Original subtitles

[music playing]

We drink more than seven and a half billion pints

of beer a year.

That's more than 20 million every day.

No wonder is the nation's favorite alcoholic drink.

Whether you're making craft ales, stout, or lager,

brewing is a complex process that involves malting,

mashing, and fermenting.

It's all happening in here at Britain's biggest brewery.

I'm Gregg Wallace.

I've never seen anything like this.

The scale of this production is so ginormous.

And I'll be following the incredible journey lager

takes from barley to beverage.

One small step for mankind, a very long way

for a pint of beer.

[music playing]

I'm Cherry Healey.

Oh, wow.

And I'll be discovering the secrets of the perfect pint.

You can really smell the alcohol, actually.

GREGG WALLACE: Historian Ruth Goodman--

Gosh, that is dark.

GREGG WALLACE: --discovers how beer got its stereotypically

blokey reputation.

Men get interested in brewing when

it gets a bit more lucrative.

Yes.

[laughs]

Over the next 24 hours, three million pints of beer

will roll off the end of this production line.

That is a big night by anyone's standards.

Welcome to Inside the Factory.

[music playing]

This is the Molson Coors Brewery in Burton upon Trent.

They've been making beer on this site since 1777.

And today, they knock out six different varieties.

Tonight, we follow the production

of their biggest seller, which is also the Uk's

most popular lager, Carling.

But no matter what kind you're making,

all beers are traditionally made from just four key ingredients,

water, hops, yeast, and barley.

This humble grain is essential, providing the nutrients that

kick start the brewing process.

[music playing]

From the farm the raw, barley heads 56 miles north to Burton

upon Trent.

But it can't go straight to the brewery.

Before it can be used to make beer,

its internal chemistry has to be altered.

And that happens here at Shobnall Maltings.

The operation is overseen by production

manager, Mark Warren.

Gregg, pleased to meet you.

Nice to meet you.

I've come to see the barley unloaded.

Our beer production begins.

With only four main ingredients, you

might think this would be a quick process,

but you'd be wrong.

It'll take nearly two weeks to turn this lot into beer.

[music playing]

Is he dumping it into the floor?

Into this pit, there's an elevator there, up through the

building, and over into a silo.

Wow.

[music playing]

In just 30 minutes, this clever, subterranean system transports

all the barley to the silos.

[music playing]

How do you turn this into beer?

What has barley got that makes beer?

What that is is a food package full of starch.

All we're going to do is break down the cell walls that hold

that starch together, that allows it then to be converted

into sugars at the brewery.

GREGG WALLACE: It's these sugars that will give

us our all important alcohol.

What's that process called?

Molting.

Is there a traditional way?

Is that the way we've always done it?

Since Egyptian times.

Is this molting a long process?

I'm afraid so, yes.

Are you happy to show me how it's done?

I certainly am.

Well--

Let's go way.

Thank you very much.

[music playing]

Over 40 tons of barley is piped from the silos into one of 10

giant containers, called steeping vessels.

This is the start of the molting process.

GREGG WALLACE: The barley is submerged in 138,000

liters of oxygenated water.

What we're basically doing is tricking

the barley into growing.

We're doing what happens in nature, in the ground.

So we're giving it moisture and air.

This is a seed?

Yes.

Are you trying to get the seed to grow?

Yes.

And you're going to trick it into thinking

it's falling into the ground?

Yeah.

Right.

OK.

[music playing]

The confused seeds absorb the water.

And after more than 40 hours soaking in this bath,

they've tripled their moisture content.

Oh, I thought that would be a mush.

No.

I thought that would be a complete mush.

It's not.

So now, that's what we call a chit a chit.

And that is where the rootlets would form.

That little white root that's coming out of there.

That's right.

Yeah.

That's the seed growing?

Yeah.

GREGG WALLACE: This growth is triggered by the release

of starch inside the seed.

So this is a little self-contained living organism?

Yes.

And what is making that root grow is the energy

that's coming from the starch?

That's right.

Wow.

Well, listen, I was never very good at science at school.

Well, I didn't go to school much.

But I understand this perfectly.

[music playing]

Each grain of barley is changing its internal chemistry.

But they're in no hurry.

We're already nearly two days into production.

[music playing]

Luckily, this next stage is a no-brainer.

Just like when you're planting seeds,

once they've had a good water, next they need warmth.

And that's supplied in these mysterious looking buildings,

called germination tanks.

[music playing]

There are four of them here.

And they're all controlled from this room.

Bit of a cool retro tech.

Very important retro tech though.

[music playing]

GREGG WALLACE: Each of these tanks

contains 330 tons of chitted grain.

Oh.

Oh.

What is this?

What is this?

This is germination.

Germination.

This looks like a cross between sand dunes and a baker's bun.

At least, it's warm in here.

It's humid in here.

This is the perfect conditions to grow the grain.

[music playing]

GREGG WALLACE: Giant fans blow humid air at 16 degrees

Celsius up through the grain bed.

How deep is this?

This is about 1.8 meters.

If I tread on there, do we just, like, sink to the bottom?

No, we don't.

Come on, I'll show you.

[music playing]

Hmm, I think I might let Mark go first.

[music playing]

Seems safe enough.

Oh, wow.

It's not like walking on the beach

because the beach is firmer.

I am actually sinking.

My feet are sinking in there.

It's safe, right?

It's perfectly safe.

It's really, really soft.

One small step for mankind, a very long way

for a pint of beer.

Oh, I really love this.

[music playing]

Inside the grain, the chemical transformation

is almost complete.

How do you know it's ready?

We look at two things.

One is what we call the [inaudible] which

will become the stem of the plant, which

is growing up inside the grain.

So we split it open and look there.

And then secondly, I just rub running through my fingers.

It's definitely squishy.

I feel you can feel the starch.

It's powdery and sticky.

That's right.

How long does it stay in here for?

Four days.

This is not a fast process, is it?

No.

It really isn't.

But this is now ready to be made into beer?

No, we've got one final stage for that.

[music playing]

GREGG WALLACE: The starch in the barley is now unlocked.

And to stop the seeds eating it all up before it

can be used to make beer, we have to halt

the germination process.

Nearly six days after it arrived,

the barley is dried in this massive kiln for 21 hours.

[music playing]

So this is it.

This is our finished product.

This is malted barley.

We took barley in at the start.

This is now malted barley for the brewery.

GREGG WALLACE: It pours through a grate into the back

of a lorry which is driven backwards and forwards

to ensure even distribution.

[music playing]

It doesn't look a great deal different

than it's looked throughout the rest of the process.

It doesn't.

And I have a sample here.

It smells malty though.

That's right.

It smells malty.

You can now eat this.

- Can you? - Yeah.

And it's [inaudible] nice.

Oh, let's cover them in chocolate.

Has anyone thought about that?

[music playing]

Is that it now?

Is that ready to be made into a lager?

It is.

You can go and make it your beer with that now.

Well, thank you very much indeed.

It's was a pleasure.

[music playing]

GREGG WALLACE: My 27 tons of malted barley

has covered the one-mile journey from the maltings

to the brewery.

This place is colossal.

Spanning 120 acres, this huge site is over half a mile

across.

At the intake area, six lorry loads of malted barley

arrive every day.

Brewing manager Andy Runsey is waiting for.

- Are you Andy? - Hi, Gregg.

How are you?

I'm good, mate.

All right.

I've got a trunk of malted barley here.

What do I do with it?

You leave that there.

They all get offloaded here.

And we all go make some beer.

That is a good idea.

Show me where to go.

My malt is unloaded and a system of conveyors

transports it 30 meters to the top of the six-story brewhouse.

We've got to go up there?

Yeah, all the way up the top.

Why did you need to brew beer in a tower?

Historically, all brewhouses were built in a tower

because you could get to pump it up once.

And then gravity does all the hard work after that.

Come on, I hope you're fit and well like me.

[music playing]

GREGG WALLACE: By harnessing the power of gravity,

instead of using pumps, the brewery

can save energy and money.

Mate, this is a bit much, isn't it?

[music playing]

At the top, the malted barley arrives at the hammer mill.

At last, I've climbed a mountain of stairs.

Is this beer making?

This is starting to make beer, Gregg.

Right. OK.

So apart from being hot and noisy, what is it doing?

This is taking the malted barley

that you brought from the maltings

and turn it into this fine powder.

We call it grist.

It looks like baking powder.

Inside the mill, 128 little hammers, called flails,

spin at 1,500 RPM.

As the malted barley drops down, it's

smashed against these hammers, crushing

each grain into tiny particles, most

less than a millimeter across.

This ferocious contraption crushes nearly

four kilograms every second.

That means that in just one hour,

it produces enough ground barley to make 224,000 pints.

The grist drops down into imaginatively named grist cases

on its way to the mash vessels, where the brewing

process begins in earnest.

Oh, that's like R2-D2's head.

That's the mash vessel.

Well, that's just a big empty tank.

That's because we need to mash in.

Mash in.

Yeah.

Mash in.

In order to mash in, we need some help

from the control room.

Andy is letting me do the honors.

OK to mash in.

Over.

Yeah, OK.

Yeah, agreed.

He reckons that's one of the best mash in messages

he's ever had [inaudible].

11 tons of grist are released into the mash vessel,

followed by 26,000 liters of water,

heated to precisely 66.5 degrees Celsius.

The combination of water and heat

helped start a chemical reaction, which

causes the starch molecules in the grist

to break down into sugars.

It's this sugar that will ultimately turn into alcohol.

But we're way off that yet.

That grist is coming out with the water.

It's like creamy color.

Yes.

Well, actually, it's poppy colored.

That is an enormous great latte.

Yeah, it's a very thin mash.

So tell me, please, what is happening?

Why hot water?

By using that temperature, we get as much sugar as we need,

but we leave a little bit left over to get a little bit

of sweetness in the final beer.

And this is the famous Burton water, right?

Perfect for making beer.

Yeah.

This is what the town was built on.

But now, because of modern standards,

we need to purify that water first.

I thought it was perfect for making beer.

It was when it first started, but, obviously, standards

change.

All right.

So now we're purify it and add back in what we need.

So 150 years ago, you could just

- draw the water from the well. - Yeah.

Different health and safety laws now.

Yes

How long does this take?

It takes an hour and 50 minutes.

Right.

But there's one over there, if you have a look at that.

You're getting the hang of this telly lark, isn't you?

I'm starting to get there.

[music playing]

GREGG WALLACE: It takes just 60 minutes

of heating to extract all that starch and convert it to sugar.

So the mash is finished now.

Now that looks like beer.

It's brown.

And it's got a foamy head.

But that's got no aroma.

No because that's just a sugary liquid at this point.

Right.

So what has it done exactly?

Just got the sugars out.

It's made a nice, sugary liquid for us.

GREGG WALLACE: As I'm discovering,

brewing is a complex process.

Yet, there are only four ingredients

traditionally used to make beer.

Cherry is getting to grips with the recipe.

[music playing]

I've got to admit when I walk into a pub,

the array of beer choices can be a little bit overwhelming.

How can the same basic ingredients

make one beer that looks like this and another beer that

looks like this?

[music playing]

To find out, I'm going to a microbrewery in Walthamstow,

East London, to meet chemical engineer

turned brewer, Jaega Wise.

Hi, Jaega.

Nice to meet you.

Nice to meet you.

What a beautiful spread.

So what do we have here?

We've got porter, an IPA, and a lager.

And they really are at the extremes of what you can

create with four ingredients.

CHERRY HEALEY: Malted barley, hops, yeast, and water

are the basis of all beers.

But subtle differences in these ingredients

have a big impact on taste and appearance.

It all starts with the water.

So where we are in London, the water's very hard naturally.

CHERRY HEALEY: Hard water is ideal for brewing porters

and stouts.

Soft water on the other hand, is better for lighter beers

with more delicate flavors.

One of the most famous places in the world

for very soft water is Pilsen, as in the Czech Republic.

And that's where the pilsner has developed.

CHERRY HEALEY: Today, Jaega isn't using good old London

tap water to make a porter.

What gives a porter that dark color?

It is all about the very, very dark roasted barley.

This is the fundamental difference between a beer

like this and a lager.

We can create chocolate flavors.

We can create coffee flavors, all from the intensity

of the roast.

CHERRY HEALEY: Roasting the barley before brewing

brings out different flavors in the beer.

Oops, just on top of it.

That's it.

Mashing this toasted grain with hot water--

Oh, look at that.

Wow.

- -gives porter its dark color and helps

create those rich stout flavors.

[music playing]

For IPA or lager, like the one Gregg's making,

brewers would use lighter malts.

Now it's time for ingredient number three, hops.

Hop plants are climbing vines that grow up to 10 meters tall

and produce leafy green flowers.

These flowers give beer its aroma and bitterness

and work as a preservative.

Are there more than one variety of hops?

There are a lot of different varieties of hops.

So this one in particular, this one's known as Centennial.

So this is a hop from the US.

You can probably smell.

It's quite pungent.

Very strong.

Yeah.

What is it in the hops that make them perfect for beer?

So the main things we're concerned with,

the alpha acids, the beta acids, and the essential oils.

So the alpha acids is what gives our beer its bitterness.

The beta acids, there's been lots of research showing

that's where beer gets a lot of its stability and

its antibacterial properties.

And your essential oil-- so that lovely citrus note you can

smell, that is what this brew is.

That is what we're after.

CHERRY HEALEY: Porters require very bitter

hop in order to balance out the flavors from the roasted malts.

Hops away.

While lager tends to use more subtle varieties.

The final ingredient is yeast, which

gives us that crucial alcohol.

So if you hop onto the step, we should be able to see

some yeast in action.

All right.

This Porter uses a strain of ale yeast.

Ready?

Yep.

Oh, wow.

You can really smell the alcohol, actually.

What is this bubbly area around here?

So this is actually the yeast sat on top.

And it's how ale yeast likes to behave.

We call it top-fermenting, so it likes to ferment and really

sit on the top, whereas a lager likes to ferment on the bottom.

So we call it bottom-fermenting.

It's one of the major differences between an ale

yeast and a lager yeast.

[music playing]

CHERRY HEALEY: Using different varieties of lager or ale yeast

will bring out different flavors in the beer.

Four ingredients, three very different-looking beers.

Now I get to taste the porter I've been brewing.

[music playing]

You can definitely taste the coffee,

the chocolate, the caramel.

It's more like a meal.

Next the lager.

So it's quite light, but it's quite bitter.

Is that the hops?

Yes.

That's the hops.

Finally, the IPA.

Whoa.

It's citrusy.

Yep.

And hoppy, grassy, bit nutty.

It just shows just how diverse beer can be.

They taste so different.

And yet, they have got the same four ingredients.

Yep.

- Well, well done, Jaega. - Cheers.

Cheers.

[music playing]

GREGG WALLACE: Back at the Burton Brewery,

we're over six days into our beer-production process.

After one hour of heating in the mash vessels,

all the starch in the barley has been converted to sugar.

And Andy and I are in pursuit of hoppiness.

What do you want to do with this?

Weigh myself?

No, I want you to weigh the hops.

Are these hops?

Yeah.

Are they very trendy?

Are they hip hop's?

I thought hops were like buds, a little bit like corn.

Yeah, but a lot of that hop is waste, ultimately.

So what we do is we pelletize them

to get all the bitterness we want, but none of that waste.

Well, we've got an enormous VAT of sweet,

malty liquid at the moment.

Yeah.

How much of these hops do we need to add to that?

We need 21 kilos.

So what do I do? Put the bags on?

Yeah.

- So those are five-kilo bags. - All right.

OK.

Well, look, 5, 10, 15, 20 kilos.

So I've got 20 kilos.

I need another one kilo.

Should we put that bag on?

Yeah.

So another kilo, right?

Astonishingly, this relatively tiny amount

will be enough to flavor over 190,000 pints.

There you go.

Perfect.

Right.

21 kilos.

Where do we go?

We're going to put them in the hopper.

You grab one. I'll grab the other.

- Go. - Here we go.

Yep.

Wait.

[music playing]

It's just a short hop over to the holding tank to unload

our carefully weighed goodies.

[music playing]

Is that it?

No, we need to add some calcium chloride as well.

Calcium chloride?

Yeah.

OK.

Give me that.

What is calcium chloride?

Calcium chloride is just a--

we're just replacing some of those things

that we took out of the water when we purified it earlier on.

Right.

OK.

What does it give you?

That balance of sweetness and bitterness.

Is that right?

Yeah.

GREGG WALLACE: Calcium chloride is a type of salt. Adding

12 and 1/2 kilos of it into the mix,

will help bring out the flavors in the beer.

It's just like adding seasoning to your dinner.

Right.

All the stuff's in there.

What's the next stage?

Before the hops are added, our non-alcoholic, sugary liquid

is sent from the mash vessel to this giant, robotic accordion,

called a mash filter.

Here the mix gets passed through a series of plates which

sieve out the leftover grist.

[music playing]

56,000 liters of the clean, filtered liquid,

now called wort, is then pumped into giant vats,

called coppers.

[music playing]

Yes, I know.

They're clearly not made of copper.

But in the early days of brewing,

they were and the name stuck.

Are the hops in there?

They're not in there yet.

I know how much you like at radio, Gregg.

Do you want to add the hops?

Press the button.

- What do I say this time? - Add the hops.

Is that it?

Yeah.

Yeah, it's Gregg.

Can you add the hops, please?

OK.

GREGG WALLACE: With a little help from our friendly control

room, the hops dropped down into the copper

through a pipe in the ceiling.

So those hops are now dissolving, aren't they?

Is that right?

Yeah, we're going to get the bitterness in those hops.

And we're also going to form some protein

that we can move later on to make a nice, cleaner beer.

GREGG WALLACE: The mix is boiled for 40 minutes.

As well as releasing the hop flavor,

the heat kills off any bacteria in the worts.

This is a really slow process.

When I normally go to factories, they can make crisps

or biscuits in like an hour.

Does this get any faster?

Sadly, no, Gregg.

We can't rush it.

GREGG WALLACE: Today, hops are an essential ingredient

in beer.

But it wasn't always that way.

And as Ruth's finding out, their introduction

changed everything.

[music playing]

RUTH GOODMAN: In the Middle Ages,

the homemade ale Britons enjoyed tasted very

different from modern beers.

It was sweet, unhopped, and brewed

almost exclusively by women.

Brewing was one of the most common professions

for women, who were often known as brewsters or ale wives.

It's believed that a third of women in villages

were brewing ale for sale.

Women learnt the techniques from their mothers and aunts.

It passed down in the female line.

But this dominance was not to last.

[medieval music]

Beer writer Jane Patton--

Hello, Mistress Goodman.

- RUTH GOODMAN: - -tells me the change

began with some early consumer-protection

legislation.

In 1266, King Henry III passed a law

the size of bread and ale.

So he appointed ale-conners.

These were male inspectors who went around all

the places selling ale.

And they would test the quality.

And if they found it to be bad quality,

or if the ale wife was overcharging for that ale,

then they could be punished.

[medieval music]

RUTH GOODMAN: The homes of female brewsters

became known as public houses or pubs.

Ale wives continued to brew on a small scale,

until our game-changing ingredient arrived.

What changed everything was the introduction of hops.

RUTH GOODMAN: Historians think hops

were introduced to Britain from Belgium in the 15th century.

At the time, the unhopped brew made by ale wives

went off within a day or so.

It was soon discovered that hopped beer lasted far longer.

This was a revolution.

And this is where the schism between the male brewers

and the female brewers starts to come in, hops.

RUTH GOODMAN: Hopped Beer could be brewed in bigger batches,

making production more profitable.

Men get interested in brewing when

it gets a bit more lucrative.

Yes.

[laughs]

You could say that.

And also brewing on a big scale in factories,

basically, where women didn't work outside the home normally.

So it's going to be easier for a man to set

up as a commercial brewer.

So this, really, is the great reason for the divide,

for the change, from brewing as a female activity to brewing

as a male activity.

Yes.

And the irony is that these are the female part

of the hop plant.

[laughs] To ale wives.

To ale wives.

[music playing]

GREGG WALLACE: In the brewery, my sweet, malty liquid,

or worts, has been boiling away in the coppers

and is now fully infused with those fragrant hops.

But it's still not beer yet.

To turn this wort into lager, we need yeast.

Whoa.

I'm meeting Steph Tungs in the project lab.

Hello.

Is that dry ice?

This is liquid nitrogen. And it's currently at about

196 degrees below zero.

That's how we store yeast.

And I can't go anywhere near that, can I?

Absolutely not, not with some serious gloves on.

Yeah.

Why do you store the yeast like that, please?

So we keep it in a stable state

to stop it from growing any more than we would need it to

at this time, so we can keep it for long periods

to use it whenever we need.

GREGG WALLACE: Yeast is a living, single-cell organism.

Without it, there's no alcohol, no fizz,

and, ultimately, no lager.

[music playing]

How much yeast is in there right now?

About 0.2 of a milliliter, so a tiny, tiny amount.

Is that just a sample?

No, this will now propagate all of our yeast

for the next six months.

What?

Sorry, didn't mean to shout.

How is that possible?

I thought it was ridiculous, the amount of

hops you were putting in.

Just that little bit there?

Yeah.

That'll keep you going for six months?

Yeah.

It will soon multiply and become everything

that we need within six months, given the right conditions.

GREGG WALLACE: The yeast is grown

in this 30-milliliter vial.

Steph adds worts before mixing it all together.

She then transfers 10 milliliters of the mix

into this flask.

The extracted yeast now has the food

and space it needs to multiply.

Is it extremely valuable?

Absolutely, without our yeast, we just wouldn't

have a brewery to go with.

It's so valuable to us.

It's the life and soul of our beer.

GREGG WALLACE: As it grows, the yeast

is transferred to increasingly larger containers,

finishing up in this massive tank.

It will continue to multiply until they have over 1,000

kilograms of the stuff.

Then the whole lot is sent to the fermentation

tanks which are full to the brim with our sugary worts.

So what's the volume of liquid in there?

There's 2,400 UK bottles in one of those.

GREGG WALLACE: Those of us not in the pub trade,

that's enough to make an unbelievable 1.3 million pints

in just one of these tanks.

And there are 19 of them.

You've got a bottle of brown.

You have not beer yet, you've just had bottles of brown.

Yeah, so this bottle of brown is the last time it's

wort before it becomes beer.

GREGG WALLACE: This sugary liquid

is the final stage of production before fermentation starts.

Can I have a sip of this?

Of course, you can.

Is it going to be horrid?

We'll see.

It's almost sweet like honey.

And it is going bitter.

And it's actually that bitter flavor you get

at the end of a pint of beer.

Yeah.

But it started off like a sugar drink.

Yeah.

GREGG WALLACE: Inside this fermentation tank,

this sugar drink finally becomes beer.

But it doesn't happen quickly.

Over the course of five days, the yeast cells

feast on the sugars and then expel alcohol and carbon

dioxide as waste byproducts.

The CO2 is siphoned off from the top to be reused later.

And once the batch is finished, leftover yeast

is extracted from the bottom.

And has it used up all of the yeast?

The yeast there is topped off and reused.

So we reuse our yeast about eight times.

GREGG WALLACE: After 11 days and 22 hours,

we finally have alcoholic, slightly fizzy beer.

But it's not quite ready to drink.

[music playing]

Andy, what is this?

It's completely like space age.

What does it do?

Don't tell me.

Deep-sea divers have left their tanks here.

No, this is where we filter the beer.

Well, just like a normal filter?

Yeah, so inside these, there are lots of little membranes

that filter out all the particles.

That looks like it's sitting still.

Is that beer flowing through there?

Yeah, in here, it's producing about

2,400 cans of beer a minute.

So it's just gushing through there

faster than my eye can tell.

Yeah.

GREGG WALLACE: This massive system of filters

removes any leftover protein or yeast particles,

leaving clean, but slightly flat, lager.

I've seen hours and hours of beer-making process.

And when I finally get to taste it, it's in a medical jar.

Yeah, it's a sample.

Have you not got like a nice jug with a handle on it?

We don't drink in the brewery, Gregg.

We only sample.

I can taste my hops.

Yeah.

I

I can taste the hops.

I can even taste the sweetness.

That's more like an ale.

To transform it into fizzy lager,

the carbon dioxide given off during fermentation

is pumped back into the liquid through the carbonation

machine.

Our lager now has those all important bubbles.

And at last, I get to try the genuine article.

That tastes like a clean, more fizzy, final lager.

That is the end-finished product.

That's the end-finished product here in brewing.

We now need to put it in a package.

Andy, thank you.

It's been fascinating.

After almost 12 days of production, we've got beer.

But how should we serve it to get the most out of the flavor?

Cherry is investigating.

To pour the perfect pint, you first

tilt the glass to a 45-degree position

until it's halfway full.

And then you straighten up into an upright position.

And now we have a perfect pint.

But, does a great-looking pint make it taste any better?

[music playing]

To find out, I'm meeting sensory scientist

Professor Charles Spence from the University of Oxford.

Surely, it's just about the beer in the glass.

For any one of us it feels like it's

just the liquid in the glass that we're tasting.

But a different glass, a different color,

or a different shape, all these other factors

matter, some more than others.

So exactly the same beer can taste different

under different circumstances?

Absolutely.

And this is the kind of thing that we can test.

I'm pretty sure I can find some volunteers for this.

[music playing]

We've taken over this pub to run three scientific experiments.

In each test, will be serving exactly the same beer.

But we'll change one thing in the way it's served.

First, we present our tasters with a straight glass

and a curved glass.

Take a sip of each beer, maybe two or three.

Take your time.

Which is more flavorful?

Aromatic?

Fruitier?

Mm, interesting.

Yeah, that's definitely more fruity.

I think this one has a little bit

more interesting flavor notes.

I think that one's--

was it fruitier?

Yeah, that one's fruitier, I think.

CHERRY HEALEY: Over half our tasters

think the beer tastes fruitier in the curved pint glass.

So what's going on there?

We find from research with wine, with soft drinks,

with beer, that when you have something more

curved in your hand, that tends to prime notions

of fruity and sweetness.

And you express that in the taste of the beer.

CHERRY HEALEY: This could be one explanation for why people

drink more than twice as fast from a curved glass

compared to a straight glass.

On to test number two.

So here I have two beers, one with a head

and one without a head.

Which is tastier?

This one for me.

That one.

CHERRY HEALEY: The liquid in each glass

is identical, except for the amount of head.

Yeah, I'd say that this one had more flavor.

CHERRY HEALEY: 70% of our beer drinkers

think that the pint with the head tastes better.

That head is capturing all the volatile, aromatic molecules

in the beer.

So when you put it to your lips, you're

getting a bit more release as the bubbles

burst more of the aroma.

And we know that 75% to 95% of what you think you're tasting,

you're really smelling.

So the more bubbles or burst, the more head on the beer,

the more flavorful the pint.

CHERRY HEALEY: In the final test,

our tasters are served a pint at 3 degrees Celsius and another

at 12 degrees.

There's more flavors in that one.

Actually, I have to agree with you.

CHERRY HEALEY: All of our beer drinkers

rated the warmer beer as more flavorsome.

The thing is that our taste buds don't work,

really, when they're too cold.

In fact, you get more flavor from warmer beer

because that allows the taste buds to do their work

and pick up the flavor that's in the drink.

CHERRY HEALEY: Despite the ridicule

we Brits get for our warm beer according to science,

we're onto something.

So there we have it.

The secret to the perfect pint, a lovely curved glass,

a healthy amount of head, and served at 12 degrees Celsius.

[music playing]

GREGG WALLACE: In Burton upon Trent,

I am on the final leg of my beer-making adventure.

It's taken 12 days to get from raw barley to lager.

And only now does the finished product

head to the canning area.

17 lorries arrive here every day,

each one delivering 100,000 empty cans.

I'm meeting Packing Operations Manager Gareth Annabelle.

Gareth?

Oh, yeah.

I think you're my man.

I am.

What is pushing them off the truck?

That vehicle has got what we call a live-bed in it,

so it's got rollers in the truck, which transports

it onto this live-bed as well.

[music playing]

GREGG WALLACE: The cans are hoisted up

to the de-palletizer, where a robotic arm sweeps them

off the pallets one layer at a time.

Over 150 meters of conveyor belts

push the cans around the factory to the cleaner.

I've never seen anything like this.

The scale of this production is enormous.

One of the biggest factories I've seen.

And this, I've never seen anything like that,

a lot of upside-down cans.

Is that magnetic?

That's vacuum that holds the cans up.

GREGG WALLACE: The vacuum holds the cans upside down,

as fans below the conveyor shoot high pressure jets

of purified air up into them.

This removes any trace amounts of dust or contaminants.

After a good clean, the cans end up here, the filler.

This giant, spinning top is turning at over 11

revolutions per minute.

The sheer speed makes it almost impossible to see what's

happening with the naked eye.

But 165 cans are simultaneously being

filled with 440 milliliters each of freshly-brewed lager.

Filling all those cans takes just 5.5 seconds.

Now that is what I call a quick drink.

Where's that splash coming from?

So that's the beer.

Because it's filling at such speed,

we can get foam on the top of the beer.

And that foam has got little bubbles of oxygen in it.

Oxygen will spoil the flavor of the beer.

So we have to blow that foam off the top of the can

before we put the end on.

That's why you get little splashes

of beer foam coming out.

Right.

OK.

So once the beer is in, we move through to what's

called the seamer.

- Seamer? - Seamer.

Yep.

And the lid gets put on the can.

The seaming actually happens in this machine here.

It's all enclosed.

But the lid goes on the can.

As the can spins around, the seam

is formed where the can ends.

So once it comes out, it is one piece of equipment.

GREGG WALLACE: I've got it.

[music playing]

Up to 1,850 cans a minute are filled and sealed here.

The operation runs 24 hours a day.

And this is only one of three identical production lines.

In a year, a staggering 350 million cans of our lager

will roll off this line.

And every single one of them passes

through this giant pasteurizer, which

heats the cans for 15 minutes.

This kills off any microorganisms

which might be present, giving the beer a shelf

life of up to nine months.

Then they get boxed up and slid onto pallets,

before being loaded onto an army of waiting trucks.

How many lorries go out?

We do about roughly three or four an hour.

- Really? - Yeah.

But not 24 hours?

24 hours, each of these has got 22 pallets on.

GREGG WALLACE: Just 60 minutes after an empty can arrives,

it's been filled, boxed up, and loaded back on the truck.

Have you got storage area anywhere?

We don't have any storage on site?

No.

Everything that comes in, comes straight out on the vehicle,

and away it goes.

The beer making itself was far slower than I ever imagined.

But this canning is the fastest thing I think I've ever seen.

Unbelievable.

Unbelievable.

I always knew we loved our beer, but this place

has completely blown me away.

From here, the lager is shipped out to all corners of the UK

and Ireland, from Cork to Cornwall, and all the way up

to Inverness.

I am really impressed by the scale of production here.

It is absolutely immense.

But you know what I really like?

Is how long it takes to actually make a pint of beer, over 12

days from barley to can.

And you know, in this 100-mile-an-hour world,

some things just take time.