What does this adorable and thrilling new blush I just bought have to do with this?

and this...and this.

It's seaweed.

Or more specifically, agar.

Agar is a material that's made from some kinds of seaweed.

It's this gel-like substance that has all kinds of uses.

And, yeah, it's a big part of the cosmetics and skincare industries, used as a thickener and a stabilizer.

It's also used in agriculture as a soil additive to help soil hold on to water better.

It's even used in some restoration techniques to help conserve ancient and precious art pieces.

But would you believe this seaweed substance actually started out as a kitchen accident?

In fact, seaweed’s role in the kitchen is actually why it changed science forever.

Okay.

But to actually understand how agar, this unassuming powder that comes from seaweed, became such a part of all of our everyday lives we've actually got to talk to someone who's going to tell us agar's origin story.

Hi.

Hello.

Thanks for having us in your kitchen.

And that's a story that starts thousands of years ago and involves noodles.

So we’re going to make a seaweed noodle, called tokoroten.

delicious!

Yes, it's very nice simple jelly noodles.

Believe it or not, this seaweed noodle has been around since the Nara period.

We used to cook the seaweed for a long, long, long time, hours and hours.

But now we dry it out and then make a powder like this.

Much more convenient!

Yes.

So it just cooks for about three minutes.

So how did we get to this from seaweed?

A Japanese shogun was passing around the mountain one day, and he got caught in a very bad storm so he has to go somewhere to stay.

Yeah.

So he found finally an inn And they serve the most basic local foods Okay.

And that was the tokoroten Okay.

Oh, wow.

Because it's such a classic.

Yes, classic dish.

So after the meal, the innkeeper left the dirty dishes on the side of the room—relatable, to just leave the dirty dishes.

Exactly.

So the next day, innkeeper found leftover noodles dried out and also crumbly in the cold.

So then, he adds water to the dishes and they go back to slimy It rehydrated it!

Yeah.

They became like tokoroten again.

It was like, ‘oh that's kind of convenient!’ Yeah.

So just because this Shogun left some noodles in his dish and the innkeeper didn't wash them right away.

Yeah, he found a way to make this powder.

Yes.

That allows us to make this really common lovely dish much faster.

A little lazy, accident Gives me hope!

But still nowadays we’re using it all the time.

So that's how I grew up, making jelly, obviously, tokoroten, lots of, like, sweets from Japan.

and it’s much more refined as well.

Now this has much less seaweed, kind of distinct seaweed flavor.

Sure.

Or too strong odor, like smell, as well.

So it's much more clean.

Yeah.

And simple.

So it's not disturbing the sweetness.

Sure you can add other flavors.

Yeah, fruit, or— and they won’t overpower.

How’s our agar doing.

So now it’s starting to boil, right?

So then you're ready.

I'm just going to pour.

Okay.

Simple.

So just let it cool.

Woo!

Little bit tight.

Just a ‘lil tight squeeze.

You can do it.

Oh!

that happened so fast, that’s so exciting!

Oh.

That's fabulous.

And so how do you eat them?

Classic tokoroten is a savory one.

Oh.

I love it, I love how simple it is.

It looks delicious.

Ooh.

*slurp!

* You need to slurp.

That's the way to eat!

This tokoroten is good with the hot weather as well.

So it's not going to be melting as well.

Oh my God, yes!

And this special property of agar— that it doesn't melt in the heat—is actually why it changed science forever.

I’m going to sit down and enjoy my noodles here.

So, in the 1800s, one of the biggest challenges that science was facing in its day was how to grow microbes like bacteria and fungi in a laboratory setting, so we could understand more about them.

See, to grow microbes, you do have to give them something to feed on, something with the nutrients they need to grow.

Now people were doing this at first on things like a potato.

But as you can imagine, this was a little messy and uncontrollable and unpredictable So things got a little more sophisticated when they started using gelatin instead.

Now, gelatin is made from using animal hooves and bones, and it has a couple of advantages because it's pourable.

So you can pour it into whatever vessel you'd like to grow your stuff.

And it's clear, so you can really see your microbes are doing.

But it does have one major disadvantage, which is that it melts.

One of the main things about microbiology is that you need to be able to incubate things.

You put the microbes in a warm little cupboard so they'll grow nice and fast for you to study them.

But you can't put gelatin in an incubator because it'll basically just turn to soup.

In fact, gelatin is so delicate that it'll even goopify just on a hot day.

And in one particular lab in Germany, where they were discovering all kinds of bacteria and really needed a clean and simple way to grow them, the hot days in summer were messing up all of their gelatin, and they couldn't make any progress in their science.

But luckily, the answer to all of their problems actually lies in the kitchen.

Thanks to—enter stage left—Fanny Hesse.

Oh, sorry.

No, this is not Fanny.

Sorry, I'm not.

This is— Sue Bailey.

Thank you, Sue.

Thank you for being here to tell us about Fanny.

Yes.

Fanny was the wife of a frustrated German microbiologist who was having real problems growing microbes in the lab.

What she was doing was making beef broth for her family.

But of course, what was also happening was that the beef broth was used as a culture medium letting the microbes have their feed, as well.

So in her husband's lab, she's like making dinner for the fam.

And then also basically unpaid, unofficial research assistant.

A little bit like that, yes, but she was also a wife, a mother, and a scientific illustrator in her own right, and she was a clever woman.

So we're about to make gelatin and agar jelly so you can really see the difference up close and personal here I'm going to put some of this powder in this water... but why.

Because you have to let it bloom.

You have to wait for it absorb the moisture, and then you will be heating it so while we wait for our gelatin to bloom, we are also going to make its jelly counterpart in agar because this is a really big brain-wave that Fanny had?

Yes, because she suddenly realized that she was thinking of her neighbors, who were Dutch and they used to live in Java, in Indonesia, and brought back this substance agar agar, which was able to make jellies that would withstand the heat and like already we can see the difference with agar because it wants to come to a really high boil.

It does.

Indeed.

Whereas what we're about to do with the gelatin, we have to be so careful about what temperature it comes to.

*liquid hisses* Oooooohhh The gelatin is very sensitive.

If you are wanting your gelatin jelly to set, I'm afraid you've got to go and put it in the fridge.

And of course, in the 1800s, early 1900s, refrigeration kind of hard to come by.

Whereas, friend agar, you can make it set after about an hour at room temperature.

We love her.

Simple.

Oh, disaster as always.

Absolutely classic moves on my part.

I already see actually a bit of a difference because look that's quite cloudy.

Yeah.

And that one’s really nice and clear.

Oh my gosh you're so right.

So this is just winner all the way around.

Oh very much so.

It's the perfect medium.

Oh my God I love it.

I love that it came from the kitchen.

And all of these men trying to figure out the solution to this big scientific problem.

And then she's like, you know what?

Guys, try this.

And from the kitchen we come into my favorite place: the lab.

Today agar is sold for biotechnological purposes as this dried powder.

So this is from seaweed.

How exciting.

And we rehydrate that in the lab, so we add liquid back in and we pour it into petri dishes like this so that we can grow all kinds of lovely things and know more about them.

At the time, Fanny's agar solution for her husband's lab allowed them to discover the bacteria that cause really serious diseases like tuberculosis.

And like all good chefs, Scientists started tinkering with their recipes.

You see, agar is so hardy that you can add stuff to it really easily without disturbing it.

So scientists figured out that by adding or subtracting certain ingredients, they could determine exactly which kind of microbe would grow on a plate.

And that's exactly what we did in my lab recently.

This is a video of some of these special plates that select for specific kinds of microbes.

And this blue one here— one of my favorites— if something grows on this plate and it's this color, then we know it can only be the bacterium B. cereus.

No, seriously.

That is actually what the bacterium is called, it causes really severe food poisoning.

Now methods like these totally revolutionized medicine.

A medical professional could now take a swab directly from you, the patient, and grow it on a special plate like one of those.

Depending on what grows and how it looks when it grows, they can determine pretty much exactly what germ is making you sick.

And your medical team can even use agar- based plates to determine what treatment is going to be most effective.

So agar has come a long way from its humble accidental beginnings.

It's now commonly used all over the world, not only in personal cooking, but also in industrial food production as a stabilizer and thickener.

Add to that it's used in science labs all over the world, plus all of its other fun and funky uses like...insect farming.

Who knew?

Then it's no surprise that the world uses a lot of agar, meaning a lot of seaweed.

In 2019 alone, 3.7 million tons of agar- containing seaweeds were produced worldwide.

And that's just agar.

Seaweeds actually produce a whole host of really useful compounds in addition to agar.

So where is all this seaweed coming from?

Oh, this is exciting.

Okay.

Oh, my God, it's so heavy.

It's heavy.

Yep, two hands maybe.

It's a big boy.

Holy moly.

This is so much seaweed.

And it's just, like a tiny amount of what you guys harvested?

Two plants out of all of the plants that we hauled out of the sea.

So we grew this bad boy, in about 5 to 6 months from a microscopic little bit to this.

That's incredible.

And what does this particular kind grow for?

Like what are you growing it for, what purpose?

it makes a lot of really useful compounds, that you can use in fertilizer, the biopharmaceutical industry, beauty industry, that sort of stuff.

but we do also grow species that you can actually eat at the farm as well.

I mean, you could try eating this, but Yeah, that looks fine.

I will eat the green bits.

So it's crunchier than I thought it was going to be ooooooh very salty!

tastes like ocean.

Now, the word seaweed is simple, but it's actually a little more complicated than the way we've been talking about it so far.

Seaweed is a very general term for macroalgae, or the kind of algae that we can see with our naked eye.

But if we want to go simple, we can break it down by color.

Brown seaweeds are things like kelp, which is what Reina here works on.

Then we have green seaweed, like your classic sea lettuce and funky looking guys like this one.

And then we have red, the largest group of seaweeds, and species in this group are the ones that produce agar.

But okay, How the heck do you farm a seaweed?

Well it's a fairly involved process, so this is the big boy but it will make fertile material.

every species makes it at a different part of their body.

So this one here will get fertile patches along the little fringes here.

it's frill.

Yeah, exactly.

Fertile frill, let's call it.

We will collect fertile material from the wild, we take it into a nursery where we do the next steps of the processing.

Nursery!

So here we've got some fertile tissue.

and we put it in the fridge overnight and dried it out, basically, which means that this seaweed is very, very stressed.

So hopefully, as soon as we put it in the seawater, it will release all of its spores.

In the tube it goes.

and hopefully it will give us lots and lots of spores.

And they are so small It's kind of hard to see, but you'll be getting about, you know, 10,000 to 200,000 spores per milliliter.

So a lot of potential seaweed babies being formed right now, so.... You can see that some of them are already settling, so they're basically going from a teardrop shape when they’re swimming and then when they're ready to settle down, they get nice and round and fat and ready to grow.

And we leave them to their own devices, give them some food, and then they'll grow into what I'm looking at under the microscope right now.

So they are the sexual life phase, and we keep them only in red light.

because as soon as you give them blue lights, they will try and make babies.

We basically bulk up our cultures, so we can make them grow big and strong and once we have, really, really big cultures, we'll take them out of the red light zone and put them in the blue light, which is the cue for the little fellas to become fertile.

And then we seed them on to the twine that we have in the aquarium, So here we have one of our spools.

We'll put our cultures in here with the line, and we'll keep it here for a few weeks.

And it gets nice and big, and it attaches to this, twine over here.

and then we take that out to the boat and out to the ocean.

One of the main challenges at the moment for seaweeds is ocean warming.

So most kelps, particularly, are temperate species, they sort of like slightly colder water.

And actually, if you go to any sort of temperate coastline in the world, you'll find kelps.

They grow at about 25% of the world's coastlines, I think.

Well, we call kelps ecosystem engineers.

So they completely change the environment they grow in.

But everything's getting hotter, and they don't really like that.

So, there is massive losses of kelp worldwide due to ocean warming.

And we’re trying to figure out, how can we grow best and how can we grow it in a way that it would still be able to grow, you know, 50, 100 years from now?

Trying to figure out, you know, how to grow the seaweed so that, you will have the most amount of biomass.

but also trying to figure out how can we grow it so it doesn't impact the environment negatively.

So trying to research, you know, what types of other species does it interact with?

Are those the same types of species you have in a natural kelp forest or are they completely different?

We're starting to work on things like the microbiome of seaweed, which means that there's lots and lots of little microbes that live on the surface of the seaweed.

that might actually help them be healthy and, protect them against diseases and help them be more thermo-tolerant into a warmer future.

And with our colleagues here and with everyone all over the world, what we're trying to do is make sure that natural kelp will be around 100 years from now, and that we can grow seaweed 100 years from now, and we keep these fabulous ecosystems in place.

Stunning!

So whether we're farming it, preserving it in the wild.

using it for science and medicine or for delicious food, seaweed and all the cool stuff it makes is a central part of our modern world, and we've got to protect it, So I'm glad people like Reina are on the job.

And who knows, maybe the next big innovation in science is hiding in that old hand-me-down recipe you've got in your kitchen, or even in your dirty dishes that you left out too long.

We can only hope.

I’ll get another bowl.

Thank you, thank you.

Does anybody want any?

Me!

Can I have a little more?

Please help yourself.