truly climate-resilient coffee
that hopefully finds a home all over the world
for producers who want to grow coffee
through the challenges that are coming inevitably.
I think we're allowed to feel a little bit excited,
feel a little bit positive
in the face of what is usually such depressing news,
of climate change.
I think there is potential here
for a great future for specialty coffee.
But now I'd love to hear from you
down in the comments below,
what unanswered questions do you have
about Coffea stenophylla?
I'll try and answer as many of them as I can
down in the comments,
leave them there, leave your questions,
I'd love to hear from you, but for now,
I'll say thank you so much for watching.
I hope you have a great day.