Episode 1 Wonderstuff


Episode 1

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This series is about all the stuff we can't live without.

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Whether it's products for personal hygiene, home cleaning or even DIY.

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It's about those bottles, cans, sprays, jars and tubes

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crammed into our cupboards, drawers, handbags, sheds and cars.

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I want to know, what's in all this stuff?

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'I'm Jane Moore and I've been handed the ultimate dream ticket -

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'the chance to pull apart some of the most essential items on my everyday shopping list

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'and zero on precisely what's in them that makes them work.'

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We're just in a flush cycle now.

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'It's a mission that's set to take me right out of my comfort zone.'

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Oh, God! I can't bear it.

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'One which demands that I get intimate with an army of boffins and some mind-blowing science.'

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Well, that worked(!)

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'I might've bunked off chemistry at school,

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'but I know I can trust my nose when it comes to sniffing out the facts.'

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I'm going to retch.

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'Yes, I'm hunting for the wonderstuff

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'that holds our lives together.'

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'This time, I fling open the bathroom cabinet

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'to find the wonderstuffs we all rely on to stay preened and cleaned.'

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There are four things in what supermarkets call the "personal care aisle"

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that I buy more than anything else.

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That's soap, shampoo, conditioner and toothpaste.

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My challenge is to go behind the labels

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and discover the magic ingredients that keep us clean.

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Later on in the programme, I'll get my hands on the wonderstuffs at the heart of hair conditioner.

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As peaks go, it's like a molehill up against Mount Everest.

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Absolutely.

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And toothpaste.

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It doesn't have much foaming action.

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It has no foaming action.

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It has gravel action is what it has.

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But before all that, I want to get the low-down

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on what has to be the ultimate bathroom essential - soap.

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As a nation, we use over 100,000 metric tons of soap every year.

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The story of what makes it so good at getting us clean

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will take me back 5,000 years.

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My new best friend, material scientist Dr Mark Miodownik,

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reckons he can show me what makes soap so hard to beat when it comes to personal hygiene,

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by creating some much as our ancestors knew it.

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We'll have a go at cooking up some soap, made to the original recipe.

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Hi, Mark. Just a hotdog for me, thanks.

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We'll eat later.

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I thought first we could try and make soap the old-fashioned way.

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The way it's been made for thousands of years before the modern era.

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Mark is going to conjure up soap from two ingredients

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that would've been a basic part of life for our ancestors.

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So we're going to take fat, which is just normal fat, lard,

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and we're going to add an alkali to it, which we'll make from wood ash.

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This is something that our ancestors really valued.

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It was very important for their crops but also, it turns out, to make soap.

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How do you think they discovered this?

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It's been around for 5,000 years.

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It was probably because people were roasting meat over the fire

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and it was dripping down, the fat, from the meat

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and mixing with the ashes and making soap.

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-People must've picked it out of the fire the next day and thought...

-"I'll do this!"

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In fact, the word alkali is the Arabic for "from ashes".

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Let's see if Mark can recreate

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this most fundamental of chemistry miracles.

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The ashes Mark has collected from the fire are added to water

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to create something called caustic hot ash,

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a strong alkali at the other end of the pH scale to an acid...

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he tells me.

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What we're doing is getting the liquid, the water,

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to dissolve out the active ingredient in here.

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It'll dissolve into the water

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and in a minute, we'll see it clearing

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and there'll be this brownish, muckish water,

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which is exactly perfect.

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-There we are. Nicely plunged.

-Yes.

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I'll show you something from your past,

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which will probably make you fearful.

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It's not one of my ex-boyfriends, is it?

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It's worse! It's litmus paper!

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From your chemistry lessons of old.

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Do you remember how to tell if something is acidic or alkali?

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It goes blue if it's an alkali, red if it's an acid.

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If this is an alkali, this piece of paper should go blue.

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That's properly blue.

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That is victory for us and for our ancestors.

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That means if we take that liquid and add it to some fat,

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we're going to get soap.

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Our pot ash solution is very dilute

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so we need to boil it on the hob to make the alkali more concentrated.

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'Next step is to melt down the fat.

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'It's nothing more complicated than good, old lard.'

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I feel like Delia Smith.

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'Our pot ash soup is now a nice, dark brown gunk,

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'ready to go into the melted fat.

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'Personally, I'll be amazed if we can make soap from this.'

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Enter the alkali!

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'This is what's known in the trade as saponification,

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'literally soap-making.

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'Something's definitely happening.'

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It looks like an atomic cloud.

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We've made a reaction between the fat and the alkali.

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-Can you see what's happening?

-Yeah.

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That is soap.

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Ah!

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Can you see the suds?

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Yeah.

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'This raw soap is caustic enough to strip paint.

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'We should now leave it for a day to become solid and safe to handle.

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'But we're in a hurry to see if it works.'

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We're going to have a go at some of these everyday muck stains

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that we all know about - chocolate spread, lipstick and shoe polish.

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So, here we go.

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I'll use the home-made soap. Mark will just use water.

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The gloves are just in case there's left-over alkali

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which could burn our skin.

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If we've managed to make proper soap, it should be able to break down stains,

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disperse them in water and leave the glove clean.

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Well, the lipstick is coming off far more easily

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than yours appears to be doing.

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I'm just spreading the lipstick all over me.

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Yeah. Mine's...

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Oh, wow! You've done very well there.

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Let's compare.

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Victory is mine.

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Look, that is, that has come off pretty much completely

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and that is a disaster area.

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Our ancient soap recipe works a treat.

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Made simply from fat and alkali, the chemical reaction between the two

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produces a new substance that will clean away dirt.

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And there's little difference between our home-made effort

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and the more refined soaps we pick off the shelves.

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Over ten million UK homes still use bars of soap

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and most of it starts life as this stuff - soap noodles.

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The basic recipe of fat plus alkali is the same,

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except animal fat is usually swapped for vegetable fats like palm oil.

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Add colour and perfume and you have modern soap.

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Having stripped soap back to its basic components,

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I definitely feel as though I've discovered the original cleaning wonderstuff.

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The recipe might be thousands of years old, but you could argue

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that this magical substance is still the bedrock of modern hygiene.

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'Like a lot of people, I don't buy as many bars of soap as I used to,

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'opting for liquid hand wash and shower gel instead,

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'and I suddenly spot a recurring theme on the labels.'

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Sodium laureth sulphate.

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Sodium laureth sulphate.

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Sodium laureth sulphate.

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Seems like it's not soap itself I've been using but something called,

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you've guessed it, sodium laureth sulphate.

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Check this out - it's also in these shampoos, both basic and posh,

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so it looks like I've been putting it on my hair all these years too.

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But what on earth is this stuff? And where does it come from?

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Is it doing something that good old soap can't?

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Time to look inside one of the most crucial bottles of all

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when it comes to our daily ablutions - shampoo.

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'To find out, I've been invited onto the shop floor of a factory

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'that makes shampoo for supermarket own brands.

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'That must be why McBrides in Bradford seems to virtually run on sodium laureth sulphate,

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'or SELS, as it's often called.'

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Sodium laureth sulphate is the primary detergent we produce here.

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It goes across shower gels, shampoos, baths.

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They all use sodium laureth sulphate, really.

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In terms of a week, we use about 100 tons.

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-100 tons?

-Yes.

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Michael Anderton, a product developer here,

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reckons I need the low-down of what goes into a typical shampoo

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if I'm going to understand the significance this single chemical plays in the formulation.

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So, here we've got the batches that Chris is halfway through making.

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There's a preservative to stop the shampoo going mouldy in the bottle.

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Fragrance and colouring for impressionable folks like me.

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There's a water softener and something to adjust the pH

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to a skin-friendly neutral state.

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But it turns out that up to 50% of shampoo is...

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yes, you've guessed it, sodium laureth sulphate.

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This is a ten-ton vessel.

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It'll produce between 10,000 and 20,000 bottles of shampoo.

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-20,000 bottles - that would sort me out for a lifetime!

-Absolutely.

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'So there it is - I've clearly been relying on sodium laureth sulphate

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'and its close chemical cousin sodium lauryl sulphate

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'to keep my hair clean.

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'But how does it actually work?

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'To answer that,

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'I'm going to need a scientist.

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'So, next stop Warwick University, where chemist Julie Ann Lock

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'wants to show me why this cleaning agent is so good.

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'She's making some sodium lauryl sulphate from scratch.

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'But instead of adding alkali like Mark and I did when we made soap, she's mixing fat with acid -

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'sulphuric acid, to be exact.

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'Amazingly, though, the result is mild enough to use on our skin.'

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If you leave this overnight to cool down,

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you do get something that looks exactly like this.

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This is our sodium lauryl sulphate.

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It feels exactly like a liquid hand wash or a shampoo

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or a conditioner.

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It has that feel of something runny and clean.

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'By changing soap's chemical recipe, you get a totally new kind of detergent.

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'And here's the killer reveal -

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'this synthetic detergent beats my home-made soap hands down in one crucial way.'

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Oh, yes,

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I can see there's a very distinct line of scum there.

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With hard water,

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which is present in lots of parts of the United Kingdom,

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you have calcium and magnesium ions.

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When they react with the molecules that are in your soap,

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they form little scums that don't dissolve in the water.

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'So when traditional soap mixes with hard water,

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'it creates a nasty scum that will lie on the skin or mark skins, baths and clothing.

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'But sodium lauryl sulphate, on the other hand...'

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You're not getting that scummy layer that we found before.

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It's much clearer.

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With lots of lovely bubbles. Just right for my shampoo.

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Because of their resistance to scumming,

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the SLES family of substances

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is much more versatile as a cleaner

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than our humble bar of soap.

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And they've got one more trick up their sleeve...

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just add salt solution and this stuff magically thickens up

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into a handy gel used in toothpaste, shaving foam and laundry liquids.

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Brilliant.

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Now, if the adverts are to be believed,

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then shampoo is only half of the hair care story.

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For that extra radiance and silky shine,

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we should all be taking another little bottle into the shower with us - conditioner.

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But is there actually any proof that conditioner works?

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'Back to the experts for some answers.

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'The gloriously titled analytical hairdresser Beverley

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'is going to put conditioner to the test for us.

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'Hair model Sharon has her locks washed all over with a basic shampoo,

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'like the one we saw mixed earlier. Then only one side is treated

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'with a precision, four-millilitre dose of an average conditioner.'

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Essentially, with a shampoo

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you're looking to cleanse the hair, take the dirt away from the hair.

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With a conditioner, you're trying to put something back on.

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'The objective is to treat the hair with something

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'that'll make it look and feel nicer, and make it easier and less painful to drag a comb through.

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'First up, how's the hair with no conditioner?'

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Here we go, Sharon. I'll have a quick go at combing your hair.

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Don't scream out like my six-year-old!

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Already, I'm hitting quite a bit of knotting here.

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Yeah, that's what I recognise,

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that big lump of tangle.

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'Michael explains the tangle has a rather shocking cause - electricity.'

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When you wash the hair, you leave a negative charge on there.

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You get a repulsion between each hair strand.

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Obviously, the more negative charge you've got there, the more repulsion you'll get.

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'Hair, or rather the keratin it's made of, naturally gains

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'the static electric charge which makes the hair fizzy

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'and reluctant to lie flat.

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'That makes it prone to tangles.'

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'So, what about the conditioned side?

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'Has that dealt with the electric frizz?'

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Straightaway I can notice a big difference.

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It's much, much smoother and silkier,

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all the words that I associate with good conditioner.

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Yes.

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'So it looks like the conditioner's having some kind of electrical effect on the hair,

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'making it much less tangled.'

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So this has been positively charged, in a way?

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Neutralised is what you'd say, because the positive charge is counteracting the negative charge.

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And the positive charge is coming from?

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-Something called the quaternary ammonium compound.

-You what?

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-Commonly known as quats.

-Oh, that's better. I can understand that.

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'So that's how conditioner works.

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'These anti-static quats are our wonderstuff

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'doing something pretty amazing -

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'giving out a positive electrical charge,

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'which counteracts the natural negative charge on hair.

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'Here at McBride they've even got a crazy combing contraption

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'that can tell them exactly how much difference the quats are making.

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'This Frankenstein-esque gizmo combs

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'samples of real hair - happily given by hair donors, I'm assured -

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'from root to tip and measures the force needed to do it.'

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This is the force of the comb moving through the hair here.

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Then along the bottom is the length of the tress.

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'The black line is for a tress of hair washed with the simple shampoo.

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'The red line is for a more expensive shampoo with a few extra proteins and vitamins thrown in.

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'Both are without quats.'

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Actually, there's very little resistance as it moves through.

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But towards the end of the tress, that's where the tangling starts to appear,

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so you get split ends. That's where you're getting to here.

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'So the hair washed with the more expensive shampoo

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'wasn't dramatically easier to comb compared with the basic shampoo.

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'But what happens when you treat the hair with quats,

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'shown by a green line?'

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-Wow, that's a marked difference, isn't it?

-Absolutely.

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The much big bigger effect you get is from the conditioner.

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There's an 85% reduction in the force required to comb through the hair.

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-Visually, as peaks go it's like a molehill up against Mount Everest.

-Absolutely, yes.

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'Clearly the quats are having a noticeable detangling effect.

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'They work on the individual hairs, allowing them to lie flatter,

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'making the whole head of hair look smoother.

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'Quats are clearly pretty clever stuff.

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'If I'm starting to sound a bit like an advert,

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'it's for once it seems I'm not being fobbed off by marketing claims.

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'There really is a science bit involved in conditioners.'

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So from now on,

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rather than fork out 20 quid on a fancy celebrity-endorsed shampoo,

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I might just opt for a more basic one

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then buy a separate conditioner,

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as long as it has a healthy dose of quats in it.

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'By the way, you probably won't see the word quats on labels

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'as it's a generic that encompasses many different chemicals.

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'But you might see cationic surfactant.

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'So that's my hair taken care of.

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'What about my precious teeth?

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'Time to look inside the tube that keeps my pearly whites white.'

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Hm. Not bad.

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When I'm buying a toothpaste, I tend to go for one that promises to make my teeth whiter.

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But now I want to decode the label.

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What's in there that's making it work?

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And is there a magic ingredient

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without which all of our smiles would be various shades of tea-stain brown?

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'According to my materials expert, Mark,

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'the best way to find out if a formula for toothpaste is user-friendly,

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'is to make some and test it on yourself.'

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'It looks like he's got another of his home brew experiments lined up,

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'but I've no idea why he's summoned me to the beach. Still, at least it's sunny.'

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Little bit of fresh air. Fresh, cold sea.

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Hi, Mark, how are you?

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Hi, Jane, how you doing?

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Nice to see you again. I see the shock of working with me last time has made your beard drop off.

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I'm on holiday on the beach. It's too hot for a beard.

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Why are we on the beach, then?

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It turns out the beach is the perfect place to talk about toothpaste and making toothpaste.

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The beach is the perfect place for ice cream and sun-bathing! Toothpaste, I'm not too sure.

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'Mark reckons teeth are unlike any other material

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'found in our bodies and need a special kind of cleaning stuff.'

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The enamel on your teeth is the hardest material in the body.

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It has to be, right? You've got to grind things up and it's got to last you a lifetime.

0:18:560:19:00

Obviously, we use toothpastes to look after the enamel on our teeth.

0:19:000:19:05

But other than knowing it's some kind of paste - err, it's in the title -

0:19:050:19:09

and it's minty most of the time, I don't really know what else is in there.

0:19:090:19:14

Let's have a look.

0:19:140:19:15

To demonstrate what's so special about toothpaste, we're going to make some from scratch.

0:19:150:19:20

You don't see this on Ready Steady Cook. We're going to make toothpaste.

0:19:200:19:24

'First up, water.'

0:19:240:19:26

Aqua.

0:19:260:19:28

'Then stuff to make it taste nice...'

0:19:280:19:30

Sodium saccharine. That's the sweetener.

0:19:300:19:33

Peppermint flavour.

0:19:330:19:34

'..and stop it going off.'

0:19:340:19:36

Sodium benzoate. That's a preservative.

0:19:360:19:38

'A cleaning and foaming agent we're already familiar with...'

0:19:380:19:41

Sodium lauryl sulphate is now going in.

0:19:410:19:45

I'm making a mixture here for something I put in my mouth,

0:19:450:19:48

yet I've just tipped in

0:19:480:19:50

a sort of sister of what goes into shampoo.

0:19:500:19:54

This is weird!

0:19:540:19:55

'..and a tooth strengthener.'

0:19:550:19:57

-This is sodium fluoride. It hardens the enamel up.

-Wow.

0:19:570:20:01

-That's clever stuff, isn't it?

-Yes.

0:20:010:20:03

'There's a lot more in there than I thought,

0:20:030:20:05

'but I'm not sure I've got to my toothpaste wonderstuff yet.

0:20:050:20:09

'And I still don't know why we're on a beach.'

0:20:090:20:12

-Ah, yes!

-Carrageenan.

0:20:120:20:14

-What's carrageenan?

-So that comes from this. This is this seaweed.

0:20:140:20:18

You basically make it into this powder, which is a gelling agent.

0:20:180:20:23

I was expecting this to be a bit thicker at this stage.

0:20:230:20:25

Come on, get it in there.

0:20:250:20:27

I forget men can't multi-task. "Pouring and stirring - what are you asking me to do?"

0:20:270:20:32

'Hm. But if there's a wonderstuff in toothpaste,

0:20:320:20:35

'it has to be the one thing

0:20:350:20:37

'that's particular to the job of cleaning teeth and here it is,

0:20:370:20:40

'something called hydrated silica.'

0:20:400:20:43

The key ingredient is an abrasive. That's what all toothpastes share throughout the history of time.

0:20:430:20:48

-This is silica.

-Silica.

0:20:480:20:50

Yeah, hydrated silica. It's made from the sand we're standing on.

0:20:500:20:53

-Really?

-Yeah.

0:20:530:20:55

'I'm not sure I like the sound of sanding my teeth down,

0:20:550:20:59

'but this doesn't look like coarse grade.'

0:20:590:21:02

You'll get a real feeling for it in your mouth. That's in toothpaste.

0:21:020:21:06

It's very chalky.

0:21:060:21:08

It's that chalky texture... It's a fine grit.

0:21:080:21:12

You've got to get something that's hard but not too hard.

0:21:120:21:15

-Right.

-It's that gentle but hard thing.

0:21:150:21:17

'Let's bung it in and see how it works with the rest of the ingredients.'

0:21:170:21:21

So this is going to really thicken it up.

0:21:210:21:23

-Come on, give it some welly.

-I'm feeling it now.

0:21:230:21:26

-It is turning into something.

-Thank God for that!

0:21:260:21:30

'As well as being an abrasive, the hydrated silica,

0:21:300:21:33

'or posh sand, has given our home-made toothpaste its recognisable consistency.'

0:21:330:21:37

I think that's about it, isn't it? Ta-da! We have made toothpaste.

0:21:370:21:42

Can I taste it?

0:21:420:21:43

Can I stop you for a minute because I think it'll be more exciting if we make stripy toothpaste.

0:21:430:21:48

-We can make that here?

-Well, we can try.

0:21:480:21:52

'Apparently all we have to do is add some food colouring

0:21:520:21:56

'to half the mixture, and if we keep the consistency the same,

0:21:560:21:59

'by a miracle of physics,

0:21:590:22:01

'it should come out of the tube in two stripes that don't mix together.'

0:22:010:22:05

Oh, no, malfunction, malfunction.

0:22:050:22:07

Houston, we have a problem.

0:22:070:22:10

-Come on, drum roll.

-Right, drum roll.

0:22:100:22:12

HE DRUMS ON TABLE

0:22:120:22:14

Oh, look at that!

0:22:140:22:15

It is, it is, it is!

0:22:150:22:18

Genius!

0:22:180:22:19

'So, what's our home-made toothpaste like to use?'

0:22:200:22:24

HE MUMBLES

0:22:270:22:28

'OK, it tastes like a mouthful of chalk dust, but Mark wants me to appreciate how far we've come

0:22:300:22:35

'in toothpaste technology.'

0:22:350:22:37

Try this. This is Victorian toothpaste.

0:22:370:22:40

-It looks like...sludge.

-These are Victorian toothbrushes.

0:22:400:22:44

-Oh, gosh, cinnamon.

-Is that your favourite? No.

0:22:440:22:47

I like cinnamon but not...

0:22:470:22:51

I like it in a latte or a bun.

0:22:510:22:53

I just want to make it clear - that isn't left over from the Victorians.

0:22:530:22:57

We made that to a recipe.

0:22:570:22:58

This is what the Victorians brushed their teeth with?

0:22:580:23:01

Yeah, and the Victorians used this thing called diatomaceous earth.

0:23:010:23:05

That's really the fossilised remains

0:23:050:23:08

of little algae that lived millions of years ago

0:23:080:23:11

and it falls down to the bottom of the ocean and makes this sediment.

0:23:110:23:14

We've been digging it out of the ground ever since.

0:23:140:23:17

'The Victorians spotted that this diatomaceous earth,

0:23:170:23:20

'which also contains silica, by the way, was a useful abrasive.'

0:23:200:23:23

It actually just looks like clay.

0:23:230:23:26

Doesn't have much of a foaming action.

0:23:300:23:34

Has no foaming action.

0:23:340:23:35

'That's because the Victorians didn't have sodium lauryl sulphate.'

0:23:350:23:39

It has gravel action, is what it has!

0:23:390:23:42

'So, even though our modern toothpaste containing hydrated silica is easier on the tongue,

0:23:430:23:48

'how does its effectiveness compare with the Victorian formulation?

0:23:480:23:53

'I want to pit the two toothpastes against each other

0:23:530:23:56

'to see if there's any difference in how they work.

0:23:560:23:59

'And to do that, I'm going to need some special dental devices

0:24:000:24:03

'just like they have at the Bristol Dental School.

0:24:030:24:07

'Dr Emma MacDonald is going to measure the effectiveness of the diatomaceous earth

0:24:070:24:11

'in the Victorian formulation

0:24:110:24:13

'against the hydrated silica in our homemade modern toothpaste.

0:24:130:24:18

'But first we need some teeth to test them on.'

0:24:180:24:22

Oh, Emma...

0:24:220:24:24

Yes, cow's teeth!

0:24:240:24:25

-Look at the size of this.

-Yes.

0:24:250:24:28

Look at that.

0:24:280:24:29

The beauty of using cow's teeth is that we can have a plentiful supply of them.

0:24:290:24:34

Obviously, it's not the same as human enamel but it's very close.

0:24:340:24:38

Is this the common size or have you found the Ken Dodd of the cow world here?

0:24:380:24:43

No, they are actually that size.

0:24:430:24:46

'A cow's pearly white is first cut to size using this delightful tooth saw.

0:24:480:24:53

'Ouch!

0:24:530:24:55

'Slices are then mounted in this rather unique contraption.'

0:24:550:24:59

What's the little red bit there?

0:24:590:25:01

That's actually covering an area of the enamel.

0:25:010:25:05

-So it doesn't get brushed?

-That bit doesn't get brushed.

0:25:050:25:08

It's just the centre little piece that gets brushed.

0:25:080:25:11

'The two different samples of paste are used to brush the teeth 5,000 times

0:25:130:25:18

'before they're put into another fancy device, which gives us the results.'

0:25:180:25:22

'First up, Emma's colleague, Sian, can reveal

0:25:250:25:28

'how much the Victorian toothpaste ground down the tooth.'

0:25:280:25:31

To me, that looks really dramatic.

0:25:320:25:35

This is quite heavily magnified on this system.

0:25:350:25:38

The amount of loss we got from this one was 0.6 of a micron,

0:25:380:25:42

which is less than 1,000th of a millimetre.

0:25:420:25:45

'Ah. So even though it felt like grit in my mouth,

0:25:470:25:51

'I'm assured the Victorian formulation is effective

0:25:510:25:53

'in toothpaste science terms.

0:25:530:25:56

'Now, you might think that the much smoother, modern formulation

0:25:570:26:00

'with hydrated silica would have less effect,

0:26:000:26:04

'but, amazingly, the results are very similar.'

0:26:040:26:09

What we're seeing is 0.81 of a micron.

0:26:090:26:12

'So, modern hydrated silica gives you abrasive power,

0:26:120:26:17

'but without the gritty texture.'

0:26:170:26:19

'What's more, the size of the hydrated silica crystals can be manipulated

0:26:190:26:23

'to make different kinds of toothpaste.'

0:26:230:26:26

You can think of the particles within them a bit like clouds, really.

0:26:260:26:30

For example, in a whitening toothpaste,

0:26:300:26:33

you'll have the particles that will be quite dense, like a dense cloud.

0:26:330:26:38

Then you could have light, fluffy clouds

0:26:380:26:40

with less tightly-packed particles,

0:26:400:26:42

which you might find in a children's toothpaste.

0:26:420:26:45

'And hydrated silica earns its spurs as a wonderstuff in other ways too.

0:26:460:26:51

'It's odourless, tasteless and chemically inert,

0:26:510:26:55

'and turns up in the production of cosmetics,

0:26:550:26:57

'paints and even beer. Clever stuff!'

0:26:570:27:01

'When I first started this journey

0:27:030:27:05

'delving into the science hiding in our bathroom cabinets,

0:27:050:27:08

'I had no idea where it was going to take me.

0:27:080:27:11

'But discovering the wonderstuffs at the heart of things

0:27:110:27:14

'as mundane as shampoo and toothpaste has genuinely surprised me.'

0:27:140:27:18

-Made from the sand we're standing on.

-Really?

0:27:180:27:21

I love the fact that the basic soap recipe hasn't really changed

0:27:210:27:25

since they were using it to spruce themselves up for a night out in ancient Babylon

0:27:250:27:30

about 2,000 years ago.

0:27:300:27:32

But for me, the stand-out fact has to be

0:27:320:27:35

that there's this amazing little chemical

0:27:350:27:38

that can actually change the electrical charge on my hair

0:27:380:27:42

and make it more manageable.

0:27:420:27:44

That's brilliant!

0:27:440:27:46

'Next time, I get back to nature,

0:27:470:27:50

'on the hunt for some of the wonderstuffs that secretly keep our homes clean.

0:27:500:27:54

'I get far too intimate with a serial dirt killer...'

0:27:540:27:58

Oh, my God!

0:27:580:28:00

'..that can disappear without a trace.'

0:28:000:28:02

Oh, that's revived me.

0:28:020:28:04

'I track down the natural source of a wonderstuff that's revolutionised wash day.'

0:28:040:28:09

They knew what hard work was in those days.

0:28:090:28:11

'And Mark whisks up a recipe for a home-made grease buster.'

0:28:110:28:15

I knew when you called me here you were taking the piss.

0:28:150:28:18

Subtitles by Red Bee Media Ltd

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