How do you get 1,000 Yorkshire puddings to rise every minute?
Lots of beating. When they're not quite done, whisk them out.
There's nothing more British than a roast dinner,
and you can buy everything you need for it from the supermarket.
But how is science giving our traditional roast a modern makeover?
How do you reckon this helps with your Sunday roast?
It's like a stretcher. Carrying the potatoes? It's a mystery, isn't it?
How do you get the caffeine out of these beans? Someone steps on them?
Gas it out or something. I think it's dried.
I'm going to reveal the secrets behind supermarket food
by making a roast dinner, food factory style.
Very few of us get the chance to go inside a food factory to see what they're doing to our food.
So I'm going to go back to basics, and in this barn I'm setting up
my own supermarket production line to show you how it's done.
It may look as though it's full of junk, but in here
there's everything I need to unlock the secrets of supermarket food.
Sunday lunch can be a real family occasion.
There's nothing nicer
than a good bit of roast meat with all the trimmings, with everyone round the table to enjoy it.
It's as British as a rainy bank holiday and I love it. There we go.
I'm going to find out what the supermarkets have to do
to put our roast on our tables and the perfect Yorkshire puddings.
But first, I'm going to start with one of the staples - potatoes.
How many potatoes do you think the average person eats in a year?
I think maybe the one that's the fullest. That one. That one.
I would say this one. No. Little one.
The amount of potato one person gets through in a year is quite surprising.
All of these maybe.
Really? Well done.
In fact it's a 100 kilos worth. I can't believe that.
Wow! You're the first person to get it right.
That's a lot of spuds, but even more surprising is that half of that is made up of processed potatoes.
Frozen chips, crisps and this stuff - instant mash.
Now, you might say you don't touch instant mash because it's for lazy people,
but it's really popular and you'll find it being served up in all sorts of places.
If you think about it, instant mash is pretty impressive.
It only takes ten seconds to make, which is madness.
What other hot food can you say that about?
But what have they done to the humble potato to turn it into instant mash?
To find out, I'm going to make my own.
Sadly, it involves chopping spuds.
This is one of my least favourite jobs.
There's got to be a quicker way.
Instead of using one knife, I could bolt a whole load together.
Chop, chop!
Right. With my big, scary, medieval chopper,
I'm going to hopefully turn this potato into slices.
It's got stuck.
With the knives being so deep, the slices can't escape out the top.
A design flaw, I think.
All that work and it's a little bit disappointing.
Well, look - three bits of potato. So much for mass production.
Back to the chopping board.
And now the next step is to blitz my spuds in a liquidiser.
When you blend a potato up, you can see how much moisture is in there.
And there's quite a lot.
It's about 80% water. But I'm making dried instant mash,
so water is the last thing I need.
Right, if I put my potato pulp in the oven,
the heat should evaporate all the water, and I should be left with dry potato powder.
Right, it's been about an hour.
Let's see how it's getting on.
Look at that.
It's hard to believe that that was potato.
Look...how crispy it is.
Having taken the water out, what'll happen when I put it back in again?
Will I have instant mash or instant mush?
It's looking more and more repulsive.
This is something I would probably use to put up my wallpaper with
because it is looking like wallpaper paste.
Doesn't look brilliant, but it's made out of potato, so it shouldn't taste too bad...
That tastes as bad as it looks.
That's rank.
The reason why my potato paste tastes so bad is down to starch.
Now, I've got a slice of potato under this microscope and you can see under magnification
these tiny, tiny grains of starch here that have been dyed purple.
And around them, that's the cell wall.
Now if we have a look at my terrible mashy creation that I made earlier...it's a bit of a mess.
What's missing are the cell walls.
That's because they were ripped apart when I liquidised my potatoes.
The starch grains inside have spilled out
and when starch mixes with water, it turns into a gloopy paste.
Not very appetising.
Gloopy starch was a problem for the early mash makers
until some clever clogs had a weird and wonderful idea.
The 1950s potato scientists cooked their potatoes twice,
and even more strangely, they started with water that was nowhere near boiling point.
I'm cooking mine at 60 degrees centigrade.
That's hot enough to soften the starch grains inside the potato cells,
but not so hot that the cells rupture and the starch gets out.
Everything I'm doing is geared towards keeping the starch firmly locked inside the potato cells.
Right, my potato slices have been in for about 20 minutes.
So what I'm going to do now...
is dunk them into some ice cold water.
Now if you did this at home,
your family would think you'd gone mad.
The icy water stops the starch inside the cells from overcooking and it helps strengthen the cell walls.
It'd be like having a really nice hot bath and then jumping into a barrel full of ice.
Right. Let's get these guys out of the ice cold water...
Now, let's have a look at one.
See they're still nice and firm, but look at that.
Now hopefully, inside the potato, the cells are still all intact.
They haven't bust open, which means all the starch is still inside.
But they're nowhere near done yet.
Well, that first cook was a bit wishy-washy. Time to crank things up.
I reckon this'll do the job.
It's an industrial cleaner.
Just like the factory, I'm going to do my final bit of cooking with steam.
This is usually used for cleaning grease off of industrial machinery, not cooking potatoes!
Steaming is much gentler than boiling.
The last thing I want to do is to bash my spuds and let the starch escape.
You kind of feel sorry for them. They've had a nice warm bath,
they've been dunked in freezing cold ice water, and now I'm steaming them.
You wait till I tell them I'm going to mash them.
Later, I'll find out if steam cleaning has done the job,
or whether I've overcooked it and it'll be wallpaper paste for lunch.
Lamb is one of our favourite roast dinners. The industry is worth nearly £1 billion a year.
Now, we like our lamb lean and tasty, and to make sure it is, the planning starts way before the lambs are born.
David Smith breeds Hampshire Down sheep.
Every year, he has to decide which of his rams will father the best lambs.
Only the biggest and tastiest lamb chops will do for the supermarkets.
Now, these are terrific-looking animals. Really handsome.
What are you looking for when you're choosing a breeding ram?
Well, if just relying on eye, I'd be looking at the loin here,
the giggets or legs here, and just the overall shape.
Each ram can father over 500 lambs in his life time.
So if you want good lamb chops, it's important to pick the best ones.
David rears sheep and I'm a pig farmer, so we should know good breeding stock when we see it.
I wonder if David's up for a little wager?
Now, if you were a farmer, coming to buy a breeding ram out of this lot here,
which one would you put your money on?
Well, the one that I like is number 47.
OK. Well I'll chose one then.
I'll have that one - number 16. You want to put money on it?
OK. All right. I'm not so sure!
Betting on the best ram is a bit of fun, but the supermarkets aren't keen on guesswork.
So David has called in some extra help.
CASUALTY THEME TUNE
Crikey. High tech or what?
This X-ray machine is the same kind of CT scanner you'd find in a hospital.
From the images it produces, Dr Jenny MacFarlane can tell
which of David's rams are best for breeding.
With this machine we can put the whole sheep through
so we can see exactly how much meat is on that whole sheep and the shapes of each muscle.
One by one, all David's rams are sedated and strapped into a cradle.
Hello, mate. All right?
Then it's off to the scanner. I feel like I'm on ER.
It takes just three minutes to reveal the secrets underneath all that wool.
He's quite happy, isn't he, really? Yeah, he's fine.
I feel like I should put some earphones in and listen to music, or read a book!
# Who's afraid of The big, bad wolf... #
He can always count sheep, can't he?
What are we looking for?
In the hind leg we're looking at big leg muscles.
That's where your leg of lamb joint you see in the supermarket comes from.
And people always go for the bigger leg, so on here you're hoping to see nice big... Nice big muscles, yeah.
The leg muscles are this light grey area.
This ram looks pretty meaty to me.
So the second position is through the fifth vertebrae of his spine.
So that's about here? Yes. So sort of your lower back area.
So on there what are we looking for here? That's where we get the chops.
By scanning all his rams,
David can see which ones will father the best lambs.
Now as a ram breeder,
you can actually see inside your animal. Usually you just look on the outside.
Yeah. Here for the first time
we're able to look inside and see exactly how much muscle, fat and bone there is.
It's incredible to see his chops on the telly, isn't it? Mm, it is!
I bet David that I could tell which of his rams is best for breeding just by looking.
You're going to go back. Off you go.
I chose ram number 16.
David went for 47.
Which one of us got it right?
Kirsty, have you got the results?
Which ram is the best one out of this group? Well, from looking at the images...
..I reckon number 47 would be my choice.
47. I think that's the one you said, isn't it? Yes.
So a lot of experience and you've still got it in the eye.
You don't need glasses, so that's fantastic, isn't it?
But what about number 16? That was the next one down.
Thank you. Was that your choice? Yeah.
David was right, and now he can prove to the supermarkets just how good his rams are.
As a farmer, I've seen a lot of things,
but never a sheep in a CT scanner.
Who would've thought high tech hospital kit would be helping us cook up our Sunday roast?
Back in the barn, I'm trying to make supermarket instant mash from scratch.
They're going to be the cleanest potatoes alive.
I've been steam cooking my potatoes, but have I overdone it?
There we go. I reckon they're just about done now.
Let's have a look.
Oh, yes! Still a bit hot, but look at that.
They're just breaking apart in my hands and if you look inside they're still fluffy.
Now I've got to mash them,
but I've got to do it in a way that won't break up the cells
because I don't want all that starch coming out.
Right...
Check this out. This is my monster masher.
In the factory, they do their mashing gently so the starch stays locked up inside the cells.
Not sure which is getting the biggest mashing.
The potato or the masher.
Ooh! I might have a monster masher, but I need to go easy on my spuds.
There we go. I've got some lovely mashed potato
and it doesn't look anything like wallpaper paste.
Best of all, it's nice and fluffy.
The next job is to turn my fluffy mash into dried potato flakes.
Right. Time to put it all together.
To do that, I need to build a device called a drum dryer.
It's what the mash factories use.
So here's the idea. I switch on my drill...
and that spins the drum via this bicycle chain.
I'm going to put my mash on the outside and the water evaporates from it.
But to make that happen, I need some heat.
Perfect.
You can see how hot it's getting here. Look at that!
I've got to spread it nice and thin as I go.
I want it to heat up nice and evenly.
But that's not what's happening. My drum dryer is hot at one end and cool at the other.
You see down this end where it's really hot, it's all really burning, going black.
This end here, a bit cooler,
I've managed to build up quite a layer of mashed potato here.
It's not going black. It seems to be drying out.
So I reckon I should be able to harvest quite a lot of flakes off this.
It's incredible the lengths food factories go to so we don't have to boil a few spuds.
I really want to try and avoid this brown stuff. What I'm after
is this lighter, white stuff here.
It's like picking a good scab.
Crushed up all my little flakes.
Now the big test. Will it turn to mash when I put hot water in?
Right. Lots of effort.
This is coming together and it's smelling very potato-y.
It's definitely better than the first attempt, but you know what?
I'm not sure it would pass for mash.
I suppose if you called it "rustic mash" it might.
Right, taste...
It's a bit like...
It's a bit like porridge.
In that it's lumpy and sticky with a dirty potato taste.
It's not really what I'd call mash.
Oh, no. No, that's not right at all.
In the factory, a thin layer of mash is on the drum dryer for less than a minute.
My thick mash was on there for a lot longer and got burned.
This damaged the cells so the starch escaped.
The result - a foul-tasting gloopy mess.
So I reckon to produce mash you can make in ten seconds,
you need better kit than I've got.
I think the hardest part of the roast dinner to get right are the Yorkshire puddings.
When you cook them yourself,
they can often turn out looking a bit like this, all caved in and a bit unappetising, really.
But when you buy them from the supermarket, they always turn out looking perfect.
So what's their secret?
I've come to Yorkshire to ask the locals what they think works best.
You'd have to ask my mum.
Hot oil. Hot oil? And a hot oven.
My mother used to say at Christmas you need to put the mix outside
and get a snowflake in it and that makes the perfect Yorkshire pudding.
If you think it's tough getting your puds to rise, try coping with 30 million every week.
Welcome to the world of Yorkshireman Stuart Drysdale.
You must feel like you've got the weight of Yorkshire on your shoulders
because you can't mess up Yorkshire puddings, being in Yorkshire, can you?
No, it's our job to make sure every pudding rises and every pudding is consistently perfect.
Just like your puds at home, the main ingredients are flour and eggs.
But Stuart's got a few tricks up his sleeve.
Our eggs are a unique recipe
and we don't have a standard ratio of whites and yolk.
So you don't add an egg by cracking it and putting the whole egg in?
You can put a bit more yolk or white in. We can play tunes with the recipe.
Can you tell me what that special blend is? That's a trade secret, I'm afraid!
He uses wheat flour that's stretchy, so the puds can rise but it's strong enough to stop them collapsing.
The important bit is how it all gets mixed together.
Now, you make 6 million Yorkshire puddings here a day, but your mixing paddle is tiny.
Why's it so small?
In the flour, the protein structures are like elastic bands
and if you apply too much pressure you cut those strips of elastic.
When the products rise, the structure won't be able to hold itself at the setting stage
and the Yorkshire pudding will fall back.
Now, Stuart, this is looking a bit similar to how I do it at home. Hot trays, putting the oil in.
The right amount of oil is very, very important,
because if you have too much it will rise but you won't get the well and it will be very soggy at the base.
Then, in goes the all-important batter.
Next stop for the puds is the oven.
And what an oven it is! It's incredible. It's huge.
It looks more like a room, not an oven.
That's correct. It's about half the length of a full-size football pitch.
It's actually four different ovens within one.
This massive oven is split into four temperature zones.
In zone one, the puddings are heated nice and gently.
The second is much hotter and here the Yorkshires start to rise.
Around the outside of each individual pot,
the batter's starting to come up the side of the pan.
And we can have a quick look - because it's such a big oven,
it doesn't make a difference. But at home...
At home you would lose your product. That's where I go wrong. Correct. I'm too eager.
Zone three is the real furnace and that's where the puddings set.
Finally, in zone four, they turn that tasty golden colour.
Stuart cooks his Yorkshire puddings for 15 minutes.
It's time to see if he's kept his Yorkshire pride.
Have they all risen?
Stuart, are you telling me you check every single Yorkshire pudding?
Every single Yorkshire pudding.
What makes a bad Yorkshire pudding? A bad Yorkshire pudding
is any misshapes like that...
That's a bad one. ..with a split in it.
What about that one? No, we'd reject it.
That's gone. How about that one?
That's OK. That's borderline.
That's borderline. Is Stuart any good at this?
I think so. He's not taken one off and eaten one, has he?
Oh, no, no, no!
For me, the proof is in the eating.
Can I try one? You can try one.
Right. I'll have one of those.
Lovely.
Mmm! I want her job.
Finally the Yorkshires are frozen, packed and sent to the supermarkets.
But feel free to boast that you made them yourself.
Your secret's safe with me.
A lovely cup of coffee to finish off your Sunday roast.
Right, how do you like your coffee? Decaffeinated or full-bodied?
Decaff, please. Decaff? Right. Caffeinated, please.
I prefer caffeinated, please, Jimmy. Definitely caffeinated.
Most people think that coffee and caffeine go together like bacon and eggs.
But a tenth of all coffee sold in Britain is decaff.
So how do you get the caffeine out of coffee?
This white powder is pure caffeine.
It's the amount you'd get from half a kilo of coffee beans, which is about the same as 50 cups of coffee.
But if you don't want that caffeine kick, how do you ditch the caffeine but keep the flavour?
The first thing I need to do is build a steamer, powered by these wallpaper steamers.
In here go some raw, green, unroasted beans.
Coffee beans are tough little blighters, so this steamer will soften them up a bit
and make the caffeine inside a bit easier to get at.
It should take me about an hour.
Woo! It's like a sauna.
Let's have a little...
They're really soft. Perfect.
That's going to really help me get the caffeine out of these beans.
Let's take them over to my decaffeinator.
It's really a fish tank with a heater.
But my barn, my rules!
If the water's hot enough, the caffeine will dissolve in the water.
You simply wash it out of the coffee beans.
The only problem is, it's like when you clean the dishes at home.
The water can get dirty, or in this case filled with caffeine.
To get as much caffeine out of the beans,
I need to clean the caffeine out of the water.
So I'm going to pump the water through a filter.
I'm filling it with something called activated charcoal.
The charcoal's honeycomb structure is great for trapping caffeine molecules.
So they stay in the filter and the water gets cleaned.
It's one of a number of ways the food factories can remove the caffeine.
Now it's a waiting game for my coffee beans to become decaff coffee beans.
One thing I haven't told you is that as well as washing the caffeine out of my beans,
I've also washed away lots of other things, including the bits that give the coffee its flavour.
Far from being a disaster, this is actually the clever bit.
The coffee flavour gets washed out of the beans but it stays in the water, turning it this dirty green colour.
Now, if I add fresh beans to this dirty water,
the flavour in these new beans has nowhere to go.
That's because the dirty water is already full of coffee flavour,
and there's no room for any more.
The same can't be said for the caffeine.
The new beans can still lose their caffeine because that gets trapped in the charcoal filter.
So my new beans will have the caffeine washed from them but they can't release their flavour. Genius!
And it's these new beans that I'm going to use to make my gourmet decaff coffee.
Right. Let's get them out on this tray...
After a few hours' soaking, they're ready for roasting.
You can that they've become really black and shiny.
That's all the oil coming out. With the oil, that lovely smell of coffee.
Oh! Ho, ho. That's so strong it went right up my nose! But the aroma,
absolutely delicious.
It might smell good, but is there any caffeine in there?
Going to do a little test to see if I've actually decaffeinated my coffee.
First, I've got some normal instant coffee.
I'm going to pop one of these strips into this coffee here.
This will detect the presence of caffeine.
If there's caffeine present, I should see just one pink line appear across the paper.
Right, well, on that strip it's really, really faint, but there's only one line.
That tells me there's caffeine present in that coffee.
So what about MY coffee? Is it decaffeinated? Let's see.
Right, in goes my strip.
Now, if the coffee's decaffeinated, TWO lines should appear.
Never think you'd get nervous over coffee, would you?
And there we have it.
One, two.
Two little lines, which shows me I've decaffeinated my coffee.
Let's have a taste.
Lovely aroma.
Actually, that's surprisingly stronger than it looks.
Good flavour.
I'm really, really pleased with this. This has worked wonders.
It smells so fresh.
There we go. My very own decaffeinated coffee. Fantastic.
Later on, we brewed up some more.
Would it refresh or repulse?
Strong. It's quite strong. Bitter. I don't think you could take too much of that.
I don't think it's too bad, actually. You quite like it? Yes. That's strong. Bitty.
I don't know what you mean!
Looks like it's been up and down the chimney.
A bit sooty, a bit bitty.
They're a couple of puppets, aren't they? Sooty and Bitty.
I actually filtered that through an aquarium filter. Did you?
Yeah, to try and get the caffeine out. Was it clean! Well, the fish didn't mind!
Do you want some more? No, thank you.
Roast dinner has got to be one of the most traditional meals and I reckon
high-tech science has brought it bang into the 21st century.
Subtitles by Red Bee Media Ltd
Email subtitling@bbc.co.uk