Where do you reckon on the fish the fingers come from?
On here? That bit. This bit?
Children can be real fussy eaters,
but when they see something on the supermarket shelf they want,
there's no stopping them.
So how do they make kids' favourite foods?
Who likes chocolate Mini Rolls?
How would you get them to roll perfect every time?
Would you make a giant one as long as your field?
What do you reckon your marshmallows have got in common with that big pig there?
Do you think the piggy's made out of marshmallows? No.
No? I'm going to reveal the secrets behind children's party foods
by making them food factory style.
Most of us don't get the chance to go inside a factory
to see how our food is made,
so I'm going to go back to basics and set up my own supermarket production line inside this barn.
It may look like it's full of junk,
but there's everything I need
to discover the secrets of the supermarket foods that kids love.
Marshmallows, toasted or not, are a kids' favourite.
But what have they got in common with this beauty?
What do you think? What have your marshmallows got in common with her?
A bit of white on them. I'd rather eat her than them.
Do you think the marshmallow's nice and squidgy and so is the pig? Yes.
Yes! Now I like pigs and I like marshmallows,
but what's the connection?
To find out, I'm going to make my own.
Marshmallows might look like lovely little cushions of sweetness,
but I'm about to blow that image out of the water.
The important ingredient to a marshmallow is gelatine
and gelatine is made out of pig skin and bones.
It's in all kinds of foods.
It's used as a thickener or gelling agent in jelly,
gummy sweets, mousse and of course marshmallows.
Off-putting as it may seem, gelatine is made by breaking
down an ingredient in animal skin and bone called collagen.
It gives our skin its firmness too.
To get at the collagen inside my pig bits, I've got to treat it with acid.
That's why I'm wearing
all this protective gear.
Right, time for the acid.
The acid will loosen the collagen
and make it easier to turn it into gelatine.
Seems a bit gruesome.
A million miles away from marshmallows.
Now, there are veggie alternatives to gelatine
but no direct replacement has been found
that matches gelatine's unique properties.
What gelatine does is to form a very stiff gel that melts in the mouth.
But this piggy-flavoured concoction
is still a long way from melting in anyone's mouth.
It'll take hours for the acid to loosen the collagen.
Now, I've got rid of all the traces of acid.
The next part of the operation is to turn my pig bits into a lovely soup.
I'm putting together a simmering soup cooker to get at the gelatine.
Right, this should do the job.
I'm adding a heating element to the bucket to keep the water
at 50 degrees Centigrade.
If you've ever made chicken stock at home by boiling up the bones
of your leftover Sunday roast, well, this is very similar.
It will have to soak for eight hours.
I'm left with this piggy stew that smells pretty meaty.
Next, I have to filter it.
I need a liquid containing gelatine to make my marshmallows set
or it's eight hours literally down the drain.
It's a bit whiffy.
It's a cross between pork scratchings gone bad
and the smell of wet dogs.
Right, need to pour it into this demijohn.
That is one smelly pork stew.
Time to put my gelatine stew to one side and get on with the sweet stuff.
Right, into this pan I'm going to put some white sugar.
Now, this gloopy liquid is glucose syrup.
It's going to make it really sweet.
Keep it on the heat, keep mixing until it all clears.
But there's still one essential ingredient missing.
Marshmallows are filled with thousands of tiny air bubbles,
that's why they're so squidgy.
To prove it,
I'm going to do something alarming with this marshmallow man.
I'm going to suck the air out of this jar.
As the pressure drops in the jar,
the air bubbles inside my marshmallow man
will begin to expand.
Look at his body swelling up.
Be great if you could do this with all foods. Look at him!
He's nearly at the top of the jar.
Is he still smiling?
The secret of a successful marshmallow is lots of air.
Time to put it all together.
First the stinky stew.
Well, it still hasn't lost any of its aroma.
OK, let's measure it out.
There we go.
Look at that. Lovely and gloopy.
Hopefully it's packed with gelatine.
OK, mixing bowl.
Because I'm dealing with hot sugar,
I need these on and I'm using this -
my super whisker.
Right.
Now, this is pretty much all there is
to factory-style marshmallow making.
But will I get enough bubbles into this gloop
to make really squidgy marshmallows?
Now the sugar and the gelatine are in the bowl,
the key thing is to increase the mixing speed
because that is critical to getting more air bubbles in there.
The more air bubbles I get,
the more spongy and fluffy the marshmallows will be.
Time to add a splash of colour with beetroot extract
and a few drops of vanilla.
The air bubbles also help make the mixture whiter.
I think that's thick enough. I've whisked loads of air in there.
I need to get it into a mould.
Ta da! There we go, look at that.
Ice cube trays, now marshmallow moulds.
Right.
It's beginning to look and smell more and more like marshmallows.
Might plaster the bathroom later.
Here we go.
All I need to do now is let them set.
Right, let's look at these beauties.
Got to get them out.
Here we go. Look at this.
You would never dream that this has come from all that pig skin.
Look at that.
Cover it in some icing sugar.
Isn't it amazing what you can do with acid-treated pig skin?
Look at that.
Squeeze. Whoop, whoop.
Holds its shape. Not bad at all.
Let's open it up because the marshmallow
is all about the air bubbles.
Little bit gooey.
Almost like blancmange.
I reckon the gelatine should have been a bit thicker, maybe.
You can see the air bubbles there. Look at that!
I think for a first attempt that's not bad for pig skin.
Let's have a little taste, see what it feels like in the mouth,
because it looks really gooey.
Feels nice.
Tastes a little bit piggy.
Yeah, looks can be deceptive!
There we go. My very own marshmallows.
We made up another batch later on.
How will they go down on the farm?
Oh, they're lovely. Lovely?
Beautiful. Beautiful?
When I made them first, they did taste quite piggy.
Very sugary. Do you know what they've got in common with the pig? Is it gelatine, something like that?
Gelatine. Yeah, the pig's head and the trotters. Fancy another one?
No, thanks.
Really? I can definitely taste some.
Not too bad, you've eaten three.
There we go, guys.
There's one thing you can't get enough of at kids' parties
and that's puddings.
Strawberries and cream,
absolutely delicious, or even better, raspberries.
But these little fellas are hiding a secret.
On this tray,
which ones are berries?
Raspberries. Raspberries. You say that's a berry, would you?
You think they're berries? Do you think any others are berries here?
No. Grapes probably are a berry, there's a possibility.
If anything I would say these might be, but that's about it.
Bananas are not, grapes are not.
Well, in fact they're all berries except the raspberries. Really?
That's a berry in name only.
Rubbish. No, it's true. Do you believe any of this? No!
Although it has 'berry' in its name, a raspberry isn't technically a berry.
A berry is a simple, single fruit like a grape or a banana.
But a raspberry is made up of lots of tiny fruits all clustered together.
So in a way, a raspberry is a bit like an entire bunch of grapes.
But where you'd find a raspberry in a plant encyclopaedia
isn't the only surprising thing about them.
Raspberries are incredibly fragile fruit.
They're easy to squish and the bugs love them.
So how do they get them from the plant to the supermarket in one piece?
Mark Gaskain produces around 70 million raspberries every year.
Hi. Nice to meet you.
Now what are the difficulties in growing raspberries?
They're a bit soft, aren't they? You've got them under a house here.
Raspberries are probably the most delicate fruit we grow here.
The reason they're under the polytunnel is to protect them from the rain, wind,
and actually heat as well, heat and sunlight.
Mark treats his raspberries like the supermodels of the farm.
These delicious divas are high maintenance.
They are a bunch of luvvies, aren't they? They are a little bit.
That's exactly what the strawberries say about them.
But these cuties can attract the wrong kind of attention -
biting, sucking, piercing bugs
that love a tasty raspberry,
like the raspberry beetle and the aphid.
But these bad boys may have met their match.
This high-tech kit is the latest line of defence
in keeping the raspberries picture perfect.
It storms the bugs with air heated to 100 degrees C.
It's like a giant hair dryer.
What we're doing is blasting it with the fans.
We're driving through the raspberry canes
and for a very brief period of time hitting it with a lot of heat.
It's killing any pests it hits.
Things like aphid in particular it's very effective on.
Basically you're barbequing these plants very, very quickly,
which kills the bugs off but the plants are left unharmed.
Exactly. And you're reducing your pesticide usage
because you're doing this with a barbeque rather than a sprayer.
I should've brought some sausages! You should have done!
But there's no time for a barbecue.
This machine looks a blast and I want a go.
Scientists aren't exactly sure how this machine works.
One theory is that as well as getting rid of the bugs, the heat
shock makes the raspberry bushes tougher
so they're more resistant to being attacked by insects.
Just what these pampered softies need.
Well, that was a lot of fun. How was it?
It was good! So Mark, how well has this kit done on other farms?
Well, what it's done very well so far... grapes in particular,
in New Zealand and I think Chile have done really well out of it.
Still early days for us with raspberries.
You're at the cutting edge.
You're not just giving your raspberries a bit of pampering with a blow drier?
Er, no. Blow dry and set?
Not today. No, this is genuinely pesticide reduction.
Fewer pesticides can't be bad and fewer bugs
means all the more raspberries for us.
So this is obviously the picking process.
Can we have a go? Yeah, please do.
Obviously quite straightforward. Pluck them off. Pluck them off?
If it's properly ripe, they should come away nice and easily.
So the idea is gently coax them off and keep that lovely shape.
They're all picked by hand, aren't they? Absolutely.
They're only touched once. Only touched once? Just once.
The whole point of this is trying to get it right in the field. So we pick it carefully,
grade it in the punnet so that it's all the same standard.
There's no reason to touch these again until they arrive
in Mrs Jones' fridge in Worcestershire.
If these raspberries could talk,
they wouldn't talk to the likes of us, would they? No! Certainly not.
These raspberries have had five-star treatment all the way,
so I reckon this is going to come as a bit of a shock.
Delicious!
A real party favourite, fish fingers.
Now I've got a whole cod here.
Look at that. Look at the head on him.
But this beauty would soon go off if I left him sitting here.
So how do the food factories try to make frozen fish
taste like fresh fish?
To find out, I'm going to make my own premium fish fingers.
First, I need to build a fish freezer.
I've got a bucket, a metal tray,
some copper piping and a load of rubber tubing.
Mm. I know what I'm doing. When it comes to freezing fish
and turning it into fingers, no-one knows more than Clarence Birdseye.
You might have heard of him.
Before he set up his frozen food empire,
Clarence Birdseye was a scientist.
He visited the Arctic and saw people freezing fish very quickly in the icy conditions.
When cooked though,
it was very hard to tell it apart from freshly caught fish.
And that gave him a very cool idea.
Clarence Birdseye reckoned that it was freezing the fish fast that made it taste good.
So he invented a fast-freezing plate.
I'm trying to do the same thing with my tubes, ladder and bucket.
This is my plate freezer.
Now I'm going to put some really cold liquid in this bucket
which is going to flow through this tube, along this piping.
It's going to chill these trays well below the freezing point
of any food I put between them.
I'm using methylated spirits, also known as white spirit, because it stays liquid at
very low temperatures, so it won't freeze solid and block the pipes.
I'm going to put this dry ice into these metal containers which will chill down the white spirit.
Dry ice is solid carbon dioxide at minus 78 degrees C.
I just need to pop the container into my bucket of meths.
I'll leave it to get really cold and while that's happening,
I can get to grips with the fish.
Now the first thing to do is start off with lots of fish fillets.
The fillets are then packed in trays and then frozen so you end up with great big slabs of solid fish.
And hopefully every bit of the fillet will find its way into a fish finger.
Back at the plate freezer, the meths has been chilling away nicely.
But is it cold enough to fast-freeze my fish?
Right, let's give it a go. Turn the tap on.
It's all frosted already at the top.
The tap's frozen.
Oh, there we go.
I can hear it, so it's making its way all the way through this tube.
Let's feel it. That is really, really cold. Ooh!
The meths is being chilled by the dry ice.
My plate freezer needs to be about minus 30 to freeze the fish quickly.
The colder it is, the faster the fish will freeze,
and fast-freezing is the secret to decent fish fingers.
Wow, look at that.
That's well below minus 30, which is fantastic, really, really cold.
Time to freeze the fish.
In go a dozen fillets of fish.
Like a polar bear's dinner in there.
Now, put the pillows on.
That'll keep the cold in.
Perfect.
I'll come back to my fish in a couple of hours to see how they're getting on.
Kids love Mini Rolls, but if you've ever tried to make a Swiss roll,
then you'll know how hard it is.
Do you think you could eat all that? No.
So how could you roll millions of these without cracking up?
At this factory in Liverpool, they make 15,000 Mini Rolls an hour.
Every single one has to roll perfectly and it's down to John Reid to make sure that happens.
So what are the big problems when you're making a Mini Roll?
Basically, we've got to make sure we can roll it correctly
without either it springing open or cracking.
We don't want it to crack.
They start by making the batter in this high-speed batter mixer.
So all the ingredients in here now all looking really good.
Is this ready to go?
Apart from one ingredient, Jimmy. What's that? Air. You put air in?
Air is piped into the mixture to create millions of tiny bubbles.
It's the ingredient that helps make the batter exactly the right
consistency for its big moment - rolling.
It's so important they test every batch.
We take a little cup with a specific volume.
It's got a little hole in the bottom and we measure
how much batter falls through that little hole in one minute. Right.
So if it runs out really quickly. It's very thin.
If it takes ages, it's too thick. If it dribbles out like that?
Just right. Just right.
So ready to bake? We're ready to bake now, Jimmy. Perfect.
The man who turns the batter into spongy Mini Rolls is Tony Monks.
This is where we put our batter onto the conveyor belt to go into the oven for baking.
What's stopping the mixture from spreading out all over the place?
Because the batter's so consistent and it's got air within there, it holds the structure together.
And you've got this really snazzy James Bond laser beam here.
What's that for?
That measures the height of the batter and the width of the batter.
If it's is just one millimetre too thin or too thick,
it could be all over.
It's important for the rolling process, to stop it from cracking.
If you don't get the right height, you won't be able to roll it?
We won't. So where's it going now, then?
It's now going through the conveyor and into the oven.
Right, baking time. It is baking time.
Ah, look at that. That has risen, hasn't it?
Yes, this is where we start to see the cake rise.
Look at this. Is this cooked properly? It is, yes.
It's spongy, isn't it? It's very springy.
What's the underneath like?
If you look at the underneath, it's slightly harder. So we've got a harder base.
Look at that. Hang on, isn't that hard, crusty bit meant to be on top?
That's why we've got the big wheel at the end to turn it over.
With the sponge baked, it's time to add the filling.
It still doesn't look very roll shaped.
Ah, right. So this is where you cut it and roll it?
No, this is just where we roll it, but we roll it lengthways.
To roll it lengthways, the flat sponge is lifted up by thes
metal plates at the end of the line.
One side of the sponge is tucked under the other.
If the batter is spot on, it should emerge looking more roll shaped.
Looking good, no cracks.
But hang on! These aren't Mini Rolls.
They're over six metres long. They're Maxi Rolls.
They need trimming, and not with a kitchen knife.
When you get a normal knife and a Mini Roll and you cut it...
Oh, I see.
Because that pressure squeezes the sponge down, you end up with a flat end, don't you? It does, yeah.
And that won't do.
Tony's knife vibrates up and down thousands of times a second.
The blade cuts through the Mini Roll using hardly any pressure.
The result - a razor-sharp slice.
Mums, you can rest easy.
The Mini Rolls are rolled, packed and on the way to the supermarkets.
All it took was intricate ingredient engineering
and a very, very fast knife.
Back at the barn, I'm making fish fingers from fish fillets,
like the posh ones in the supermarket.
So far I've tried to fast-freeze a big slab of fish.
But will it have frozen fast enough?
I've got this piece of fish to show you the difference
between fast-freezing and slow-freezing.
Last night it was frozen slowly over nine hours.
Look what happens now that I've defrosted it.
Look at that.
It's like a sponge.
If I cooked that, it would be really, really dry and a bit tough.
That's because all the moisture that's leaked should still be
in the fish flesh, but as the fish freezes it seeps out.
So the longer the freezing takes, the worse it gets.
To prove it, I've got a bit of fish that's been fast-frozen.
Let's give it a squeeze.
I can really squeeze it. I don't want to mash it, but look.
Hardly any water at all coming out, which means
if I cook that bit of fish, it should stay nice and succulent.
So will my fish fingers be juicy and flaky or dry and tough?
Right, the fish has been in here for about two hours now.
I've put a little bit of dry ice on top just to help with the freezing.
Now the temperature probe is right in the middle of the fish
and it's reading at minus 25 degrees,
which means the fish has frozen really quickly.
Just what I wanted.
Fish fingers crossed, then!
Now to open my plate freezer and take out the fish. Look at that!
Now that is one slab of fish. Look at it.
You can see all the fillets along here, all the muscles of the fish.
It's like a big, fish sandcastle.
There we go, look at that. Now for the clever bit.
I've got to turn this into fish fingers,
which involves sawing it up.
My frozen fish is so tough I'm slicing it up with a power saw.
This is pretty much how they do it in the factory.
OK, here we go. I'm going to saw
my fish up. I'll be very careful.
It's working.
Look at that!
Look at that.
It's a little bit thick
but properly home-made. I'm pleased with that.
That's beginning to look like a fish finger.
The final step is to give them a coating of batter and breadcrumbs.
These aren't finished yet. To stop the breadcrumbs
coming off in the packet, I'm going to give them a quick fry.
Now, I'm not cooking these.
The idea is to give them a really, really quick fry because I want to
make it nice and crispy but I want to keep the fish frozen.
So they get just 25 seconds in the deep-fat fryer.
Then it's back into another freezer to chill down the coating
and off to the supermarket.
But I want to taste some of mine, so I'm cooking a few in the oven.
Will they be succulent and flaky or tough as old boots?
Now, I know what you're thinking.
They're not exactly fish fingers,
are they? More like fish thumbs.
Right, let's have a look.
A bit fat. Great colour.
The important thing,
what I'm really looking for,
is that beautiful flakiness.
Oh, yes, look at that. Look at that when I open it up.
It all opens up and you see all those flakes.
Brilliant.
Mmm.
Good crunch.
Good flavour.
Really, really flaky.
And they're deliciously juicy.
Just what I wanted. Got to say - success.
Really got the flakiness, didn't get the shape.
Next time they're going to be more like fingers.
There we go. My very own fish fingers. Delicious.
Next time you're in a supermarket with the kids, you can tell them what's really in a marshmallow,
how to roll a Mini Roll and what makes fish fingers so tasty.
Food Factory answers to supermarket secrets.
Subtitles by Red Bee Media Ltd
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