0:00:02 > 0:00:06As a nation, we consume over 20 million litres of milk every day.
0:00:06 > 0:00:10And right now, factories across the country are processing
0:00:10 > 0:00:12milk from nearly two million cows.
0:00:17 > 0:00:21It's a modern-day miracle that we all take for granted,
0:00:21 > 0:00:23but it's a race against time.
0:00:24 > 0:00:27Cow to carton in 24 hours.
0:00:30 > 0:00:32How do they do it?
0:00:32 > 0:00:35Well, tonight we are taking you inside one of the largest
0:00:35 > 0:00:39fresh milk-processing plants on Earth to find out.
0:00:42 > 0:00:46'I'm Gregg Wallace and I have been given exclusive access to see how
0:00:46 > 0:00:50'this dairy factory can process 2,000 litres of milk
0:00:50 > 0:00:52'in under a minute.'
0:00:52 > 0:00:55We've got raw milk here, we start to warm it up, warm it up
0:00:55 > 0:00:57and then we homogenise it.
0:00:57 > 0:01:01'How cutting-edge science is used to create the perfect drop.'
0:01:01 > 0:01:03We do a bit of a taste, just like you would taste a good wine,
0:01:03 > 0:01:04it's just milk.
0:01:04 > 0:01:08'And how new technology will change the future of milking.'
0:01:08 > 0:01:12Mate, I love this. I absolutely love this.
0:01:12 > 0:01:16'I'm Cherry Healey. I'll be following the milk off-site to show how
0:01:16 > 0:01:18'it makes cheese on an epic scale.'
0:01:18 > 0:01:20Now this is where we see the curds and whey.
0:01:20 > 0:01:25Oh, whoa! Eugh! Eugh, that's like scrambled eggs.
0:01:25 > 0:01:29'And revealing how milk makes the nation's favourite dessert.'
0:01:29 > 0:01:32That may be the most beautiful thing I've ever seen.
0:01:32 > 0:01:34COW MOOS
0:01:34 > 0:01:36Along the way, historian Ruth Goodman will
0:01:36 > 0:01:39investigate our complicated history with the white stuff.
0:01:39 > 0:01:41With the invention of the steam engine
0:01:41 > 0:01:45we could bring their milk at top speed into the cities.
0:01:45 > 0:01:47'We'll be meeting robots.'
0:01:47 > 0:01:51Whoa, whoa. Argh.
0:01:51 > 0:01:54'And people who have worked in dairies all their lives.'
0:01:54 > 0:01:56Been in this business 18 years, in a fridge.
0:01:56 > 0:01:58I effectively was a robot.
0:01:59 > 0:02:03Most days, 1.5 million litres of milk will pass through
0:02:03 > 0:02:06here on the way to your supermarket shelf.
0:02:06 > 0:02:10This is the incredible story of the factories that feed Britain.
0:02:26 > 0:02:30Tonight, I'm going to show you the remarkable journey of milk
0:02:30 > 0:02:34through Arla Dairies, one of the biggest producers of milk,
0:02:34 > 0:02:35cheese and butter in Britain.
0:02:38 > 0:02:43It's a cooperative, owned by 13,500 farmers across Europe,
0:02:43 > 0:02:45including Neil and Jane Dyson.
0:02:45 > 0:02:46They're cute, aren't they?
0:02:46 > 0:02:50I've come to their third-generation dairy farm in Buckinghamshire
0:02:50 > 0:02:55to see how it all begins, with a herd of 500 Holstein Friesians.
0:02:55 > 0:02:59Here's your Uncle Greggy, I've come to give you some lunch.
0:02:59 > 0:03:02The Dysons rear 120 young heifers a year
0:03:02 > 0:03:05that are specially bred to produce milk.
0:03:05 > 0:03:07How do we go from baby cow to milk?
0:03:07 > 0:03:10When they're 15 months old, they'll get pregnant for the first time.
0:03:10 > 0:03:13Then they'll have their first calf when they're two years old
0:03:13 > 0:03:15and then they'll start producing milk.
0:03:15 > 0:03:17Cos obviously - no calf, no milk.
0:03:17 > 0:03:20How can you guarantee that every different heifer is going to
0:03:20 > 0:03:23fancy the same looking bull?
0:03:23 > 0:03:25It's not been a problem in the past.
0:03:27 > 0:03:30After calving, cows produce milk for nine months,
0:03:30 > 0:03:33then they need to be artificially inseminated to keep having
0:03:33 > 0:03:35more calves and keep producing milk.
0:03:35 > 0:03:42I have to confess to being slightly uncomfortable with so many big cows.
0:03:42 > 0:03:44- Oh, yeah.- 700 kilos.
0:03:44 > 0:03:45Don't let 'em get me.
0:03:45 > 0:03:48That one's going to slip over, fall over and crush me.
0:03:52 > 0:03:53Come on, girls.
0:03:53 > 0:03:55'Milking starts at 4.30 in the morning,
0:03:55 > 0:03:59'and every day the Dysons milk for 16.5 hours.'
0:03:59 > 0:04:02This one's hiding at the back, come on.
0:04:02 > 0:04:04I'm going to help.
0:04:04 > 0:04:05Are you ready?
0:04:05 > 0:04:06No, I'm a little bit nervous.
0:04:06 > 0:04:10It's not tricky once you've done it a few hundred times.
0:04:14 > 0:04:18So you're now looking at the backside of 34 cows.
0:04:22 > 0:04:24Would you like to choose your cow?
0:04:24 > 0:04:25This one.
0:04:25 > 0:04:28OK. You hold her there and you squeeze down.
0:04:28 > 0:04:30Before we can get started
0:04:30 > 0:04:33we need to check for something that all dairy farmers fear.
0:04:33 > 0:04:35Right, her milk's good.
0:04:35 > 0:04:38If she's got mastitis, which is an infection,
0:04:38 > 0:04:40then it would be watery with horrible clots.
0:04:40 > 0:04:44If they have mastitis, we must make sure we give her some antibiotics.
0:04:44 > 0:04:47And if we do that then she mustn't be milked with the rest of
0:04:47 > 0:04:50the cows, she must be kept separate, cos you and I must not have
0:04:50 > 0:04:54that milk that's had the antibiotics in it, we must throw that away.
0:04:54 > 0:04:57Put your finger inside here.
0:04:57 > 0:04:59And can you feel pulse, pulse, pulse?
0:04:59 > 0:05:00Yeah, yeah, yeah.
0:05:00 > 0:05:03That's the sucking, like the baby calf would suck you.
0:05:03 > 0:05:05Take this and put it onto her teat.
0:05:07 > 0:05:09You can hear it sucking, can't you?
0:05:09 > 0:05:11Oh, that's it. Yeah, that's it. You got that one.
0:05:11 > 0:05:13You're OK. There you go.
0:05:15 > 0:05:20Number three and number four.
0:05:20 > 0:05:23And, if you look in here, you can actually see the milk.
0:05:25 > 0:05:29In around 24 hours, this milk will be bottled and ready to drink.
0:05:31 > 0:05:33Do you refrigerate the milk straight away?
0:05:33 > 0:05:37Before it goes into our big tank it's cooled to three degrees C.
0:05:39 > 0:05:41When there's no more milk coming out
0:05:41 > 0:05:43the machine stops milking automatically.
0:05:43 > 0:05:47There it goes, automatically off.
0:05:47 > 0:05:48THEY LAUGH
0:05:48 > 0:05:51I'm never going to see a bowl of breakfast cereal
0:05:51 > 0:05:53in the same way again. Ever.
0:05:57 > 0:06:00The Dysons' cows produce 12,000 litres a day,
0:06:00 > 0:06:05which is destined for the enormous dairy factory 13 miles away
0:06:05 > 0:06:08in Aylesbury, Buckinghamshire.
0:06:08 > 0:06:121.5 hours after milking, Paula Da Silva Pereira arrives
0:06:12 > 0:06:15to collect the milk in an insulated tanker
0:06:15 > 0:06:18which will keep it chilled at around three degrees.
0:06:18 > 0:06:21The Dysons are paid according to the quality of the milk,
0:06:21 > 0:06:24so a daily sample needs to be taken.
0:06:24 > 0:06:26What do we want in the milk?
0:06:26 > 0:06:29We want good fat. We want high protein.
0:06:29 > 0:06:31I mean, what does it vary by?
0:06:31 > 0:06:33It could vary by 10%, which doesn't sound a lot,
0:06:33 > 0:06:36but for us it could mean a penny or two per litre.
0:06:36 > 0:06:3812,000 litres, every day.
0:06:38 > 0:06:40- That could be the profit.- Yeah.
0:06:42 > 0:06:45- Perfect.- Do we test this or does this go off now?
0:06:45 > 0:06:47- It goes off, yeah. - They don't trust us to test it?- No.
0:06:47 > 0:06:51Well I'm a food and drink expert, as you know, and let me tell you...
0:06:51 > 0:06:52this milk looks really good to me.
0:06:52 > 0:06:55- Oh, brilliant.- All right. Don't worry about a thing.
0:06:57 > 0:06:59Come on, Gregg.
0:06:59 > 0:07:00Oh, crickey.
0:07:03 > 0:07:04It's like being a fireman.
0:07:05 > 0:07:09I'll catch up with the Dysons' milk later at the dairy factory,
0:07:09 > 0:07:13after Paula has finished the remainder of her 96-mile route,
0:07:13 > 0:07:15collecting from two other farms.
0:07:16 > 0:07:20Well, there's a truck full of milk just left the farm, but that is
0:07:20 > 0:07:24just one of tens of thousands delivering milk all over the nation.
0:07:24 > 0:07:27And we go through milk in huge quantities.
0:07:27 > 0:07:31Actually, the fact that we can drink milk in that much quantity
0:07:31 > 0:07:32really makes us quite unusual.
0:07:38 > 0:07:41Almost all of us can digest milk as babies,
0:07:41 > 0:07:44it's a trait we share with other mammals.
0:07:44 > 0:07:48But, amazingly, there's only one mammal that can keep
0:07:48 > 0:07:51digesting milk into adulthood and that's us.
0:07:53 > 0:07:57Even then, as much as two thirds of the world's adult population
0:07:57 > 0:07:59find milk difficult to stomach.
0:07:59 > 0:08:01Every time you try and get to sleep,
0:08:01 > 0:08:03it feels like a witch's cauldron's going off in your stomach.
0:08:03 > 0:08:10If I have a lot of it then I can spend some time in the bathroom.
0:08:11 > 0:08:15What is it about milk that some of us can't tolerate?
0:08:17 > 0:08:21Whole milk is made up of 87% water,
0:08:21 > 0:08:258.3% protein, fat and vitamins combined
0:08:25 > 0:08:31and 4.7% milk sugars, called lactose, which can cause problems.
0:08:32 > 0:08:36During childhood, many of us stop producing an enzyme called lactase
0:08:36 > 0:08:39which helps break down the milk sugars
0:08:39 > 0:08:41and they become lactose intolerant.
0:08:41 > 0:08:44It's a condition that's surprisingly common.
0:08:48 > 0:08:52About 50 million Americans struggle to digest milk.
0:08:53 > 0:08:56In the South of France, half the locals must say "non"
0:08:56 > 0:08:58to a glass of the white stuff.
0:09:01 > 0:09:08And for the Chinese, astonishingly, 90% of them are lactose intolerant.
0:09:16 > 0:09:21So why is it that so many people in the world have a problem with milk?
0:09:23 > 0:09:26The man who should know is Professor Mark Thomas.
0:09:26 > 0:09:31He's been studying evolutionary genetics for 22 years.
0:09:32 > 0:09:34What is this?
0:09:34 > 0:09:38OK, so this is the piece of DNA sequence around the bit that
0:09:38 > 0:09:41controls whether you digest the sugar in milk.
0:09:41 > 0:09:46So, this DNA sequence is what most people have?
0:09:46 > 0:09:47Most people in the world, yes.
0:09:47 > 0:09:53And most people who have this DNA sequence cannot digest lactose.
0:09:53 > 0:09:56- That's right. - They cannot drink milk?
0:09:56 > 0:09:57That's right. As adults.
0:09:57 > 0:10:01So, if the norm is to not be able to drink milk, what happened?
0:10:01 > 0:10:04How come most of us here in Britain can?
0:10:04 > 0:10:06Well, we're unusual.
0:10:06 > 0:10:09People in northwest Europe are generally what
0:10:09 > 0:10:12- we like to call freaks of nature. - SHE LAUGHS
0:10:13 > 0:10:17Scientists think the reason most Europeans can drink milk,
0:10:17 > 0:10:20is because of a random genetic mutation that
0:10:20 > 0:10:23first occurred in Hungary thousands of years ago.
0:10:24 > 0:10:28There's been a change in this DNA sequence
0:10:28 > 0:10:31somewhere in the last 10,000 or 12,000 years.
0:10:31 > 0:10:35This one here will be changed to that.
0:10:36 > 0:10:43And that's only one in 3,000 million of these letters in your genome.
0:10:43 > 0:10:45- It's just one, just that one change. - That's it?
0:10:45 > 0:10:47- That's it.- That's the difference between me
0:10:47 > 0:10:51- being able to have a milkshake or not?- Yeah.
0:10:52 > 0:10:56Some theories suggest being able to drink milk would have been
0:10:56 > 0:10:59a huge advantage in times of famine.
0:10:59 > 0:11:01You were much more likely to survive
0:11:01 > 0:11:05if you were able to digest such a nutrient-rich food.
0:11:07 > 0:11:11So the lucky mutation from C to T in the gene sequence
0:11:11 > 0:11:16quickly spread across Europe where most of us can now drink milk.
0:11:19 > 0:11:24So, do I have this genetic mutation that makes me tolerant to milk?
0:11:24 > 0:11:29A few weeks ago, I took a simple home DNA swab test to find out.
0:11:32 > 0:11:36I sent it off to the lab and I believe you have the results.
0:11:36 > 0:11:37I do indeed, yes.
0:11:37 > 0:11:42I wish I had a drumroll or some kind of crescendo, but I don't.
0:11:42 > 0:11:44Right. So you are...
0:11:47 > 0:11:49Yay, I'm a mutant.
0:11:49 > 0:11:51- You are, you're a mutant.- Hooray.
0:11:51 > 0:11:54Not only are you a mutant, but you are a mutant-mutant.
0:11:54 > 0:11:57You actually get two copies of this, one from your mother
0:11:57 > 0:11:58and one from your father.
0:11:58 > 0:12:02So you get a double shot at being able to digest the sugar in milk.
0:12:02 > 0:12:03Wow, I want a double latte...
0:12:03 > 0:12:06Yeah, there you go, an excuse for a double latte.
0:12:06 > 0:12:08- ..to match my double genetic mutation.- Exactly.
0:12:13 > 0:12:17So one single mutation that I and most people in Britain
0:12:17 > 0:12:22have in our genes has turned us into a national of milk lovers.
0:12:22 > 0:12:25Pretty good for a random chance.
0:12:28 > 0:12:32To see the next stage of milk, I've got to look the part.
0:12:39 > 0:12:41- LAUGHING:- Yeah!
0:12:47 > 0:12:51I am at one of the biggest fresh milk dairies in the world.
0:12:57 > 0:13:00200 people work 24/7
0:13:00 > 0:13:06processing up to a whopping 650 million litres a year.
0:13:06 > 0:13:11Enough to fill 260 Olympic-size swimming pools.
0:13:11 > 0:13:13And two hours after leaving the cow,
0:13:13 > 0:13:16the milk tanker full of the Dysons' milk is arriving.
0:13:18 > 0:13:20It's one of the 75 tankers that deliver to the
0:13:20 > 0:13:24milk intake area every day,
0:13:24 > 0:13:26overseen by technician, Colin Keyes.
0:13:29 > 0:13:31Give me some idea of the scale.
0:13:31 > 0:13:33How much milk is coming through here?
0:13:33 > 0:13:36Well, roughly, this site does about 1.5 million litres a day.
0:13:36 > 0:13:40See, it's really hard for me to get my head around that sort of scale.
0:13:40 > 0:13:41It's massive, it's massive.
0:13:44 > 0:13:46There's Paula. You all right, love?
0:13:46 > 0:13:49- Hiya.- What happens there, Colin?
0:13:49 > 0:13:52I'm going to make sure the milk that goes to the customer
0:13:52 > 0:13:54is good quality. That is my job.
0:13:54 > 0:13:55You're the bouncer.
0:13:55 > 0:13:57- I am the bouncer. - Nothing bad gets past you.
0:13:57 > 0:14:00I'm not a very big bouncer, but I'm a bouncer, yeah.
0:14:00 > 0:14:02And what Paula's going to do is get a sample.
0:14:02 > 0:14:03So why are we checking again?
0:14:03 > 0:14:06You just checked one farm, but now you've got other farms
0:14:06 > 0:14:09throwing in their milk where it could be contaminated.
0:14:09 > 0:14:11We check it before we know whether she can unload it.
0:14:11 > 0:14:13That's right, because if we don't check it,
0:14:13 > 0:14:16the milk goes into the system and we don't want that.
0:14:16 > 0:14:18Will you send the truck away if it's not right?
0:14:18 > 0:14:20Yes, it will be rejected.
0:14:20 > 0:14:23If the temperature was incorrect, it's gone, the whole lot.
0:14:23 > 0:14:27If it's over eight degrees, it's gone. Antibiotic failure, it's gone.
0:14:27 > 0:14:3024,000 litres of milk will be rejected on one farm messing up.
0:14:30 > 0:14:32Mate, that is mental.
0:14:32 > 0:14:34I'm going to check your milk and we'll be right back
0:14:34 > 0:14:36to let you know whether you can unload it or not, OK.
0:14:36 > 0:14:37OK, perfect, I will wait.
0:14:41 > 0:14:42We need to do a bit of a taste.
0:14:42 > 0:14:45With all this millions of pounds' worth of kit here,
0:14:45 > 0:14:46you still have to taste it?
0:14:46 > 0:14:49Yeah, I have to taste every single tanker.
0:14:49 > 0:14:52I just microwave it, we're basically pasteurising it.
0:14:52 > 0:14:54Just like you would taste a good wine,
0:14:54 > 0:14:55this is like a...it's just milk.
0:14:55 > 0:14:59And you smell it. Smell that. It smells malty.
0:14:59 > 0:15:01It smells good, doesn't it?
0:15:01 > 0:15:03It smells like a bedtime drink I had as a kid.
0:15:03 > 0:15:04Exactly, exactly that.
0:15:06 > 0:15:08Just checking for any taints, can you taste anything?
0:15:08 > 0:15:10Does it taste nice and clear and good?
0:15:10 > 0:15:13It tastes absolutely lovely, I just want to put some sugar in there.
0:15:13 > 0:15:15- It does taste good. - Can we cook up some more?
0:15:15 > 0:15:17We can have as much as you want, Gregg.
0:15:17 > 0:15:21Put some chocolate powder in there, it'll be excellent.
0:15:21 > 0:15:22That tastes very good.
0:15:22 > 0:15:25Now I am going to check there's no antibiotics in the milk.
0:15:25 > 0:15:28So I'm going to put it on a heating block, 180 seconds.
0:15:28 > 0:15:31We're testing for antibiotics, what is the danger to us?
0:15:31 > 0:15:34We don't want antibiotics in the milk chain
0:15:34 > 0:15:37so people sort of become immune to the antibiotics.
0:15:37 > 0:15:40Now I understand why you get so strung up about this stuff.
0:15:40 > 0:15:41We do.
0:15:41 > 0:15:45Antibiotics are given to cows that are sick, just like humans,
0:15:45 > 0:15:47and need to be carefully controlled.
0:15:47 > 0:15:50By using an indicator strip, Colin can tell
0:15:50 > 0:15:53if antibiotic molecules are present in the milk.
0:15:53 > 0:15:56We've got the fat line at the bottom and the thin line at the top,
0:15:56 > 0:15:58so we know that the milk is a good quality.
0:15:58 > 0:16:01We can go out to the tanker now, we can open the valve,
0:16:01 > 0:16:04push start and get that milk into one of those silos.
0:16:07 > 0:16:11I knew that lot would be fine, because I actually helped milk them.
0:16:11 > 0:16:14Two hours, ten minutes after milking,
0:16:14 > 0:16:17thousands of litres of Dysons' milk can now be pumped
0:16:17 > 0:16:21into one of the 12 raw milk silos that I'm underneath.
0:16:21 > 0:16:25HE CHUCKLES HAPPILY
0:16:25 > 0:16:31Yeah. There's 300,000 litres above us in each of these silos.
0:16:33 > 0:16:38Between them, these silos can hold over six million pints.
0:16:38 > 0:16:40It's a little James Bond.
0:16:40 > 0:16:41It is a little James Bond.
0:16:41 > 0:16:43But I feel a little bit uncomfortable underneath such
0:16:43 > 0:16:46- a volume of liquid.- Yeah, yeah.
0:16:46 > 0:16:49If that now split open, I'd know what a Coco Pop feels like.
0:16:49 > 0:16:50LAUGHING: Exactly.
0:16:52 > 0:16:53The Dysons' milk is stored
0:16:53 > 0:16:57in these raw milk silos for almost 16 hours,
0:16:57 > 0:16:59waiting for its turn to be processed.
0:16:59 > 0:17:03Once released, the critical next stage is the processing zone,
0:17:03 > 0:17:06where raw milk is treated under the watchful eye
0:17:06 > 0:17:10of process technician, Mario Salvador.
0:17:10 > 0:17:12Welcome to the process control room.
0:17:12 > 0:17:14What on earth is this?
0:17:14 > 0:17:16Well, the thing is that in this process control room,
0:17:16 > 0:17:17things happen very fast.
0:17:17 > 0:17:22One drop of milk is able to go from that silo into this silo,
0:17:22 > 0:17:25which is finished milk, in 55 seconds.
0:17:25 > 0:17:28So let me get this right. We have got raw milk here...
0:17:28 > 0:17:31- Yeah.- ..and it'll go through all of this.
0:17:31 > 0:17:33In 55 seconds' time,
0:17:33 > 0:17:36it's milk in here, ready to be drunk by me the customer.
0:17:36 > 0:17:38- That's correct.- Are you lying to me?
0:17:38 > 0:17:41No, definitely not, I'm going to show you.
0:17:47 > 0:17:49This is the processing floor,
0:17:49 > 0:17:52where the Dysons' milk arrives 18 hours, ten minutes
0:17:52 > 0:17:53after leaving the cow.
0:17:55 > 0:18:01Here 1.5 million litres of milk, enough to fill two jumbo jets,
0:18:01 > 0:18:04is treated in over six miles of pipes
0:18:04 > 0:18:08by a state-of-the-art, fully-automated system
0:18:08 > 0:18:10running 24 hours a day.
0:18:10 > 0:18:13When you see all of this hi-tech machinery
0:18:13 > 0:18:16it's easy to forget it's actually coming from the cow.
0:18:17 > 0:18:20All the milk here is put through a four-stage process,
0:18:20 > 0:18:24starting with separation, then standardisation,
0:18:24 > 0:18:25homogenisation,
0:18:25 > 0:18:28and finally, pasteurisation.
0:18:28 > 0:18:30The first thing we need to do is to get rid of the fat.
0:18:30 > 0:18:34The milk comes into this machine which is separated.
0:18:34 > 0:18:37That is spinning around at 4,500rpm.
0:18:37 > 0:18:41All the fat globules will go in the top, the skim will go at the
0:18:41 > 0:18:45bottom and we're going to be able to separate the fat from the skim.
0:18:45 > 0:18:48You take all the fat out at this stage
0:18:48 > 0:18:51- and then you can put it back in again.- At the end, yes.
0:18:53 > 0:18:54Once the milk is separated
0:18:54 > 0:18:57it needs to be precisely standardised
0:18:57 > 0:18:59by now adding some fat back in.
0:19:01 > 0:19:04In the standardising machine, the computer controls how much
0:19:04 > 0:19:07fat is added back into the skimmed milk.
0:19:07 > 0:19:123.5% for whole milk, 1.7% for semi-skimmed,
0:19:12 > 0:19:15and unsurprisingly, 0% for skimmed.
0:19:17 > 0:19:20But the next problem they face is the fat won't mix evenly.
0:19:21 > 0:19:25If you have a lot of raw milk and you leave it for a few hours,
0:19:25 > 0:19:27you're going to have a line on the top.
0:19:27 > 0:19:30We don't want to do that, we want a perfect solution, clear and white.
0:19:32 > 0:19:36To solve this predicament, the next step is homogenisation,
0:19:36 > 0:19:41which became common practice in the late 1980s because consumers
0:19:41 > 0:19:44preferred their milk without a layer of cream on the top.
0:19:45 > 0:19:49The milk is forced through small holes at high pressure,
0:19:49 > 0:19:54smashing the fat globules till they become tiny and dispersed.
0:19:54 > 0:19:56That cream that we used to get on the top of the milk,
0:19:56 > 0:19:58- that doesn't happen anymore. - That's not going to happen.
0:19:58 > 0:20:01The final step is pasteurisation,
0:20:01 > 0:20:05which kills off the majority of bacteria in the milk.
0:20:05 > 0:20:09This is happening on these plates, so what we do here is
0:20:09 > 0:20:14we heat up the milk, up to 74.5 degrees
0:20:14 > 0:20:16and then the milk goes through, very fast,
0:20:16 > 0:20:20through those pipes for 28 seconds
0:20:20 > 0:20:23at 74.5 degrees.
0:20:23 > 0:20:25- And that's pasteurisation. - That's correct.
0:20:28 > 0:20:33Let's see if I can beat the milk in this 55-second process.
0:20:33 > 0:20:35So we've got raw milk here, all right.
0:20:35 > 0:20:40It's flowing through here, then we start to warm it up,
0:20:40 > 0:20:44warm it up through these pipes, down to here where we separate the fat.
0:20:44 > 0:20:48Then we decide whether it's going to be skimmed,
0:20:48 > 0:20:50semi-skimmed or full fat.
0:20:50 > 0:20:53- We start to add the fat back in and then we homogenise it...- Yes.
0:20:53 > 0:20:56..so that we mix all the fat in with the milk
0:20:56 > 0:20:58so that we don't have the fat layer on top of the milk.
0:20:58 > 0:21:01Then we need to pump it back over here.
0:21:06 > 0:21:08- We heat it.- Yes.
0:21:08 > 0:21:09- 78 degrees.- That's correct.
0:21:09 > 0:21:11- 28 seconds.- 74.5.
0:21:11 > 0:21:1574 degrees, 28 seconds, right, then we've pasteurised it.
0:21:15 > 0:21:17Now we've got to chill it so we can use it.
0:21:17 > 0:21:20And that's five degrees and that's over here.
0:21:20 > 0:21:25- All of that in one minute, how did I do?- Very good.
0:21:26 > 0:21:31The Dysons' milk has now moved into a chilled holding tank, to be mixed
0:21:31 > 0:21:35for about 30 minutes before the next stage of its remarkable journey.
0:21:37 > 0:21:39Who knew all that? I most certainly didn't.
0:21:39 > 0:21:43You see a cow, you know it produces milk, you think it goes in a carton.
0:21:43 > 0:21:48I had absolutely no idea how milk goes through so many processes.
0:21:51 > 0:21:54I've seen how pasteurisation, which we take for granted,
0:21:54 > 0:21:57is such a crucial procedure in milk production today.
0:21:59 > 0:22:03And historian Ruth Goodman is discovering how this process
0:22:03 > 0:22:05has saved hundreds of thousands of lives.
0:22:05 > 0:22:08Before the Industrial Revolution,
0:22:08 > 0:22:12most people drank their milk raw, meaning straight from the cow.
0:22:12 > 0:22:14And wherever you lived, you were never very far
0:22:14 > 0:22:16from one of our four-legged friends.
0:22:19 > 0:22:21But all that was about to change with
0:22:21 > 0:22:25the arrival of the Victorians and their incredible machines.
0:22:27 > 0:22:30As Britain steamed ahead towards the late 19th century,
0:22:30 > 0:22:33a network of railways moved milk
0:22:33 > 0:22:36hundreds of miles around the country.
0:22:36 > 0:22:40With the invention of the steam engine, the cows could be out in the
0:22:40 > 0:22:44countryside and we could bring their milk at top speed into the cities.
0:22:50 > 0:22:53It seems a perfect win-win situation,
0:22:53 > 0:22:59but this new efficient distribution method had one fatal consequence
0:22:59 > 0:23:03and that was the spread of bovine tuberculosis, TB.
0:23:08 > 0:23:10In the 19th century,
0:23:10 > 0:23:14tuberculosis was the biggest killer in Western Europe.
0:23:14 > 0:23:17Bovine tuberculosis was a variant that could be
0:23:17 > 0:23:19caught by drinking raw cow's milk.
0:23:21 > 0:23:25And raw cow's milk was being efficiently delivered all over
0:23:25 > 0:23:27the country by rail.
0:23:30 > 0:23:32The problem was one of contamination.
0:23:32 > 0:23:36The milk from a large number of different cows
0:23:36 > 0:23:39was mixed together in churns,
0:23:39 > 0:23:41which increased the risk of infection.
0:23:41 > 0:23:45Peter Atkins, Professor of Geography at Durham University, has been
0:23:45 > 0:23:49looking into how devastating this was for the British population.
0:23:49 > 0:23:51How many people were affected by this?
0:23:51 > 0:23:55In the period that I've been looking at, 1850 to 1960, something
0:23:55 > 0:24:00like 800,000 dying from bovine tuberculosis for Great Britain.
0:24:00 > 0:24:03Because they were drinking more milk than any other
0:24:03 > 0:24:06group in the population, we're talking here about young children.
0:24:06 > 0:24:08If you had milk from that churn,
0:24:08 > 0:24:10it would have been possible to catch tuberculosis
0:24:10 > 0:24:12because of the mixing process.
0:24:14 > 0:24:19In the 1920s, the churns changed to special milk rail tankers
0:24:19 > 0:24:21which were glass-lined for hygiene
0:24:21 > 0:24:23and cork-insulated to keep the milk cool.
0:24:25 > 0:24:27When they moved over to the big tankers,
0:24:27 > 0:24:30you've got lots of milk all being mixed together.
0:24:30 > 0:24:32I mean, this must have made the problem a lot worse?
0:24:32 > 0:24:35From 1926 onwards, that's correct.
0:24:35 > 0:24:40With 1,000 cows, that milk tanker was still infected
0:24:40 > 0:24:43just by one cow that had tuberculosis.
0:24:43 > 0:24:47It's a disease which can be diluted many times over.
0:24:47 > 0:24:52'Back in 1864, scientist Louis Pasteur discovered that
0:24:52 > 0:24:56'heating wine would kill most of the bad bacteria.'
0:24:56 > 0:24:58A pan of hot water.
0:24:58 > 0:25:02'The process was named after the man who invested it -
0:25:02 > 0:25:03'pasteurisation.
0:25:03 > 0:25:08'A method that could be used to kill the tuberculosis microbes in milk.'
0:25:08 > 0:25:12So, this is our unpasteurised milk straight from the cow.
0:25:12 > 0:25:17'It was so simple and effective, we still use this method today.
0:25:17 > 0:25:20'But people in the 1930s and early '40s were very
0:25:20 > 0:25:25'distrustful of this potentially life-saving option.'
0:25:25 > 0:25:28Considering it is such a simple process,
0:25:28 > 0:25:31why do you think people were so reluctant?
0:25:31 > 0:25:32Yes, it's strange, isn't it?
0:25:32 > 0:25:36I think there's some reluctance on the part of the consumers.
0:25:36 > 0:25:39Some of whom think that the ingredients of the milk
0:25:39 > 0:25:42are being damaged, such as the vitamins for instance.
0:25:43 > 0:25:48Incredibly, it wasn't until the 1960s that it became the norm
0:25:48 > 0:25:51to pasteurise milk in the UK. And even to this day,
0:25:51 > 0:25:54it's not compulsory in England and Wales.
0:25:54 > 0:25:58So just a matter of lifting it from the hot water...
0:25:59 > 0:26:00..into the cold.
0:26:01 > 0:26:06The pasteurising of raw milk and the introduction of compulsory
0:26:06 > 0:26:10TB testing in cattle, which eradicated cows with TB,
0:26:10 > 0:26:14reduced the number of cases of human tuberculosis.
0:26:15 > 0:26:21By 1960, most cattle were free of the disease and the risk of
0:26:21 > 0:26:24bovine tuberculosis to the human population
0:26:24 > 0:26:25is now a thing of the past.
0:26:34 > 0:26:36Back in the Aylesbury factory,
0:26:36 > 0:26:40we've just pasteurised our milk on a massive scale.
0:26:40 > 0:26:44Now, over 18 hours and 35 minutes since it left the cow,
0:26:44 > 0:26:47Mario needs to take another sample of milk
0:26:47 > 0:26:49to make sure the processes have worked.
0:26:50 > 0:26:52If this passes the test,
0:26:52 > 0:26:55- this is virtually supermarket-ready milk, right?- Yes, that's correct.
0:26:58 > 0:27:01First up, he is testing that this enormous batch of
0:27:01 > 0:27:05semi-skimmed milk has the correct 1.7% of fat in it.
0:27:05 > 0:27:08On this equipment, this is able to tell me
0:27:08 > 0:27:11how much fat it is in the sample. That was semi-skimmed milk.
0:27:11 > 0:27:15And as you can see on the screen, standardisation passed is correct.
0:27:15 > 0:27:19'Next, he needs to make sure that it's been homogenised correctly.'
0:27:19 > 0:27:22So we just need a single drop of milk.
0:27:22 > 0:27:24'With no signs of fatty lumps.'
0:27:24 > 0:27:28As you can see, the fat globules, all of them
0:27:28 > 0:27:32have got more or less the same size, they're very, very small.
0:27:32 > 0:27:36If you compare the raw milk, the fat globules are big.
0:27:36 > 0:27:40So we can say that the milk has been homogenised properly.
0:27:40 > 0:27:42Now we have one more thing to do,
0:27:42 > 0:27:46we need to taste it and make sure it tastes nice.
0:27:49 > 0:27:53- Yeah, that's the semi-skimmed milk I buy.- There we go.
0:27:54 > 0:27:56With the press of a button,
0:27:56 > 0:28:0098,000 litres of milk is released
0:28:00 > 0:28:03into one of the 12 finished milk silos,
0:28:03 > 0:28:0718 hours, 39 minutes after leaving the cow.
0:28:07 > 0:28:10Do you know what, I can hear it gushing.
0:28:10 > 0:28:14To ensure a constant supply, milk gets stock piled here
0:28:14 > 0:28:17for up to five hours, waiting for its turn to be bottled.
0:28:19 > 0:28:24While I'm being totally gobsmacked by the massive volumes of milk
0:28:24 > 0:28:25processed so quickly,
0:28:25 > 0:28:29Cherry is busy investigating how cheese is made on a mammoth scale.
0:28:32 > 0:28:35While the vast majority of milk ends up in our fridges
0:28:35 > 0:28:38just days after it's left the farm, some spends months,
0:28:38 > 0:28:41if not years, at cheese factories like this one.
0:28:45 > 0:28:47Here in Taw Valley, Devon,
0:28:47 > 0:28:50is one of the largest cheese factories in the UK,
0:28:50 > 0:28:56making an enormous 100 million blocks of cheese a year.
0:28:56 > 0:29:00Rob Whitely, process manager, is going to show me how it's done.
0:29:00 > 0:29:04Wow. What is that smell?
0:29:04 > 0:29:08So that smell is the start of the cheese-making process.
0:29:08 > 0:29:12That is strong. If my eyes start to water, will you let me know?
0:29:12 > 0:29:14I can't smell it, so I must be used to it.
0:29:14 > 0:29:16THEY LAUGH
0:29:16 > 0:29:20So what is going on here? These vats are enormous.
0:29:20 > 0:29:24We've got ten cheese vats here. Predominantly we make cheddar.
0:29:24 > 0:29:25In a year,
0:29:25 > 0:29:29- we will make approximately 37,000 tonnes of cheese.- Wow.
0:29:34 > 0:29:39A million litres of fresh milk comes through this factory every 24 hours.
0:29:44 > 0:29:46Here it comes, wow.
0:29:46 > 0:29:52Oh, my goodness, that is an unfathomable amount of milk.
0:29:52 > 0:29:55They'll be 20,000 litres of milk in this vat.
0:29:55 > 0:29:57Absolutely amazing.
0:29:57 > 0:30:01To make cheese on a monumental scale like this,
0:30:01 > 0:30:05you need a lot of a rather surprising but crucial ingredient.
0:30:05 > 0:30:08Once we've started putting the milk into the bottom of the vat,
0:30:08 > 0:30:12we then need to add the bacteria to start producing acid in the cheese.
0:30:12 > 0:30:17These good bacteria feed on milk sugars called lactose
0:30:17 > 0:30:20and transform it into lactic acid.
0:30:21 > 0:30:24And we isolate particular strains depending on what
0:30:24 > 0:30:26characteristic we want in the end cheese.
0:30:26 > 0:30:28A bit like when you're making a curry
0:30:28 > 0:30:30- and you use spices to flavour it? - Yes.
0:30:30 > 0:30:33- That's how you use bacteria? - Exactly like that.
0:30:33 > 0:30:36- Like a chef? - It's like being a cheese chef.
0:30:36 > 0:30:40And it's the bacteria that these chefs use that determine
0:30:40 > 0:30:43the characteristics and flavour of a good cheese.
0:30:43 > 0:30:45- All in.- Excellent.
0:30:50 > 0:30:54Now the process of producing cheddar on an epic scale
0:30:54 > 0:30:55can continue.
0:30:57 > 0:31:00A milk-clotting enzyme called rennet is added.
0:31:00 > 0:31:04This, together with the lactic acid, helps to separate the milk
0:31:04 > 0:31:07solids, called curds, from the liquid, known as whey.
0:31:11 > 0:31:13So this is where we see the curds and whey.
0:31:13 > 0:31:18Oh, whoa, eugh! Eugh, that's like scrambled eggs.
0:31:18 > 0:31:22- What we can do is take some out and show you.- Oh, it's warm.
0:31:24 > 0:31:29It's like porridge and scrambled eggs, that's extraordinary.
0:31:30 > 0:31:33The whey is then drained off, leaving the curd
0:31:33 > 0:31:37which is heated and stirred to squeeze out yet more whey.
0:31:37 > 0:31:41The massive curd is formed into huge slabs.
0:31:53 > 0:31:55Oh, wow.
0:31:57 > 0:32:01All this time the bacteria have been feeding on lactose in the milk,
0:32:01 > 0:32:04but now they need to be controlled.
0:32:04 > 0:32:09So we add salt to then arrest the action of the bacteria.
0:32:09 > 0:32:12Because if we let the bacteria continue, they would actually
0:32:12 > 0:32:13destroy the cheese.
0:32:13 > 0:32:15We don't want that to happen.
0:32:15 > 0:32:18We want to close them down, they've had a bit of a party,
0:32:18 > 0:32:20now it's time for them to wind down a bit.
0:32:25 > 0:32:28Finally, the salted curd is compressed into blocks,
0:32:28 > 0:32:32vacuum-packed for protection and ready for maturing.
0:32:34 > 0:32:39400 years ago, cheese makers stored cheddar in caves, which are always
0:32:39 > 0:32:44cool with high humidity, ideal to stop the cheeses drying out.
0:32:44 > 0:32:46Some cheeses are still matured that way.
0:32:48 > 0:32:52But here, next door to the factory, there's a controlled maturing
0:32:52 > 0:32:56warehouse, which is kept at a constant ten degrees Centigrade.
0:32:58 > 0:33:04There are over 28,000 tonnes of cheese ripening at any one time,
0:33:04 > 0:33:07worth over £150 million.
0:33:07 > 0:33:12Is it only the expensive artisan cheese that is matured?
0:33:12 > 0:33:14Absolutely not, all our cheese has to be matured.
0:33:14 > 0:33:18When it comes from the production area, it's actually curd, and that
0:33:18 > 0:33:21curd needs to be broken down into cheese particles that we can eat.
0:33:23 > 0:33:26A standard cheddar will take around six months to mature,
0:33:26 > 0:33:30but it's Colin's job to work out which cheese can ripen and
0:33:30 > 0:33:35improve its flavour over the next 18 to 24 months, to become extra mature
0:33:35 > 0:33:39and he wants to see if I can tell which cheese has that potential.
0:33:42 > 0:33:44So what am I looking out for in the taste?
0:33:44 > 0:33:49- You're looking for a nice clean flavour, buttery, smooth.- Mmm.
0:33:49 > 0:33:53And that makes it have the potential to mature into an extra mature.
0:33:53 > 0:33:56OK, I've tried that one, it's delicious.
0:33:56 > 0:33:59This one's three months older than the previous one.
0:33:59 > 0:34:04That tastes a little more bitter. A little less creamy.
0:34:04 > 0:34:06- Yeah.- I mean, it's so subtle.
0:34:06 > 0:34:07- And you're right.- Really?
0:34:07 > 0:34:10That was the poor one, the one that's not going to make the grade,
0:34:10 > 0:34:13- so that one's going to be sold now. - So I'd selected the correct one,
0:34:13 > 0:34:15does that mean that I get a job here?
0:34:15 > 0:34:16You get the job.
0:34:16 > 0:34:20Tasting cheese all day. I am happy as Larry.
0:34:30 > 0:34:32Back at the dairy factory,
0:34:32 > 0:34:35the next vital stage for our milk is for it to be bottled.
0:34:37 > 0:34:4240,000 plastic bottles an hour are blow-moulded in a process
0:34:42 > 0:34:45so secret that it has to be kept from competitors,
0:34:45 > 0:34:47so I'm not allowed to see it.
0:34:47 > 0:34:51And there's no point making them somewhere else, you'd just be
0:34:51 > 0:34:55transporting air, so they're made here in a factory on site.
0:34:55 > 0:34:58A million bottles a day.
0:35:01 > 0:35:04Once they're created, the empty bottles are transported
0:35:04 > 0:35:05to the colossal filling hall.
0:35:14 > 0:35:17It's the size of the pitch at Wembley Stadium,
0:35:17 > 0:35:19containing six filling lines.
0:35:21 > 0:35:24Brilliant! All of a sudden, it's got milk in it.
0:35:26 > 0:35:31Up until now, milk has just been in vast volumes that I can't compute.
0:35:31 > 0:35:35Now I can see a bottle that I buy.
0:35:37 > 0:35:39And in this highly-automated world,
0:35:39 > 0:35:44the only guy I can find here is Miles Lord, production team leader.
0:35:44 > 0:35:46Do you know how fast this is going?
0:35:46 > 0:35:50Well, this filler now is running at 17,000 bottles an hour.
0:35:50 > 0:35:52Which is the same as 4.7 a second.
0:35:52 > 0:35:54Nearly five bottles a second?
0:35:54 > 0:35:57Nearly five bottles a second. There's three stages to the filling.
0:35:57 > 0:36:00When it first comes in, it runs at a slower rate
0:36:00 > 0:36:02and that stops it splashing up and foaming.
0:36:02 > 0:36:06Then the speed increases, we put more in.
0:36:06 > 0:36:08And the last bit, we slow that right down again
0:36:08 > 0:36:10just so it doesn't foam at the top.
0:36:10 > 0:36:11And that's how I pour my beer.
0:36:11 > 0:36:13Exactly.
0:36:13 > 0:36:15It's got to keep moving, hasn't it?
0:36:15 > 0:36:18If we have the line standing for 20 minutes, we've got
0:36:18 > 0:36:20to get rid of the milk that's on the line.
0:36:20 > 0:36:24Just 23 hours and 56 minutes after leaving the cow,
0:36:24 > 0:36:27I can watch our milk get bottled,
0:36:27 > 0:36:30although it can take up to 48 hours to reach this point.
0:36:31 > 0:36:33What's happening now?
0:36:33 > 0:36:35We've filled the bottle up and within seconds,
0:36:35 > 0:36:39within point-seconds, we put a cap on it.
0:36:39 > 0:36:43I can't think of anything worse than milk dripping all over my shopping.
0:36:43 > 0:36:45How can you guarantee that that lid is on?
0:36:45 > 0:36:48Everything we do is checked at every stage
0:36:48 > 0:36:50to make sure that the milk is fine.
0:36:50 > 0:36:54We have a camera, it's looking at every single bottle that goes out
0:36:54 > 0:36:57and it's saying, "Is that in the right place?"
0:36:57 > 0:36:59And what happens if it's not?
0:36:59 > 0:37:01If it's not, it'll reject it.
0:37:01 > 0:37:04Can we put one on there isn't right and see what happens?
0:37:04 > 0:37:06We can.
0:37:06 > 0:37:10To test the camera, we've taken the foil seal off and replaced the lid.
0:37:13 > 0:37:14So it should be spotting it.
0:37:16 > 0:37:20MACHINE BEEPS GREGG CHEERS
0:37:20 > 0:37:22There you go, that's our bottle.
0:37:26 > 0:37:28Do you load it into these cartons of milk?
0:37:28 > 0:37:30- We don't do that here, no.- Good. - Do you not like those?
0:37:30 > 0:37:33- No, the whole nation hates them. - OK, yeah.- This is what we want.
0:37:33 > 0:37:36You can open that and not end up with it over your jumper.
0:37:36 > 0:37:38Yeah, absolutely, hopefully.
0:37:41 > 0:37:45While I'm bowled over at the scale of bottled milk produced here,
0:37:45 > 0:37:48Arla makes another product on a mammoth scale that gets
0:37:48 > 0:37:49spread on our toast every morning.
0:37:52 > 0:37:56The co-operative produces 43% of the UK's butter.
0:37:56 > 0:37:59And Ruth is retracing the steps of Victorian dairy maids
0:37:59 > 0:38:02to discover just how butter used to be made.
0:38:07 > 0:38:11Before refrigeration, milk went sour very quickly,
0:38:11 > 0:38:14so farmers had to come up with ways not to waste it.
0:38:15 > 0:38:18The answer - turn it into butter.
0:38:18 > 0:38:22But it was hard physical labour, and as it was considered indoor work,
0:38:22 > 0:38:26mostly a job for dairy maids, many as young as 13.
0:38:28 > 0:38:31A maid might have to milk as many as ten cows in the morning
0:38:31 > 0:38:35before she could even start making the butter.
0:38:35 > 0:38:38That's about two and a half hours' work before you've even begun.
0:38:39 > 0:38:43On this working Victorian farm in Shropshire,
0:38:43 > 0:38:46Ingrid Hartung keeps traditional techniques alive.
0:38:46 > 0:38:50She chills milk in cool water to make the cream rise to the top
0:38:50 > 0:38:52and skims it off to make butter.
0:38:56 > 0:39:00So there it is, our lovely cream.
0:39:00 > 0:39:03And then, of course, from this we make yellow butter.
0:39:03 > 0:39:05That's right. In the spring/summer,
0:39:05 > 0:39:09it is actually a nice yellow, rich colour because, of course,
0:39:09 > 0:39:12the natural ingredients that the cows are eating when they're grazing
0:39:12 > 0:39:15outside makes a nice yellow colour.
0:39:15 > 0:39:20Although grass looks green, there's actually a yellow/orange
0:39:20 > 0:39:25chemical called beta carotene found in every mouthful a cow eats.
0:39:25 > 0:39:28In winter, when the cows eat less grass,
0:39:28 > 0:39:30they produce a much paler butter
0:39:30 > 0:39:33which is less appealing to consumers.
0:39:33 > 0:39:36So here we are trying to do this in the middle of winter,
0:39:36 > 0:39:39- which is, erm, challenging. - Challenging, yes.
0:39:39 > 0:39:43So dairy maids came up with an ingenious solution to produce
0:39:43 > 0:39:45just the right shade of yellow.
0:39:45 > 0:39:50We substitute the carotene that the cows would eat in the grass
0:39:50 > 0:39:52with a good old-fashioned carrot.
0:39:56 > 0:39:59Just put a little bit and see what colour.
0:40:00 > 0:40:03Not very much but there we go, we don't want to overdo it.
0:40:06 > 0:40:10We're now ready for the hard graft of making butter.
0:40:10 > 0:40:13Now, if we've got everything absolutely perfect
0:40:13 > 0:40:16and the cream's top quality and the temperatures are perfect,
0:40:16 > 0:40:20we could expect this cream to turn in what? 20 minutes?
0:40:20 > 0:40:23If it cools down a bit, half an hour, but something like that, yes.
0:40:23 > 0:40:26The cream needs to be shaken enough
0:40:26 > 0:40:30so that the fat in it clumps together to make butter.
0:40:30 > 0:40:33And if we've got it all wrong we could be here...?
0:40:33 > 0:40:34Two hours plus.
0:40:34 > 0:40:36THEY LAUGH
0:40:36 > 0:40:39We'll take turns. Go on, you get started.
0:40:43 > 0:40:47'Unlike a lot of jobs for women at the time, dairy work was well paid,
0:40:47 > 0:40:51'but you had to have very strong shoulders and arms.'
0:40:51 > 0:40:53So shall I take over for a bit?
0:40:53 > 0:40:55Yes, if you want to, that would be very good.
0:40:55 > 0:40:58'Using a much larger churn, a really brawny dairy maid could
0:40:58 > 0:41:01'make 20 or 30lb of butter in one go.'
0:41:01 > 0:41:03So let's just have a little look.
0:41:03 > 0:41:06'After churning until my arms ache, I'm starting to realise what
0:41:06 > 0:41:09'a difficult job being a dairy maid would have been.
0:41:09 > 0:41:13'17 pints of milk yields only a pound of butter.
0:41:15 > 0:41:18'In my case, no butter at all.
0:41:18 > 0:41:20'So far, it's just really thick cream.'
0:41:27 > 0:41:32So we are hitting two and a half hours and it's still not come.
0:41:32 > 0:41:34- Yeah.- I mean, this can happen, can't it?- Yeah.
0:41:34 > 0:41:37If the weather's difficult and the cold...
0:41:37 > 0:41:38Sometimes it's the cream,
0:41:38 > 0:41:42but at this time of year, it's more likely to be the cold, yeah.
0:41:42 > 0:41:46Despite butter being best kept in the fridge,
0:41:46 > 0:41:50ideally it needs room temperature for the fats to solidify.
0:41:50 > 0:41:53So here, in the freezing temperatures of the dairy,
0:41:53 > 0:41:55we're having trouble.
0:41:55 > 0:41:57It's very disappointing,
0:41:57 > 0:42:01- but luckily you had got a batch you'd already done.- Yes.
0:42:01 > 0:42:03THEY LAUGH
0:42:03 > 0:42:05Once the butter was formed, any dairy maid worth her salt
0:42:05 > 0:42:08would shape a design as a trademark.
0:42:10 > 0:42:14There are all kinds of different patterns that you can just do
0:42:14 > 0:42:16with the butter pats.
0:42:16 > 0:42:18That's a single wheat sheaf.
0:42:18 > 0:42:22Hand-crafted butter became far less common after mechanisation
0:42:22 > 0:42:26was gradually introduced during the 19th century.
0:42:28 > 0:42:31Today, automatic churns have almost entirely replaced
0:42:31 > 0:42:33the muscles of dairy maids.
0:42:37 > 0:42:41But our love affair with creamy butter still continues.
0:42:48 > 0:42:50Back at the dairy factory,
0:42:50 > 0:42:55it's taken our milk just under 24 hours to get into a bottle.
0:42:55 > 0:42:57Now the bottles are put onto trolleys
0:42:57 > 0:43:00and are heading for distribution to our grocery shelf.
0:43:03 > 0:43:06We've just packed up this milk the other side of that wall.
0:43:06 > 0:43:10Traditionally, in this hall would have been hundreds of people,
0:43:10 > 0:43:13but here they like to do things a little differently.
0:43:15 > 0:43:19MUSIC: Robot Rock by Daft Punk
0:43:24 > 0:43:27This is the only place in the UK
0:43:27 > 0:43:30where futuristic robots like these distribute milk.
0:43:38 > 0:43:41In this custom-built, enormous fridge
0:43:41 > 0:43:4575 state-of-the-art robots transport all this from the filling zone
0:43:45 > 0:43:47to the distribution bays
0:43:47 > 0:43:49to send on to supermarkets nationwide.
0:43:52 > 0:43:56They shift 1.5 million litres of milk per day,
0:43:56 > 0:44:00enough to provide daily milk to Greater Manchester, Somerset
0:44:00 > 0:44:03and the West Midlands combined.
0:44:03 > 0:44:06I've never seen anything like this ever.
0:44:06 > 0:44:07This looks nuts to me.
0:44:11 > 0:44:15Dispatch team leader, Paul Ansell, is a robot expert.
0:44:15 > 0:44:17Somebody is controlling these robots, are they?
0:44:17 > 0:44:20I mean they're not thinking for themselves?
0:44:20 > 0:44:22It's not a human that controls the robots, they're controlled
0:44:22 > 0:44:25by the warehouse management system that's in the fridge.
0:44:25 > 0:44:28When the milk comes through the door, there's an RFID,
0:44:28 > 0:44:32a radio frequency identification number that goes to each trolley,
0:44:32 > 0:44:35and then the robots will move or action their moves around the fridge.
0:44:35 > 0:44:37With robots running backwards and forwards,
0:44:37 > 0:44:39you must have to be careful where you stand.
0:44:39 > 0:44:41Not really, it's got the sensor in front.
0:44:41 > 0:44:45The laser's always looking in front of it at any given time.
0:44:46 > 0:44:48I'm going to test out the robot's
0:44:48 > 0:44:51laser beam collision avoidance device.
0:44:53 > 0:44:56Whoa, whoa, whoa, whoa.
0:44:57 > 0:45:00HE LAUGHS
0:45:00 > 0:45:02That's just nuts.
0:45:02 > 0:45:04You could actually take your robot for a walk.
0:45:04 > 0:45:06Come on, come on. Come on, then.
0:45:08 > 0:45:09Stop.
0:45:09 > 0:45:10Good boy.
0:45:16 > 0:45:18And off she goes.
0:45:20 > 0:45:22After 35 miles of work
0:45:22 > 0:45:25these robots know to automatically dock
0:45:25 > 0:45:27and charge their lithium batteries.
0:45:29 > 0:45:31It goes and puts its feet up and has a cup of tea.
0:45:31 > 0:45:33It puts itself on charge.
0:45:33 > 0:45:36If you didn't have the robots here, you'd need people.
0:45:36 > 0:45:38How many people would you need?
0:45:38 > 0:45:41Somewhere in the region of 300 people in this fridge alone.
0:45:41 > 0:45:44I've been in this business 18 years now.
0:45:44 > 0:45:47So, I started in a fridge, I effectively was a robot.
0:45:47 > 0:45:51You have to think each trolley weighs about 240 kilos, if you're
0:45:51 > 0:45:55doing that for a 12-hour shift, it's very, very labour intensive.
0:45:55 > 0:45:57- So a robot never phones in sick.- No.
0:45:57 > 0:45:59- Never takes a tea break when he shouldn't be.- No.
0:45:59 > 0:46:01But you can't talk to a robot about football on a Monday.
0:46:01 > 0:46:03You could try but you wouldn't get an answer back.
0:46:06 > 0:46:09Robots haven't just taken control in this spectrum.
0:46:09 > 0:46:13Out on the farms, there is a robotic revolution going on.
0:46:18 > 0:46:23In the heart of the Lancashire countryside is a scene
0:46:23 > 0:46:25that could be from science fiction.
0:46:28 > 0:46:33On a dairy farm in Blackburn the cows are in control.
0:46:34 > 0:46:40MUSIC: Thus Spake Zarathustra by Richard Strauss
0:46:41 > 0:46:44This is a state-of-the-art Merlin.
0:46:50 > 0:46:54An automatic, laser-guided, milking robot.
0:46:57 > 0:47:02Machines like these are being used in about 5% of farms in the UK
0:47:02 > 0:47:05and the cows can choose to use them whenever they want.
0:47:09 > 0:47:13Chris Bargh installed his three milking robots six years ago.
0:47:13 > 0:47:18His herd of 180 cows choose to milk themselves three times a day,
0:47:18 > 0:47:21producing 5,000 litres.
0:47:21 > 0:47:24- The cows come in when they want to be milked.- Yeah.
0:47:24 > 0:47:26- And they get milked by robots.- Yes.
0:47:26 > 0:47:28The cows actually come and milk themselves
0:47:28 > 0:47:30whenever they want to be milked.
0:47:30 > 0:47:33It's all robotic milking now. It's absolutely amazing.
0:47:33 > 0:47:35That cow can't wait to get in.
0:47:35 > 0:47:37Can't wait to get in, no.
0:47:37 > 0:47:39So they're actually queuing up to get in there.
0:47:39 > 0:47:42Yeah, no, they just come in and queue up whenever.
0:47:42 > 0:47:46And the clever cows will look to see which has the shortest queue.
0:47:51 > 0:47:54With the cow in position, it's time for the robot to get to work.
0:47:56 > 0:47:59So you'll see now as the brushes come round...
0:47:59 > 0:48:01and they go round and clean the teats.
0:48:02 > 0:48:04Oh, my word.
0:48:04 > 0:48:07And then you'll see the lasers start flashing on the teats now.
0:48:07 > 0:48:09Oh, yeah. Yeah, yeah, yeah, yeah.
0:48:09 > 0:48:13Yeah, so now it's pinpointing exactly where them teats are.
0:48:13 > 0:48:15- Oh, it's going... - Yeah, it's got it, it's got it.
0:48:17 > 0:48:19These robots are working 24 hours a day.
0:48:19 > 0:48:20They never stop, yeah.
0:48:20 > 0:48:23- The cows can be milked whenever they want.- Yes.
0:48:23 > 0:48:27So the cows coming out now, anybody that's used the public transport
0:48:27 > 0:48:29in London will recognise this, I think.
0:48:29 > 0:48:32- You put your ticket in, the barrier moves.- Yeah.
0:48:32 > 0:48:34Now how does the robot know which cow it's got?
0:48:34 > 0:48:38Every cow has a little ear tag - a little transponder in its ear -
0:48:38 > 0:48:40and that's measured on the robot.
0:48:42 > 0:48:47Chris' robots can record almost every aspect of his herd, from each
0:48:47 > 0:48:51cow's exact diet, to the amount of fat, protein and sugar in the milk.
0:48:53 > 0:48:58When I was a lad, I was still milking conventionally, that had to be sent
0:48:58 > 0:49:02away to a laboratory once a month to be able to get that information.
0:49:02 > 0:49:04Now, every single time that cow's milked,
0:49:04 > 0:49:06we know that information.
0:49:11 > 0:49:14Merlin needs to be strong enough to cope with the weight of a
0:49:14 > 0:49:18full-size cow, which can be as heavy as 11 men,
0:49:18 > 0:49:22but it also needs to be gentle enough for milking.
0:49:22 > 0:49:27The robot can make tiny adjustments to the squeeze on the cow's teat
0:49:27 > 0:49:30so it feels even gentler than a calf's mouth.
0:49:32 > 0:49:34The first robots were introduced in the '90s,
0:49:34 > 0:49:37but more recently the technology has advanced
0:49:37 > 0:49:42and now about 30% of new milking systems in the UK are robotic.
0:49:43 > 0:49:45But what happens if it goes wrong?
0:49:47 > 0:49:50If the same fault happened with three cows on the trot,
0:49:50 > 0:49:55the whole robot shuts itself down and rings my mobile phone
0:49:55 > 0:49:57to tell me there's a breakdown.
0:49:57 > 0:50:00And the use of technology goes way beyond milking.
0:50:00 > 0:50:04It can even offer a calming back rub to keep the cows contented.
0:50:06 > 0:50:10Aren't we missing out here on the human interaction between you,
0:50:10 > 0:50:12the farmer, and the cow?
0:50:12 > 0:50:14We see the character of these cows so much more now,
0:50:14 > 0:50:16because we're not forcing 'em.
0:50:16 > 0:50:19Because humans aren't really telling them to do anything.
0:50:19 > 0:50:21Yeah. They're relaxed and chilled.
0:50:21 > 0:50:25We've had the robots in six years now, and when we first put them in,
0:50:25 > 0:50:28everyone was a little bit nervous. Oooh, robotic milking the cows.
0:50:28 > 0:50:31Some of the older cows wouldn't change their ways.
0:50:31 > 0:50:3680% of the herd have never seen a standard parlour,
0:50:36 > 0:50:39they just assume that milking is done like this and always has been.
0:50:39 > 0:50:41Mate, I love this. I absolutely love this.
0:50:41 > 0:50:45Well, listen, I'm not a farmer, but they look pretty happy to me
0:50:45 > 0:50:48and they're wandering in of their own accord, no doubt about that.
0:50:48 > 0:50:51These cows want to be in there, they want to be milked.
0:50:51 > 0:50:52- I can tell you that.- Yes.
0:50:56 > 0:51:00These are happy cows and the milk yields are up.
0:51:00 > 0:51:02This could well be the future.
0:51:07 > 0:51:09While Gregg has seen the future of milking,
0:51:09 > 0:51:12I've come to a factory in Gloucester to see how milk is
0:51:12 > 0:51:16turned into one of the most decadent products of all.
0:51:18 > 0:51:21This tanker contains 28 tonnes of milk,
0:51:21 > 0:51:26and at this factory they get through around six of them a week.
0:51:31 > 0:51:35This factory is an ice cream lover's delight.
0:51:35 > 0:51:38Brian Field is the quality assurance manager.
0:51:38 > 0:51:41Why is milk so important to ice cream?
0:51:41 > 0:51:44Milk is one of the fundamental ingredients
0:51:44 > 0:51:48from which ice cream is made. All our ice cream recipes use milk.
0:51:48 > 0:51:53We use whole milk, we use cream, we use concentrated milk
0:51:53 > 0:51:55and we use milk powder.
0:51:56 > 0:52:01Brian takes me to where it all starts, the mix department.
0:52:01 > 0:52:03Whoa, oh, my goodness!
0:52:03 > 0:52:04There's the ice cream mix.
0:52:06 > 0:52:08That smells amazing.
0:52:08 > 0:52:10We add our milk, our sugar and our water,
0:52:10 > 0:52:13blend it all together to make the ice cream mix.
0:52:13 > 0:52:16Once that's done, we add some vanilla essence.
0:52:16 > 0:52:20'Each vat holds four tonnes of milk
0:52:20 > 0:52:22'and normally needs 4kg of vanilla essence.'
0:52:22 > 0:52:24- There we go.- Perfect.
0:52:24 > 0:52:26What will this become?
0:52:26 > 0:52:28- This will become Magnum. - Really?- Yeah.
0:52:28 > 0:52:31- So this will contribute... - This is the centre of Magnum.
0:52:31 > 0:52:33This is my greatest dream,
0:52:33 > 0:52:37I can't believe I'm at the centre of an ice cream.
0:52:37 > 0:52:39Once the ingredients are combined, they're pasteurised
0:52:39 > 0:52:43and then the mix makes its way to the factory floors.
0:52:43 > 0:52:46Greg Barrett is the production labour manager.
0:52:46 > 0:52:50From the mix department, the mix is pumped over to these freezers.
0:52:50 > 0:52:52- Yes.- And in these freezers
0:52:52 > 0:52:55it's almost whisked like an egg to minus-six.
0:52:57 > 0:53:01At this point, a vital ingredient is added - air -
0:53:01 > 0:53:04which, believe it or not, makes up half of ice cream.
0:53:04 > 0:53:07And the more air, the softer the ice cream.
0:53:08 > 0:53:11As you can see there, the stick is put in it.
0:53:11 > 0:53:15An ice cream at minus-six degrees is quite pliable.
0:53:15 > 0:53:16Oh, wow.
0:53:16 > 0:53:17As you can see by that.
0:53:17 > 0:53:20So it's still very soft at this stage.
0:53:20 > 0:53:24Yes, we've got to get it quickly hardened into a hardening tunnel.
0:53:24 > 0:53:28It then comes out the other side and it's that hard it's almost brittle.
0:53:30 > 0:53:35In this hardening tunnel the ice creams are blast frozen.
0:53:35 > 0:53:39This ultra-fast freezing creates tiny ice crystals in the mix.
0:53:39 > 0:53:41The smaller the crystals,
0:53:41 > 0:53:44the smoother the texture of the ice cream.
0:53:44 > 0:53:48And as you can tell, it's very, very brittle.
0:53:48 > 0:53:50- I mean, it's rock hard. - Rock hard, yeah.
0:53:50 > 0:53:51Absolutely rock hard.
0:53:51 > 0:53:53Now we dip it in the chocolate.
0:53:53 > 0:53:56But if the chocolate is hot, I presume ...
0:53:56 > 0:53:58Yes, it's plus-44 degrees.
0:53:58 > 0:54:01Then when you dip that in, surely the ice cream will melt.
0:54:01 > 0:54:04No, it won't melt because it's been in the hardening tunnel
0:54:04 > 0:54:09for half an hour approximately, at minus-40 degrees.
0:54:09 > 0:54:12And now the ultimate ice cream experience,
0:54:12 > 0:54:17the frozen vanilla ice cream is coated in warm Belgian chocolate.
0:54:17 > 0:54:22MUSIC: L'amour Est Un Oiseau Rebelle by Georges Bizet
0:54:26 > 0:54:29That may be the most beautiful thing I've ever seen.
0:54:29 > 0:54:31That is pure decadence.
0:54:31 > 0:54:32Absolutely amazing.
0:54:37 > 0:54:42The chocolate-coated ice creams are wrapped, boxed and packed,
0:54:42 > 0:54:44ready for cold storage and distribution.
0:54:45 > 0:54:49To fulfil our boundless love of ice cream
0:54:49 > 0:54:51this factory runs 24/7,
0:54:51 > 0:54:55making 10 million Magnums and 5 million Cornettos a week,
0:54:55 > 0:54:58as well as many other lines,
0:54:58 > 0:55:03producing over 1.4 billion pieces of ice cream every year.
0:55:03 > 0:55:05Not bad when you think the core ingredient is milk.
0:55:20 > 0:55:24At the dairy factory distribution hall, there is good news.
0:55:24 > 0:55:27Robots haven't taken over completely
0:55:27 > 0:55:31and dispatch manager Mark Burrows is showing me why.
0:55:31 > 0:55:34If the customer is ordering anything other than a full trolley,
0:55:34 > 0:55:37we then have to pick that by hand.
0:55:37 > 0:55:39- So let's say there's a 100 in there. - Yes.
0:55:39 > 0:55:42If the supermarket orders 103, we have to pick up three.
0:55:42 > 0:55:44We do, yeah. Slip those over your ears.
0:55:46 > 0:55:48I might have spoken too soon.
0:55:48 > 0:55:49Put this round your waist.
0:55:49 > 0:55:52It looks like computers are in control after all...
0:55:53 > 0:55:55'Talk now, say "ready".'
0:55:55 > 0:55:56..as they're giving the orders.
0:55:56 > 0:55:58Just give it the command "ready".
0:55:58 > 0:56:02- Ready.- 'Scan destination'
0:56:02 > 0:56:04Scan destination.
0:56:04 > 0:56:07So you need to scan the RFID tag.
0:56:08 > 0:56:10You'll hear it vibrate,
0:56:10 > 0:56:13so it knows exactly what product's on that trolley now.
0:56:13 > 0:56:17'Material description - Asda four pint semi.'
0:56:17 > 0:56:21- Asda four pint semi.- 'Pick 60.'
0:56:21 > 0:56:24Pick 60. Oh, crying out loud.
0:56:24 > 0:56:26Right, so I need 60 of those.
0:56:31 > 0:56:33This is hard work.
0:56:33 > 0:56:35After my brief training,
0:56:35 > 0:56:39I am responsible for getting the Weston-Super-Mare order right.
0:56:39 > 0:56:42'Material description - Cravendale two litres.'
0:56:42 > 0:56:45Cravendale two litre. Four.
0:56:47 > 0:56:49'Material description - organic semi.'
0:56:49 > 0:56:51Ready.
0:56:53 > 0:56:55- Two pints.- 'Pick 20.'
0:56:55 > 0:56:56I'm stuck.
0:56:59 > 0:57:03The milk I've just collected needs help to get to the loading bay.
0:57:03 > 0:57:06Juliet Echo Bravo.
0:57:06 > 0:57:08'Juliet Echo Bravo.'
0:57:10 > 0:57:12- Is that our robot? - That's our robot, yeah.
0:57:14 > 0:57:16Off to Weston-Super-Mare.
0:57:16 > 0:57:18Off to Weston-Super-Mare.
0:57:20 > 0:57:23Somebody's going to get our milk tomorrow morning.
0:57:25 > 0:57:28The milk I've just hand-picked is about to be
0:57:28 > 0:57:31one of the 400 deliveries made every day.
0:57:31 > 0:57:35This is the last stage, it's on its way to Weston-Super-Mare.
0:57:35 > 0:57:38It's going to be on someone's breakfast cereal tomorrow morning.
0:57:38 > 0:57:40Come on, boys.
0:57:42 > 0:57:43I have regularly walked into a shop
0:57:43 > 0:57:46and just grabbed a bottle of milk, whether it be the corner shop or
0:57:46 > 0:57:49the supermarket, I've never thought about where it comes from. I just
0:57:49 > 0:57:53take it for granted it's going to be there and it's going to be safe.
0:57:53 > 0:57:56I've followed the milk now all the way from the cow,
0:57:56 > 0:57:59all the way through every single process,
0:57:59 > 0:58:02through all the testing, the bottling, the unbelievable
0:58:02 > 0:58:06amount of people and technology that goes in to making it
0:58:06 > 0:58:11possible for me and you to grab a bottle of milk whenever we want.
0:58:11 > 0:58:13Incredible story.