Chef vs Science: The Ultimate Kitchen Challenge

Welcome to a cooking competition like you've never seen before.

In one corner, two-Michelin-star chef Marcus Wareing.

At the end of the day, it is a lot of training,

a lot of hard work, but also a lot of love and care and understanding.

He's a top chef at the height of his powers.

The only thing that is going through my mind now is flavour.

In the other corner, there's me - Mark Miodownik.

A material scientist...

..from University College London.

During the course of this contest, I'm going

to use science to try and cook better than Marcus.

You're saying I'm destroying flavour?

Cooking does destroy flavour.

We're going to cook exactly the same dishes...

but using different methods.

That is the soup - I guarantee your brain will explode.

I'll be using equipment from my lab...

..and techniques based on the understanding

of cooking at the atomic level.

-We're going to have to snip them up.

-What?

By a molecular scale.

Marcus has flare!

What I want to do now is just control it.

-Passion.

-There's a lot of herbs in there, there's a lot of butter in there.

And experience.

I'm listening to it, I want it to sizzle.

The question is -

which approach will create the most flavoursome food?

You've ruined it, it doesn't work, it's disgusting.

It's disgusting?!

As we go through our competition, I'm also exploring

the science behind our experience of food.

What is flavour?

Woo! That is so strong.

And how can we manipulate it?

This is laughing gas.

Ultimately, the question that lies

behind our competition is this....

..is cooking a science...

..or an art?

Can Mark, who's not a chef - a scientist,

a professor - cook better than me?

When I wake up in the morning thinking I'm being

challenged like that, it gets me worried, but I'm also excited.

I'm nervous.

I'm up against Marcus Wareing, he's a great chef

and who am I? I'm a keen cook, I'm a scientist.

On the other hand, I mean, I'm a professor of materials and

we're talking about food and food is edible materials, isn't it? So...

So I know about that.

The challenge is incredible. It's all about food, it's what

I do every day, it's what I've been doing for the last 30 years.

I've got access to lots of kit,

ways of taking the flavour from food and making new tastes that

I'm pretty sure he will never have come across.

But I mean, am I really saying that I can tell Marcus something about

taste and flavour that he doesn't know?

I guess I am. I am saying that.

Over the next hour and a half,

Marcus and I will be cooking up

some of the nation's best-loved dishes -

from starter to dessert in a head-to-head contest.

I'll do it the science way, Marcus will do it his way.

And since it's Marcus I'm trying to persuade,

it will have to be him who judges which dish is best.

In my corner, I'm backed up by chef Antony.

Marcus has got the very able Jane.

So...ding-ding...

..round one.

Our first item on the menu is tomato soup.

The ambition is to create a soup that is rich

and warming yet light, with an intense tomato flavour.

So, Marcus... what makes the perfect tomato soup?

From a chef's point of view, the perfect anything is

only from the perfect ingredients.

And the core value of this particular ingredient is, for me,

as a chef, is what does it taste like in its natural state?

Cut it, taste it, cos then you can know what to do with it.

There is one main problem with making tomato soup -

tomatoes are 94% water,

so the flavour in each individual tomato is very diluted.

So the challenge is to extract the maximum

amount of flavour from such a watery fruit.

Marcus is taking a traditional route.

As a cook, all I'm thinking of in my mind is, "Right, what do

"I need to do to bring the best flavour out of these ingredients?"

So what I have done is I've put a hot tray onto the stove, I've cut up

my tomatoes, I've dropped them into the pan with a little bit

of oil. I've put then into there some sliced onions and some garlic.

The onion and the garlic is

a lovely accompaniment towards the tomato,

it brings out that flavour.

Some seasoning and now, erm, that... Jane is going to put

that in the oven for me, cos I want to slightly roast it.

I'm looking for a slightly different flavour than just plain tomato.

So Marcus is getting rid of a lot of the water inside his tomatoes

by roasting them.

Inside the oven, much of that water is now evaporating,

reducing the tomatoes and therefore concentrating their flavour.

But do you know what? I think Marcus has got it wrong.

I can understand reducing a tomato from a lot of its water...

-Yep.

-..but it concerns me that all of these cooking processes

are destroying flavour and a lot of what's coming off them

is the very thing that has that tomatoey-ness,

you know, that real....

So you're saying that because I'm cooking...

I'm destroying flavour?

I think, I think you... Cooking does destroy flavour.

-That's an interesting theory.

-Isn't it?

-Cooking destroys flavour?

-Yeah.

I've got my own take on this.

A scientist's take.

For me, when you cook something, you don't just lose water.

You also risk evaporating some

of the volatile organic molecules

that help create the flavour of tomato.

So I am going to make the perfect tomato soup without

any cooking at all.

I've set myself a task of making a better tomato soup than you

and obviously that seems like quite a lot of bravado given

that you're a Michelin-starred chef.

-Yes.

-But I've got a trick up my sleeve.

I'm going to use this piece of kit from our lab in the university.

So it's a centrifuge,

which basically whizzes around this tomato,

chopped-up tomato. And it separates it by density.

What's it in?

Chopped-up tomato in here, into the centrifuge,

whizzes it around, it'll separate the tomato by density

and then we'll be able to distil pure flavour.

Pulp goes away, left with the liquid, and then what?

-What happens to the liquid?

-Oh, that is the soup.

I guarantee you'll...

Your brain will explode.

First, I'm using a hand-held blender to break down

the cell walls of the tomato.

This allows large protein molecules to be

attacked by enzymes in the juice, reducing them

to thousands of much smaller molecules of glutamic acid.

It may not sound very nice, but glutamic acid has a rich

and savoury flavour. It's one of the things that gives

tomatoes their distinctive taste.

Mark, why did you take the skin off?

Cos, actually, we're creating flavour now.

Sorry. You're creating flavour? How are you doing that?

We're not creating... The enzymes are creating the flavour by

reacting with some of the...interiors of the cells.

Just... Do you know what?

Yeah, I don't know about you guys, but the first thing... When I look

at that and I see the colour of it, it just says bland to me.

-Yeah.

-Yeah.

And I think in my head... I think tomato, I think deep red...

And I've got this picture of flavour in my mind of what I want

to taste on my palate and when I look at that, I am...

I... I can't imagine how that's going to taste.

-Hold that thought, Marcus.

-I am going to hold the thought.

OK...

-Can I smell that?

-Sure.

-Smells different.

-It's getting better, isn't it?

It smells very different to when it was on the board.

-That's the enzymes.

-That is the enzymes.

That's, that, that... Now you've got my attention

because I didn't think that would smell as good as that.

You're making me worried now, I'm starting to...

-LAUGHTER

-Hey, we've got him.

Table's turning, I've got this feeling. I'm shaking my soup.

It still tastes good. It still smells good.

But it's fascinating, fascinating.

But there's more to come. Time to pop my tomato mush

into the centrifuge.

Speeding up. 300 revs per second, 400, 500.

So they're whizzing round now.

1,000. So if you trained for space you'd be in one of these

machines, yeah, cos it's essentially like creating a different

form of gravity, pulling things down, but we're pulling them

in opposite directions.

We're going to get up to about 7,000 revs a minute.

The tomatoes are spinning round at such high speed

that different parts of the tomato separate out.

After about an hour, this is what we get.

So you get this pulp which has been separated by weight and then

you've got this beautiful liquid - clear, absolutely crystal clear.

-It's the liquid I'm after.

-So what happens now?

What happens now - we're going to turn it into a soup for you,

so we're going to strain it through the muslin, we're going to put it

into a pan, warm it up, season it...

and you've got your tomato soup.

I'm discarding the pulp

because it's mainly made up of cellulose or fibre,

which contributes

little to flavour and doesn't even break down in the human gut.

It's the remarkable liquid I'm interested in.

Because concentrated in this are all those tiny molecules

of glutamic acid dissolved in water.

This liquid should be full of tomato flavour.

But what sort of temperature are you going to go to?

To about 70 degrees.

The hotter it gets, the more we're going to lose a lot

of the aromatic flavours, a lot of the real heady stuff.

-That's all gone in yours, I mean...

-Yeah.

..that's long gone, but we've got it.

That is a very, very surprising flavour.

That really packs a massive punch.

It's almost transparent, it's not...

And you're expecting that to

be totally flavourless and that's not what you get.

I'm not expecting flavourless, but if I was in a restaurant

and I asked for a bowl of tomato soup, which is what this title is...

-Yep.

-..I think I'd be very, very surprised

if that got put in front of me.

Yeah, you would be surprised.

Because that's not what I ordered. Cos that's not soup.

But you wouldn't reject it without tasting it.

-Do you know, I think I would.

-You would?

-Yeah.

It's not a meal and a soup is a meal, it is there to fill you up.

That won't, it's just liquid.

'OK, Marcus, understood... but at least have a taste.'

-You're happy with that?

-Yeah, I think it's great.

I think that's bland, I think it's tasteless, I think

you need to try harder. That's not good enough.

I'd be seriously, seriously disappointed if I got presented that

in any restaurant.

Just the fact that you've tasted it and seasoned it

and said you're happy tells me that you're not a good cook.

Well, I'm not a chef, that's for sure.

At the end of the day, if you break it all down, it is

a lot of training, a lot of hard work but also a lot of love

-and care and understanding. And I think that's what was missing.

-Ah, OK. Ah... That's what it is.

That's what was missing at the beginning, you didn't really love

and understand that tomato.

-OK.

-Mark, you didn't even taste it.

I want that soup to give me a hug. Turn that into a comfort soup.

-Comfort?

-Comfort.

-You want comfort?

-I want comfort.

-OK.

I'll turn it into comfort.

Antony, it didn't turn out so well on that tasting front.

LAUGHTER We've got work to do!

I may not have nailed it first time, but Marcus is giving me

a second bite of the cherry. A chance to improve my soup.

Trouble is, the only way I can see to do it

feels a bit of a retreat.

You're going to now do the opposite of what you said you were going

to do - and that's cook it, to reduce it,

to enhance its flavour.

-You've forced me into that, though.

-I know.

-LAUGHTER

-Very good, in't he?

Yes, I've managed to extract pure flavour from the tomato.

But despite that, my soup is just too dilute.

There's too much fluid.

So, frustratingly for me,

I'm having to resort to a more traditional approach.

Boiling off some of that water should lead to

a concentration of those crucial molecules of yummy glutamic acid.

Hopefully I won't lose too much flavour as the volatile compounds

evaporate off at the same time.

And to even things up, I'm going to add a few

other ingredients, just as Marcus did, for added flavour.

There you go, there's my tomato soup.

Oh!

-Very, very different.

-Yeah.

-Very different.

-There you go, that's yours.

-Yeah, OK.

'Let's have a taste of Marcus's soup.'

It's comfort, it's definitely comfort, yeah.

'And now the big test - what does he think of mine?

'Have I been able to produce a better tomato soup than him?'

Mate...

What you've done here, Mark, is that you have taken the bland liquid that

I had earlier on and you've reduced it and you've taken this soup

to a new level of flavour, which is what I'm looking for as a chef.

I suppose the question is - is this soup better than my soup?

The answer for me is no - I think that is a far better soup.

You know what I think, though, that I...

I know that, for me, that tastes good because I wanted...

It's the way I wanted it to be,

but I'm standing here staring at this thinking,

-"I want to work with this..."

-Good.

"I want to do something, I want to do something

"with this dish." And I'm thinking, "This does take me and can take me

"down to my holidays, being in the South of France, being in Italy, sat

"on a veranda, maybe even chilled, little glass of beautiful local wine

"to sit with it." You know,

I'm excited by your theory and I'm excited

by this machine and I will go away today thinking about this dish

and I'll wake up tomorrow thinking, "How am I going to make it better?"

I think from a non-chef point of view, you've taken it to

another level. I think it's really good.

'OK, I'll take that.

'I may not have outcooked Marcus,

'but it feels like I'm in the ball park.'

Yeah.

In the end, I did produce a powerful new taste sensation.

But I had to take on board some

traditional cooking techniques to get there.

BEEPING

As well as our competition in the kitchen,

I'm travelling the country looking at the science behind

some of the most intense and intriguing flavours.

I'm going to start with one of the most powerful flavours

I've ever tasted.

I remember when sushi used to be one of the most exotic foods around.

I was in my 20s before I even tasted it,

but now it's in every supermarket.

And when you open a box, one of the key ingredients is not

immediately obvious, you have to search around for it.

And it's this. Wasabi.

It's really strange stuff.

Unusual flavour, quite strong...

Woo!

Gone up my nose into just that bit of my head and now it's gone again.

I loved that when I first came across it.

But what if I was to tell you that this is a fake,

that there is virtually no wasabi in this packet?

This is horseradish, mustard, green food colouring.

And typically, a sachet of this stuff contains 1% real wasabi.

The vast majority of wasabi sold in this country is effectively fake.

But why, when supermarkets could presumably have the real thing?

And does it matter anyway?

Does the real wasabi taste any different to the one in my lunch?

-Hi, Nick.

-Hi, Mark, how are you?

-Pleased to meet you.

'I'm in search of the real wasabi flavour.'

So I'm on my way to the UK's only wasabi farm.

Because the secret to the flavour of the wasabi

is the wasabi plant itself.

-So it's a slightly secret location.

-Ah-ha.

'Nick Russell has been growing wasabi since 2010.'

Oh, that is a lot of water.

-Yeah.

-What? Is this a stream or something, or...?

Effectively, yeah, it bubbles straight out of the ground.

Wow. So these are the plants?

Yeah, so these ones are still relatively young.

They've been in here for about a year or so.

Wasabi is normally grown in the high mountains of Japan,

along streams that are rich in minerals and oxygen.

Conditions that are almost impossible to replicate

in gloomy old England.

Here it is.

But Nick has achieved it, and the results are spectacular.

He has tens of thousands of plants growing here in these enclosures.

And this one is ready to harvest.

So how old are these plants?

-These ones are around about two years old.

-Huh.

Erm, they're about ready for harvest.

So where's the wasabi? Where's this magical stuff?

The part we're looking for, the jewel in the crown, so to speak,

is the rhizome, which is effectively an elongated stem of the plant.

We'll give them just a little bit of a wiggle.

-There he comes.

-Yeah. Wow.

We'll get loads of little offshoots, but that's the real...

So these are the roots and that's the rhizome?

-Yep.

-And that's where the wasabi is?

-Exactly. Let's clean 'em up and take a look.

-Sure.

I can really start to see that familiar wasabi green coming out.

Yep, definitely. And as we grate it, that colour will really start

to come through.

Because it requires almost atomic levels of precision

in controlling the growing environment,

wasabi is one of the most expensive plants in the world.

I'd guess that that one is around about, erm, probably about 100g.

-100g?

-Yeah.

-OK.

And how much could you sell that for?

£250 a kilo.

Oh, OK, so that's about £25, then?

Pretty much, yeah. Yeah, at a guess, yeah.

Wow.

That's not a bad harvest, is it? Especially if you look around,

how many of these there are...

-That's why this is in a secret location.

-Yeah.

Yeah, we do try to keep it under wraps a little bit.

The key to experiencing the real wasabi flavour is its freshness.

So what we're going to do here is grate some of this up.

'It's all in the grating.

'The simple act of grating breaks down the cell walls,

'releasing an enzyme which creates intense flavours

'and oils called isothiocyanates.

'It's these oils that pack the wallop.'

There we go. There's a lot more of a natural green

-and you will start to smell it quite strongly...

-Yep.

..as well.

-So there we go.

-Is that going to blow my head off?

-We'll find out shortly.

-OK.

Yeah, a little bit of blowing.

Yep.

-Woo, that is so strong.

-Mm.

That is... That really clears your nose.

LAUGHTER And your taste buds, whoa!

Yeah, it really does,

it really does get you right up in the sinuses, doesn't it?

-Yeah.

-Yeah, yeah, yeah.

It's amazing that, erm, a simple grated plant can do that.

Yeah, right up your nose, isn't it? Woof!

It's a fireball.

But quite a solid, sweet aftertaste with it.

Yeah, you're right, yeah. Yeah, and that's...now it's dying down.

OK, yeah, and it is sweet, yeah.

I'm getting a bit of that stuff you get with

a bit of whisky in your stomach, now.

-Yep, warming.

-Yeah.

-Yeah, it's good.

I've never tasted that effect from wasabi before. While I'm

remembering all this, I want to just compare it with shop-bought.

OK, so a much more vivid green colour.

Yep, so a lot of colouring in that.

A different consistency.

Oh, yeah, a sort of... Creamy, that's what I recognise as wasabi,

-that's a totally different flavour.

-Completely different, yeah.

None of that vegetably, raw grassiness at all,

it's much more processed, much more...

The whole chemical process we're putting together here,

-you can't recreate in a packet.

-But here's the rub.

It turns out that wasabi's unique flavour comes from chemicals

that are highly volatile - meaning they quickly turn to vapour

and vanish.

Within just a few minutes, the wasabi hit has

dwindled away to virtually nothing.

20 minutes have gone by,

that wasabi should be a totally different beast now, shouldn't it?

-Yeah, yeah, for sure, yeah.

-OK, let's try it.

Mild. Yep, no blow up the nose.

-Slight touch of sweetness.

-Sweet.

Yep, if you were to sort of mow the grass early spring,

this is how you think it might taste. That's really it.

Um, but, yeah, it's lost all its power.

That chemical reaction we were chatting about

has dropped away completely. It's just the aftermath, effectively.

So you've got to make it fresh in order to get the real wasabi.

How do you do this in a Japanese restaurant?

I think predominantly it's grated at the table,

so you do have that reaction right with you there as you're dining.

And I guess that's why...

the kind of shop wasabi hasn't got the stuff in it.

'So as well as being incredibly tricky to grow,

'it also needs to be super fresh.

'That's why, even if money was no object,

'the shop-bought wasabi has to be imitation.

'The vast majority of wasabi plants grown here

'are destined for the very best restaurants in the UK and abroad.

'In some cases, selling for up to £5 for a teaspoonful.

'That puts it beyond the pocket of most of us.'

Now that I've tried the real deal,

the idea of eating my sushi with a synthetic wasabi

doesn't seem so appealing.

On the other hand, I am an academic,

so it's going to have to be a rare treat.

Before we get to the next round of our competition,

I've got an intriguing experiment I want to try out on Marcus.

Could the taste of champagne be affected

by the shape of the glass it's served in?

'I've asked him to decant identical champagne

'into a short, fat glass called a coupe.'

Lovely.

'And two slightly different tall, thin glasses.

'A flute...'

This is completely different.

'..and a tulip.

'He's going to need persuading

'that the shape of the glass is important.'

With my experience, it's the balance between flavour and fizz.

Yes, the glass comes into it,

but I personally am not 100% sure how important the glass is.

I thought I'd just ask you to taste each one of these champagnes for me

to see if you think there's a different experience.

The one that stands out as being completely different

out of the three is this one.

It almost has a flatness about it.

It's sort of started to...

..go to sleep, flatten.

And my thought process in my head, the bubbles, the flavour,

seems to have that better experience

through these particular two glasses.

'Marcus can't immediately tell which glass is best

'but has no problem identifying the worst.

'It's the short, fat glass, the coupe.'

So what's happening inside the glass to make such a difference?

Well, it's all about the magic of bubbles.

Champagne bubbles are full of carbon dioxide,

a gas made while the drink was being fermented.

When the bottle is sealed, the gas stays dissolved inside the liquid.

When the bottle is opened, the gas escapes as bubbles.

Where bubbles come from is really odd.

This is micro-imaging of a scratch on the surface of a piece of glass.

You can see how tiny imperfections like this

are generating bubbles.

And that has dramatic consequences.

These are where the bubbles are coming from,

these are little bubbles, they're being nucleated

and this is the little scratch. You get trains of bubbles coming out.

They look like they're coming OUT of the scratch.

What the scratch is doing is creating a little cavity

inside the liquid where there's a different environment

and the carbon dioxide is reacting differently to it there

and it will depend on the size of that.

-Big scratches aren't effective, it needs to be a certain size.

-Really?

But also, you get dirt, little bits of dirt can be your best friend.

A dirty glass can be a better glass, in that sense.

I'm not so sure about that!

But these little bits of...

They can be little bits of cellulose from someone cleaning the glass,

tiny fragments, I mean, microscopically small,

-but they can be very effective at nucleating bubbles.

-Right.

By putting coloured dye into the champagne,

you can clearly see what the bubbles are doing...

..and how they affect the taste of the drink.

As they travel up, they create vortices and the liquid,

the champagne liquor,

is now moving and that's developing flavour.

And in the coupe, you can see this shape.

It's obviously developing it in the middle,

but on the outsides, they're kind of dead zones.

So that's part of the reason why that's a very different experience

from these two which, if you look at them,

we're using the same technique,

you get the whole of the glass in that mixing, developing of flavour.

So bubbles have a crucial role

in mixing flavour inside the glass

but that is only half the story.

High-speed photography reveals another major role of bubbles

in the experience of drinking champagne.

When the bubbles get to the surface,

they've collect all these flavour molecules, and they burst.

And that bursting is really quite dramatic.

And here's a little video which shows how far

they can ping tiny bits of liquid up into the air.

Here's a bubble hitting the surface

and up it goes, it's launching a mist...

..and that's the mist you smell

before the liquid even hits your palate.

So this is where we talk about the "nose" of a drink of champagne.

It is dancing around.

I suppose when you drink it straightaway and it's still fizzing

you can sometimes taste the little bits of champagne

-on the end of your nose.

-Yeah. You can see why this coupe can be a bit flat

because a lot of those droplets are diffused. That mist is diffuse here.

But these two, these two look quite similar on that effect,

but actually they're subtly different.

This one comes straight up and all of that's funnelled straight up.

Whereas the tulip is taking a lot of mist

and concentrating it into the nose

and that's the logic of this glass here.

Arguably, this is the superior glass to drink champagne with.

Because it brings it...? Does it roll it round, do you think?

It's bringing it together, it's concentrating that mist.

'So, for me, the next time you visit a posh restaurant,

'you should be as worried about the shape of the glass

'as the quality of the champagne.

'Because different-shaped glasses

'affect the intensity of the flavour.'

We're back in the kitchen for the next round of our competition

and this time it's all about who can cook the best steak...

..medium-rare.

But first things first. Which cut of meat?

For me, my first choice is going to be a ribeye steak,

for many different reasons.

This has this incredible marbling of fat that goes through it,

there's a succulent value.

And what a chef's looking for is that great meat,

great marbling, but also, a fabulous fat content.

Who am I to argue?

This is what the perfect medium-rare steak looks like,

with a lovely pink interior

and really crispy, delicious outer shell.

But this combination is tough to create -

it's easy to leave the outside not done enough,

or the inside too done.

To succeed requires precise timing and temperature control

every step of the way.

'Now, I think I can achieve that precision

'through a novel scientific procedure.

'Marcus, however, relies on instinct and, well,

'yes, years of experience.'

My job as the chef is very little - searing, colouring it,

getting good flavour on the outside, and just allowing it to rest.

I don't need to do a great deal.

I've set myself a task

-of making an even more delicious steak than you.

-Right.

But I am going to use a deep-fat fryer,

I'm going to use liquid nitrogen

and I'm going to use a water bath.

I'm doing all sorts of things to this steak.

I'm actually using a very complex process

in that quest to even get a more delicious flavour than you.

'Right, Marcus, do your stuff.'

Pan's nice and hot,

bit of oil,

seasoned side down.

Seasoning again.

-Turn it over, that's been in the pan what, 30 seconds?

-Yeah.

Bit more oil.

So now I've got to concentrate,

I've got to stay focused,

I've got to get the temperature right.

Now, I've got that under control. I've got the pan roaring hot.

You know what's also interesting here?

What I'm also taking on board

is the sound and I'm listening to it,

I want it to sizzle. If it's not sizzling,

then it's at the wrong temperature, and I have to do something about it.

The other thing is when you put your salt on,

never put the salt on and leave your meat to sit on the side.

The salt's going to start to cure the meat,

it's going to start cooking it,

but it's also going to bring out the water.

Which then, when you put it into the pan, it's going to dilute,

and it's going to cool the pan down straightaway.

What you want to do is keep it at the optimum temperature

for as long as possible. Just throwing in some garlic now.

Everything I'm putting in the pan now,

it's going to scorch a little bit

but it's also going to start adding a bit of flavour.

Some rosemary.

Some thyme and bay leaf.

Best bit is some butter.

Plenty of it.

What I want to do now is just control it

and rather than searing the meat, I'm now starting to cook it.

I don't want the butter to burn,

so I've got to bring the temperature down and get it under control.

A little bit more butter in there.

See, you can turn around and say

"There's a lot of herbs and butter in there."

The only thing that's going through my mind now is flavour.

-No, I'm with you.

-Flavour.

-I'm with you 100%.

If you're going to order a steak,

if you go to the trouble of killing an animal,

you should eat it at its most deliciousness.

'Inside the pan, the surface of the meat

'is undergoing an incredible transformation.

'Proteins and carbohydrates react in the hot oil

'to produce chemical compounds called ketosamines...

'..which then dehydrate into something called reductones.

'It is these caramel-like chemicals

'which produces the incredibly rich

'and savoury flavoured outer crust.

It's known as the Maillard reaction.

Smell that.

That's good.

Oh, that's great...

-My job's done.

-Yeah, wow.

All I need to do is just let it sit there, rest

and watch you cook yours.

Your turn.

You got the Maillard reaction to work on both sides,

flipping it back and forth, and that's fantastic,

you've managed to get a large amount of flavour.

What we potentially can do when we deep-fry it

is actually get the Maillard reaction

to happen evenly all around the sides.

So one of the things we've got going for us

is that we will have more area of flavour.

Ah-ha!

I can see you're worried!

-Um...!

-No, I'm not.

'Well, we'll see.

'My approach involves an innovative and complex scientific process.

'The first stage is to vacuum-pack the steak...'

Love these machines.

'..to seal in the juices.

'Now, into a water bath set at precisely 55 degrees,

'using a method of cooking called sous-vide,

'which is relatively well-known to chefs.

'Inside the bath, heat is moving from the water to the steak,

'gently heating it to 55 degrees from edge to edge.

'Now, this is the exact temperature at which beef is cooked medium-rare.

'S, one hour later, my entire steak is cooked to perfection.

'We could eat this right now,

'but we don't have the nice charred stuff on the outside

'that gives steak its wonderful flavour.

'So here's my problem.

'How can I create that crispy outer shell

'without cooking the inside any further?

'Well, this is where the real science comes in.

'I'm going to protect the inside using liquid nitrogen.'

I understand the process of the water bath

and the deep-fat frying,

but I'm really struggling with why you need liquid nitrogen.

I'll try and draw a diagram, because it's how my brain works,

but, essentially, the theory is this - here's the steak,

we've cooked it perfectly as mediumrare.

But now, we need to create all this flavour

and we're going to deep-fat fry it, but as we deep-fat fry it,

the outside is going to be very hot,

and it's going to start cooking all this in here

and it's going to get dry and not be so delicious.

So we want to create a barrier to that

and that's why we put it into liquid nitrogen -

all this is going to be frozen.

And if we get the thickness of that layer...

that frozen layer, it gives us time.

It gives us time on the outside while it's in the deep fat

to get the Maillard reaction to happen all the way around.

And, of course, getting that thickness right is how long

we put it into the liquid nitrogen.

The longer we put it in the liquid nitrogen,

-the thicker that layer will be.

-Right.

If we can finish the Maillard reaction by the time this is thawed,

we'll have a perfectly cooked steak in the inside,

and perfectly delicious on the outside. Da-da!

You have a massive risk here of serving steak

that's going to be beautifully coloured, it's going to look great,

it's going to be soft and perfect on the centre,

but you could have this inner layer of it being frozen.

That is our big risk. I agree with you.

Ah, I found it! I knew there's going to be a point of...precision.

The precision of my cookery

is identical to the precision that you have.

You've got it in your hands and your eyes,

and we've got it in these measurements.

Mark, this is the first time you've actually started

to look like a scientist.

I'll take that as a compliment.

Goggles, gloves, shirt...

'Timing and precision are paramount.

'Remember, the aim here is to stop the inside of the steak

'from being cooked any further by freezing the outside

'to create a kind of a protective barrier.'

OK.

-Right, you ready for 30 seconds?

-Yeah.

'We've had to rehearse this

'but I think now we've got our timings about right.'

In we go.

Must be close. Are we?

21, 22...

..25, 26, 27,

-28, 29, 30.

-OK.

How long in the fat now?

Well, we've got to try and get the Maillard reaction to happen...

There we go!

Getting there, getting there,

getting there, bit more.

Yeah, ten seconds more, I think.

-TIMER BEEPS

-There you go.

-Yep.

Out she comes.

Done.

HE LAUGHS Your perfect steak, Marcus.

I've got to say, it looks pretty good.

I think that's ready for eating.

-Yeah, I think we need to eat that now...

-Now!

'Will my steak taste as good as Marcus's?

'Frankly, I'm a bit worried about all the extras he's added to his,

'especially all that butter.'

Try it?

Can I?

THEY CHUCKLE

It's very good and it works.

So you have achieved everything that you wanted to achieve.

It's not frozen, you've got the colour,

you've got it cooked perfectly well,

I'm racking my brains to find a fault.

-Wow, that is, um...

-I suppose it's my turn.

-Yeah!

-Try it?

-Yeah, I'd love to.

That, for me, has a better flavour.

But I think this process is fascinating.

I think it's intriguing, it's exciting,

I'm looking at the same cuts of meat,

completely different colour.

I know why that tastes better and it has a lot to do with the butter,

all of these herbs and probably the quantity of seasoning

that I've incorporated into the cookery.

But I think that's brilliant.

'Well, you know what? My technique worked.

'From a technical point of view, the steak was perfectly cooked.

'My science-based approach is getting closer to Marcus's standard

'but it's still not quite there.

'Using a deep-fat frying pan to create the Maillard reaction

'meant that I couldn't use any butter or herbs.

'So cooking steak the traditional way

'can still give you more flavours.'

What is the perfect steak without the perfect chip?

Crispy and golden on the outside,

hot and fluffy within.

Normally, you'd just use a deep-fat fryer,

but science can improve on that?

So, before we go to the next challenge,

I want to show Marcus how science can make the perfect chip.

You're fast.

Even at peeling, I can't match Marcus.

'Proper chips are cut thick

'so each chip has got a large surface area

'for the hot fat to work on.

'It's this reaction that makes the chip crispy on the outside.

'But I think I can increase the surface area of each chip,

'and, therefore, make them even crispier.'

I'm going to get this water here. I'm adding some salt to it.

'First, the chips go into a bag with a bit of salty water.'

So, in goes the salty water.

Right, so vacuum-packed with the brine in there.

-Right, that's what that is.

-Yep.

So now, it's going to go into the water bath.

'This is sous-vide cooking,

'the same principle as the steak.

'Careful temperature control means the inside of our chips

'are perfectly cooked, light and fluffy.

'They will also be infused with salt,

'so, in theory, they won't need any seasoning.

'I've got the inside just right. Now the tricky bit.

'How to make the exterior even more crispy than usual?'

So, after 15 minutes, Marcus, this is what they look like,

and feel like. You can see that they're now delicate

so we've got to be really careful.

We're now going to try and roughen the surface up

in order to give us more surface area to get more crispiness

-in the final stage of cooking.

-Right.

And we're going to use something called an ultrasonic bath.

And what this does, it fires sound waves at these chips.

It's like firing mini torpedoes at the chips

and their surface will start to break up.

All I see is a piece of metal and some water. How does it work?

I'm still struggling cos I don't see anything in there.

It's exactly like sound, but it's a pressure wave

that you can't see and hear

but it's travelling through this medium.

So it's a bit like playing music that you can't hear.

-But the potatoes can hear.

-It's pretty pointless.

No, because it's singing the song of the potatoes!

Off we go.

Would you believe this machine is often used to clean jewellery,

but here, ultrasonic waves are moving through the water,

creating tiny air bubbles on the surface of the potato

which then burst.

It's a process called cavitation.

Frying this expanded surface area

should give the chips incredible crunch.

'Now for the deep-fat frying.'

I've got to say, I've never known anyone

to be so delicate with chips as you.

These are the perfect chips!

I'll never cook for a Michelin-starred chef

in my life again, I'm pretty sure. In they go.

In theory, they shouldn't need seasoning.

The perfect chips.

Go on.

What I find amazing is the seasoning point of view.

It's quite unusual to have a potato

-that's penetrated with salt like that all the way through.

-Yeah.

What we always do is try and get a potato crispy or a chip crispy,

We think, "We'll leave it in the deep-fat fryer a bit longer."

Eventually, it will come out, it will be crisp,

but it will be soggy within a matter of seconds, straightaway.

They look like that chip, but they've actually stayed very crispy

so your theory... your theory has worked.

The chip.

-Great flavour.

-We'd better leave some for the crew.

-No.

-No, I don't think we should.

-MARK LAUGHS

They're still crunchy. Mm.

-Happy now?

-Very happy. HE LAUGHS

I'm back on the road. This time, I'm in search

of a deeper understanding of what we mean

when we talk about flavour.

How it's formed,

what it is.

I think, to figure it out,

you need to understand the taste processes

going on inside your brain

and not just the obvious ones.

If I was to ask you how you detect flavour,

you'd probably mention your taste buds

and you might also say, "Well, sense of smell's important too."

But there's another sense that's vital - the sense of sight.

Colour messes with our senses

in all sorts of complex and surprising ways.

In fact, there's a theory that not only does colour influence

our perception of flavour,

it can actually CHANGE flavour.

So I've come to Greenwich Market in London

to put this hypothesis to the test

and to hand out some ice cream with a difference.

First things first, I've got my jacket,

I've got my hat,

and I've got...

ice cream.

It's home-made,

it's strawberry, and it smells delicious.

Can I interest you in some ice cream? Free ice cream?

'Luckily, there are quite a few people here

'who are willing to try some free samples.

'But do they recognise the flavour?'

It's not a trick question.

Strawberry?

Strawberry.

Is it strawberry?

-Strawberry.

-Yes!

So far, people have been very happy

trying my red strawberry ice cream

and they've had no trouble identifying the flavour.

But what if I offered them one of these?

'What I'm really interested in

'is what effect the colour of the ice cream has on its taste.'

You, sir, can I give you the blue?

Somewhat like mango. Is it?

Butterscotch or something?

-I ain't got a clue.

-I want to say banana, but...

-Is it kiwi?

-Banana.

-Raspberry, maybe?

-It's a kind of nut.

-Peanut butter?

-Strawberry.

Strawberry! And you?

Vanilla.

People have really enjoyed the ice creams I gave them,

but they almost all got the flavours wrong.

And that's because my multicoloured ice creams were a bit of a con.

Regardless of their colour, they were all exactly the same flavour

and that flavour was strawberry.

The power of the human brain is incredible -

all of our senses are bombarded with information.

But sometimes that can lead to confusion.

Better try this myself.

It's so weird.

That does not taste of strawberry at all.

It's like there's just too much information for my brain

to kind of handle, so it's kind of taking a short cut.

It's skipping over one sense

in order to favour the other, so what my eyes see

is not what my taste buds detect

and it's just going with what my eyes see.

Very strange.

OK, so far, I've been dealing with

how the way we see things can actually change the taste of food.

But later on, I'm going to really up the ante...

..with an experiment into how a very different one of our senses

may affect what we taste.

Our sense of hearing.

But right now, before our next challenge,

I've got some more surprising science to show Marcus,

and it's all about red wine.

Normally, and for me, ANNOYINGLY,

we're told to let it breathe before drinking it.

But that can take half an hour

and, hey, in today's world, who's got the time?

So here's a little trick.

I've got a little technique over here

which is going to breathe this wine

in about 30 seconds.

GLUGGING

'Yep, it's going into a blender.'

The theory is this -

that by allowing wine to breathe,

oxygen in the air reacts with tannins -

bitter chemicals from the skin and seeds,

altering them so they no longer taste so strong.

Well, I'm going for the same effect using this.

'I'm asking Marcus to compare the taste of wine

'after a few seconds in the blender

'compared to wine straight from the bottle.'

So this is the blended wine.

It changed the wine, there is absolutely no two ways about that.

You aerated it, it mellowed, it's tight and strong.

You've done exactly what you wanted to do.

But I don't like what you did with the bottle of wine.

It is completely the wrong thing to do.

But, surely, taste is all.

Surely, if this works, it doesn't matter what it looks like,

it doesn't matter how it sounds.

What really matters is what it tastes like.

I guarantee you,

you will never ever, ever convince a wine waiter

or anyone that loves wine to do what you just done.

You're not going to be using this technique

-in your restaurants?

-Absolutely not.

-Go on, you can drink yours. Chin-chin.

-Oh, cheers.

That's bizarre.

Thank you very much!

Well, I've managed to impress Marcus

with a couple of pieces of science. First with the chips, and now wine.

But it's time to get back to the main competition.

I'm bobbing and weaving back in the kitchen

and ready to take the fight to Marcus.

This time, the challenge is who can make the smoothest,

most delicious mashed potato known to man.

First, we must choose our weapons.

I'm using Yukon Gold potatoes, so a waxy potato.

And I'm going to bake them in the oven.

-OK, yep. And then scoop them out the skin?

-Yep.

-OK.

I'm going to be using a little new potato,

a Ratte potato, a waxy potato, and it's got a lovely texture to it.

It's not too wet, and I'm going to steam mine...in the skins.

'OK, game on.

'Now, the problem with potatoes is that, on their own,

'they're just dry and claggy.

'I know what Marcus is going to do,

'but do we really need to add oodles of butter?

'I'm going to make a velvety smooth mash using no dairy at all.

'And I'm going to do it by breaking

'the potatoes down at a molecular level.'

These are delicious potatoes, but one of the problems

is that the starch in them

is in the form of granules, and in order to get that velvety taste

in the mouth, we need to break those granules down.

This is a picture of the cells of the potato

you're now peeling, and very similar to this.

So those things that look like stones are the cells,

the potato cells, and inside those are the granules of starch -

those red blobs.

And they're quite big, they can be almost a tenth of a millimetre

and I'm guessing the way that you're going to do it,

you've got the same problem, is by pushing it through a sieve first,

and then probably, maybe, another sieve and another sieve.

That's right. How do you get round that?

-We're going to have to snip them up molecularly.

-What?

-Yeah.

In snipping them up, we're going to get a velvety, ultra-smooth puree.

I don't understand when you start talking about potatoes

and you say you're going to "snip them up".

We're not snipping THEM up, we're snipping the starch granules up.

And this is the magic ingredient over here,

-it's called diastatic malt powder.

-Oh, no...

Like all these things, I've got to get it exactly right.

-Course you have!

-It can go too far.

We don't want to snip it to the point where it's a liquid.

'The diastatic malt powder

'is mixed with the potato, ready to be cooked

'sous-vide in the water bath.'

Mashed potato in the making.

Into the water bath for ten minutes.

-What temperature?

-52 degrees.

So that temperature is the optimum temperature for the enzyme

to start working at these granules of starch and breaking them down.

Right now, inside the water bath,

something astonishing is taking place.

At precisely 52 degrees,

an enzyme in the powder has been activated...

..which is speeding up the way starch molecules fall apart.

But unless it's deactivated in a short while,

it could turn my potatoes into mush.

'Meanwhile, over there,

'Marcus and Jane are having to force their potatoes

'through sieve after sieve,

'trying to squeeze every last lump

'into submission.

'That's an awful lot of elbow grease.'

So this process in my kitchen is...

My chefs do it every day and they find it incredibly painful.

Because it's hard work.

On the other hand, on our side of the table,

we're relaxing! The water bath and this malt powder's

doing all the hard work for us, snipping away.

It's like going to the gym, Mark,

the pain of it you don't like.

But, God, the results at the end can look good.

-This is going to taste good.

-OK.

So you're doing what? You're taking it out of your bag?

Yeah, now we've got to deactivate the enzyme

by taking it up to 75 degrees centigrade.

That will stop the pureeing process at the molecular level

and then it's all about just...you know,

serving it up, really.

I would love now, I really would love

to be sitting at home watching my father's face

when someone like you says, "I'm going to deactivate the potato."

He's just not, you know...

He's just not going to comprehend what you're talking about.

Mark, it's a spud.

It's a spud, it's one of the best vegetables around, isn't it?

'But I am getting a little worried.

'In principle, my mash will be velvety smooth and slightly sweet,

'but taking all the butter and cream out is a big ask.

-How is it? What are you thinking, Antony?

-I'm a bit...

I'm talking to Antony.

What do you think, Antony? Is he talking rubbish?

Come on, talk to a chef.

-Antony, tell me. And, Antony, don't lie to me.

-OK.

-What you going to do?

-I'm going to tell him the truth.

-Yeah, OK.

-It's delicious.

'Oh, it sounds like Antony might be putting on a brave face.

'And Marcus, he's just baiting me with his butter.'

Are you sure you don't want any of this?

-My goodness me.

-Oh!

'And he's not finished, there's more going in.

'A mountain of butter to seduce his customers.'

We just want to give them really good-tasting food. .Thank you.

But they want to taste the potato, don't they?

They do, and do you know, to be fair,

even though I've poured a packet of butter into this, almost,

and half a pint of milk and I'm going to add some cream into it

and lots of salt. It still tastes like a potato.

-It does.

-This is done.

Isn't it?

Antony suddenly doesn't look so sure!

Antony, what do you think?

It needs a bit of a...whisk.

But the potato flavour's there.

'I'm beginning to feel a little queasy.

'Marcus is almost ready.'

-Right, you ready?

-It's the best we're going to get, I think.

Don't say, "Best we're going to get"!

I'm ready, OK, yeah.

'Here goes with my mash.'

Beat that, Marcus Wareing.

Wow.

No dairy at all, no milk,

no butter, no cream,

but look how creamy this is.

'I'm just trying to convince myself.'

-Are you ready? Yeah.

-ANTONY GROANS

Wow.

Do you know what, Mark?

I know for a fact I've won this one

and I haven't even tasted it yet.

MARK LAUGHS UNCOMFORTABLY

That's heresy from your lips!

The taste is all!

Yours does look better, I agree with you. But does it taste better?

-Which would you rather eat?

-We do eat with our eyes.

Yeah, we do eat with our eyes, yeah.

-So which would you rather eat first?

-Well...

-Tell the truth, come on.

-They both look interesting to me.

A couple of sausages nearby, you know, I'd be in there.

Exactly. Home-made.

Yeah, that's true, it has a more of a rustic feel, more of a...

I tell you what, does feel like,

-when you go into it, it feels really soft.

-Yeah.

Oh, my God.

You're kidding me?

Can I try?

Oh, yes.

You're serious?

It... It's potato-y.

No, it's not.

Do you know what comes out first?

-Sweet.

-That is sweet.

'Hmm, I knew the starch granules would break down into glucose,

'which is a kind of sugar, so I was expecting it to be a bit sweet.

'What I got was sweeter than a sugar boat sailing on a sea of honey.

'And my super-smooth texture is just gloop.

'But science is all about experimentation.

'Things went wrong this time, but tomorrow I'll start afresh.

'Right now, though, I'm just going to have to face the music.'

I can't taste potato.

You've completely ruined

those beautiful five potatoes you had earlier.

It's so unfair, you know what you should do now? You should apologise.

-Go on.

-Obviously, this is work in progress.

-You're not going to convince me, Mark.

-Yeah.

Is there anything about this,

-anything at all...

-No.

-..of merit?

-No.

No. Nothing. You've ruined it.

It doesn't work, it's disgusting.

-It's disgusting!

-You should be ashamed.

HE LAUGHS

-Must try harder.

-"Must try harder."

-Yeah, you know, I take it, I'll take it.

-Are you going to apologise?

-Don't apologise.

-I am very sorry, potato.

I can sleep at night now.

That's not good, that's not good.

Right, I'm going to ask someone else now.

-It's work in progress.

-Antony...

-Oh, it's disgusting.

-..you've been standing there... Thank you.

-It's disgusting.

Do you know what, I've had sleepless nights over this!

THEY LAUGH

'OK, so he's got me on the ropes and I'm three rounds down.

'At least I showed him what I can do with a potato with my chips.

'And there's still one round to go.

'The hardest dish on our menu.

'Dessert.

'My last chance to land a knockout punch.'

But before that,

we know that our sense of smell -

and even how we see things -

can affect how food and drink tastes.

Now, I want to try something out on Marcus

which is even more extraordinary.

At the forefront of science is a radical new idea.

That what we hear can also affect what we taste.

Small piece of chocolate.

Just let it melt in your mouth and I'll play this sound.

HIGH-PITCHED, NEW AGE STRUMMING

'OK, so this sound is kind of high-pitched.'

OK, now I'm going to give you another piece of music

and the same chocolate. Goes in. OK.

DEEP BASS TONE THROBS

'This one has a lower pitch.'

'Does Marcus notice any difference in the taste of the chocolate?'

What do you think?

HE SIGHS

It did taste different.

-The second noise.

-That's the low noise.

The lower note felt like it dulled the flavour down,

it wasn't as sharp, it wasn't as fresh.

Astonishingly, it appears that our sense of taste isn't fixed -

it's flexible - and what we think of as one flavour

can actually change depending on what we're listening to.

Quite a lot of people get this effect

where the higher notes are associated with sweeter flavours,

the lower notes with the kind of bitter, lower...

But is that your mind telling you, or is it really happening?

Our senses, the hearing, the taste, the smell,

all come into the brain,

but they sometimes sort of cross over and what you can hear

can actually affect the taste,

because the wiring in the brain is not...

They're not completely independent of each other.

-That is a fascinating experiment.

-It really is amazing, isn't it?

That is the first thing I'll wake up tomorrow morning thinking about.

I want to show you what's behind these locked doors

because it's really exciting.

It's a room full of cacao beans.

These are from Venezuela,

these are from Peru,

and this is what they look like.

Actually, they look a bit odd,

a bit unprepossessing.

They don't taste of chocolate at all,

sort of a bit nutty...

Actually, remarkably plain, and that is the odd thing.

How... How does something like this

get turned into my favourite indulgence, chocolate?

'Chocolate may be a familiar flavour,

'but turning the humble cacao bean into the chocolate that we love

'is a complex process perfected over centuries of experimentation.

'Luckily, I'm in the right place

'to find out how this magical transformation is performed.

'Willie Harcourt-Cooze is one of only a handful of small-scale

'chocolatiers who make chocolate from bean to bar in the UK.

'And he's going to show me how it's done.'

-This is the chocolate factory.

-Lovely.

'Like his namesake, Mr Wonka,

'Willie has got all the gizmos.

'First, you've got to roast your raw bean.'

This is the first step of the chocolatier.

And it's basically the roasting of the bean.

I mean, it's a giant step,

I want to say for mankind,

but a giant step for the cocoa bean, really.

And if you try it now,

it's got a very different flavour than five minutes ago.

It's slightly crunchy. Some of that acidity's been driven off.

So, important you roast them properly.

'Then remove the shells.'

Smell that.

That is a completely different aroma, you know?

-It's completely different, yeah.

-Now we're getting somewhere.

-Next stage.

'Now things start to get interesting.'

Now, we're going to release all of these flavours.

I'm definitely up for that.

The back roll goes really slowly,

the next one goes a little bit faster, it picks it up,

and it rolls it between the two rollers to refine it.

And then it's coming out here,

and if you were to have a little try of that...

Oh, that's good. That is lovely.

There's a lot of flavour. There's a lot of flavours going on in there.

'That's better.

'This is chocolate in its purest form.'

This is like your roasted, shelled,

ground, refined, pure mass cacao mass.

When we take it to the next stage and re-warm it,

it will just turn into a sea of chocolate.

Oh, wow! OK, OK...

'To turn it into a shiny chocolate bar

'requires two more ingredients and, crucially,

'an amazing piece of chemistry.'

-What on earth is this?

-My favourite machine.

'In the wonderfully named conching machine.

'The chocolate is aerated to help develop flavour.

'The smooth texture comes from added cocoa butter

'and it's made sweet with sugar.

'But here comes the special part.'

So, spread this out.

'The fat inside chocolate is polymorphic,

'which means it can exist in different crystal forms

'but, crucially, one of the crystals has superior taste and texture -

'the one known as Type V".

'And by manipulating the chocolate

'while carefully controlling temperature

'in a process known as tempering,

'Willie can promote the formation of these particular crystals.'

What you're trying to do here is try and create Type V crystals

-by having it cooling on this marble, is that right?

-That's right.