- 8 minutes ago
Category
📺
TVTranscript
00:00G'day, I'm Dr Karl.
00:05Now, over my long and varied career,
00:07I seem to have picked up quite a bit of knowledge.
00:11I certainly get asked a lot of questions,
00:14but don't let that fool you.
00:16I do not have all the answers.
00:18There are plenty of things that I have yet to investigate.
00:22These torrents, these rivers,
00:24these floods of conveyor belts and chips.
00:27Like how everyday items are made.
00:30Ah! I missed!
00:32I'm getting too far!
00:34And that's the idea of this series.
00:36What an absolutely amazing arm.
00:38Aren't they incredible?
00:42Ah! It did it!
00:43Oh, look, there it is!
00:44Yes.
00:45A perfect oval.
00:46I want to find out how things work.
00:50This time, we investigate a wondrous food item
00:55made in partnership with microscopic life forms,
00:58it's a marvel of food engineering
01:02that's been with us arguably since the dawn of civilization.
01:08Fresh, hot and straight out of the oven,
01:10it's irresistible any way you slice it.
01:15I want to know, how do they make bread?
01:20I'm at the Goodman Fielder factory on the Gold Coast in Queensland.
01:27Here they produce a staggering quantity
01:31of over 20 different types of bread.
01:34And I'm looking for the man who knows all about baking.
01:38Hi, g'day, I'm Carl.
01:39Hi, Carl, I'm Peter.
01:40Now, I believe you're one of the top bakers here.
01:42Yeah, I'm the quality manager.
01:43I'm part of the team here at the site, yeah.
01:45I've been baking for 42 years, Carl.
01:48Jeez, man, you must know so much stuff.
01:51We produce up to 100,000 loaves a day.
01:54What?
01:55100,000 loaves a day.
01:56Divide that by 25, that's 4,000 loaves an hour.
02:00Yep, yep, 4,000 loaves an hour.
02:02That's one every second.
02:03Yep, absolutely.
02:04Wow!
02:05You will start baking at 12 today,
02:076 o'clock it'll be on a truck for tomorrow's market.
02:10Today, Peter is showing me the secrets behind their most popular loaf.
02:16Sandwich bread.
02:17OK, the bread part we understand, but sandwich?
02:22People have been putting food between slices of bread
02:25for at least 2,000 years.
02:27But it didn't get the name Sandwich until 1762.
02:31In the town of Sandwich in England,
02:34there was a man, John Montague,
02:35who was also the Earl of Sandwich.
02:38Now, he loved his card game so much
02:41that in order to keep on playing
02:43and eat at the same time without getting his cards greasy,
02:47he had his valet bring him a slice of roast beef
02:50between two slices of toasted bread.
02:53People noticed, copied, the word spread,
02:56and that's how we have the word Sandwich.
02:59OK, that's enough history for now.
03:01We're on the clock and there is baking to be done.
03:04This is going to be, I'm guessing, a white bread?
03:06A white bread, yep.
03:07OK, and I guess there's a recipe?
03:09Yep, we've got a recipe.
03:10We're going to get you to weigh up some of this.
03:12Oh, it's a recipe? Yes.
03:13OK, where do I start?
03:14You take the scoop, so there's salt over here.
03:16Salt? How much salt do I put in?
03:18If you look at the salt, you want 1.95 kilos.
03:20So 1.95.
03:22Yep, that's a pretty big scoop.
03:24And this, nearly two kilos, is going to be part of all the final weight of the mixed feed.
03:30300 kilos.
03:31Tip it all in.
03:321.9.
03:33Next, three scoops of what's called bread improvers,
03:38followed by what gives bread its soft, chewy texture, gluten.
03:43So that's all your dry ingredients?
03:45Yeah.
03:46They go into the wheelie bin, then to the back of the mixer.
03:49Man, those are huge for sure.
03:51Yeah.
03:52Now, storing ingredients in a wheelie bin might look unusual.
03:56Oh.
03:57But it's a large container and on wheels.
04:01So now we're loading the dry ingredients into the mix.
04:06The last dry ingredient requires its own delivery system.
04:10So those pipes going in from the ceiling, that's your flour line going in from the mixer?
04:14Flour?
04:15To the flour?
04:16There's a pipe like the guy under my head or something.
04:18Yeah, there's a 50 tonne silo out the back.
04:20It goes to a hopper and it dumps the flour into the hopper up top.
04:25Next, the wet stuff.
04:27The water and yeast are pumped in with a touch of canola oil and vinegar.
04:32And now the mixing can begin.
04:35You can hear it vibrating now.
04:37Yeah, I've got my hand here on the spill vibration coming through the system,
04:41even though it's bolted to the floor.
04:43Now, this will mix for about three minutes.
04:45OK, and how many batches go through in a day?
04:47I'll do 200 batches a day.
04:48So what does 300 kilos of mixed dough look like?
04:53Oh!
04:54Look at that!
04:57It was still spinning around while it was being thrown out.
04:59Yeah, correct.
05:02It's, um...
05:03It's a bit sticky.
05:04Why is it so sticky?
05:05From the water and the oil and mixing it all together.
05:08And the extra gluten?
05:09Does gluten make it sticky?
05:10The gluten will hold it together.
05:11So what we do with this now is we actually...
05:13Oh, look at that!
05:14So this is how you tell where you've mixed it long enough.
05:17That's what they call the gluten strand.
05:18Like going...
05:19Yeah, holding it together.
05:20What, what, the crisscross?
05:21Yeah, that gives you your structure of your bread.
05:23You can actually see the gluten with the naked eye.
05:26Correct.
05:27I had no idea.
05:29But how does this lump of floppy, sticky dough become a loaf?
05:34So what happens to this guy here?
05:36It'll go up into the divider.
05:41The divider, appropriately, of course, divides the dough.
05:45It rolls it into balls and then pumps them out.
05:49Oh, look at them go.
05:51At a mesmerising pace.
05:53So now you've got a dough ball.
05:55Theoretically, that would become...
05:57That'll become a loaf of bread.
05:59How much do they weigh?
06:00800 grand.
06:01Oh, look at this.
06:02There's a weighing scale.
06:03Got a check wire here that measures every dough piece.
06:06It takes less than a second to weigh each dough ball.
06:10And if they don't measure up...
06:12Whoa!
06:13Whoa!
06:14But two of them fail.
06:18If it's below the weight we're looking for, it just rejects them.
06:21And so is that just a blast of compressed air that pushes them off?
06:25That pressed air just pushes them off, yeah.
06:27Just air.
06:28I never thought that rejection would be so entertaining.
06:32Wow!
06:33Man, that comes at you so fast.
06:35I feel as though I'm going into a higher state of consciousness.
06:43Being hypnotised by the little balls of dough.
06:45All almost perfect.
06:46It simply pays for all real.
06:48Ah!
06:49Like that one.
06:50That one!
06:51And that one!
06:52That one!
06:53Come on!
06:54Stop!
06:55Stop!
06:56The ones that failed rejoin the divider for a second chance of making weight.
07:01So these are the good ones, so what happens to them now?
07:04So these go around to the right weight, so now they go around here.
07:07Oh my God, what's this?
07:09This is what they call the intermediate prover.
07:12What are they doing here, Peter?
07:13They're having a rest.
07:14They're having a rest?
07:15They're having a rest.
07:16Why?
07:17To let the yeast start to work.
07:18Yeah.
07:19And the dough start to grow.
07:21Make the dough nice and soft.
07:23And this power nap takes only three minutes.
07:28Thanks to a high level of yeast in the dough.
07:31How much yeast would there be?
07:33There would be 8%.
07:348%?
07:3510% of that would be yeast.
07:37So 1% would be 8 grams, so 64 grams of yeast.
07:42Yep.
07:43Wow!
07:44This dough is like a living creature.
07:46It is a living thing.
07:48Bread making, like many living things, has been evolving for generations.
07:55If you want to be poetic about it, you can think of bread as being a cornerstone of our
07:59civilisation.
08:00Way back, after we had learned to control fire, somebody came across some wheat and they got
08:06the grains and they ground them and did things and then baked them and blow me down.
08:11Flat bread.
08:12And then, by accident, some wild yeast landed on the dough mix and fermentation happened
08:20and gases came off and suddenly you had a bread that rose.
08:24And that yeast powered rise can be seen and measured with a very simple test.
08:30Fermentation experiment 101.
08:33Yeast plus sugar plus water should give us some gas.
08:38Exhibit A.
08:39Yeast.
08:40Now that is a living creature.
08:41If it wants to survive, seeing how it's not a plant, it needs some food.
08:45For this demo, instead of flour, I'll use sugar.
08:49When yeast eats sugar, it gives us carbon dioxide and a bit of alcohol which evaporates
08:55off anyway.
08:56Now, how are we going to tell this?
08:59We add the balloon, seeing if the balloon expands due to the gases, carbon dioxide, being
09:07produced.
09:08And, with a bit of patience...
09:14Isn't it amazing what one short hour will do?
09:17All this bubble of carbon dioxide, oh my heavens, and that is why and how the dough will rise
09:24when you add yeast to the mixture to give you this beautiful fluffy bread.
09:28But the yeast will need a crucial helping hand from another ingredient.
09:33One that can help give this bread a perfect texture.
09:37Now, as you've guessed by now, I love stainless steel to pieces.
09:41And this huge tank has 15 tonnes of canola oil.
09:46It has two main purposes in baking.
09:49When you're baking the bread, the little tiny bubbles of carbon dioxide, they slide past each
09:56other because there's canola in between.
09:59And so you get a multitude of tiny bubbles instead of just one giant bump.
10:03And secondly, the canola oil gives a soft, delicious announcement of the bread.
10:11Producing this key ingredient for sandwich bread takes a surprising amount of effort.
10:23Luckily, Harold, the director of Cootamundra Oil Seeds in the Riverina region, is an expert
10:29in turning the seeds from the canola plant into cooking oil.
10:33So after it flowers, the seed pod is generated.
10:39And this is what contains the oil.
10:4140 to 45 percent oil in this seed.
10:45So the seed is going to be cold pressed in our plant.
10:48The plant is essentially an extraction process and a refining process.
10:54And step one is isolating the seeds.
10:58All right, so here we have our seed cleaning process.
11:03The seed, it's vibrated.
11:05It's a giant motorised sieve.
11:08Shake, shake, shake.
11:10And most of the other plant material is removed.
11:15So the cleaned seed, it travels across and up into the seed conditioner.
11:22Any more admixture that's still in there comes to the top just due to the difference in density.
11:29Now the black canola seeds are ready to be crushed in a machine ominously named the Expeller,
11:38which turns and twists using pressure and friction to squeeze out the oil.
11:43Now as the oil is expelled, you can see there are still some solids that come with the oil.
11:51The oil then passes through a sieve for further refining.
11:56And the meal is captured here and stored.
12:00The meal is then pressed a second time to extract more oil,
12:04with the waste meal going to animal feed.
12:16This oil is called the first press.
12:19But canola oil needs to be clear and neutral in taste and smell.
12:24Now here we have a sample of the oil.
12:27Oil is still quite dark, has quite a bit of odour.
12:31To refine it, weirdly, you first need to dirty it up.
12:37You see, the oil is mixed with powdered natural clay,
12:42which can absorb any impurities and odours.
12:46This vessel here slowly agitates the oil-clay mixture.
12:52Once the clay is removed and the oil is filtered,
12:56you get this golden result.
12:58So on the right here we have the intermediate oil,
13:03which has been cold processed through the expeller.
13:06And to the left is the final refined product
13:10that is more neutral in taste, in colour and in odour.
13:14And this is exactly what the sandwich bread recipe needs.
13:18Back at the factory, our does are out of the intermediate proofer.
13:27They've had their short rest and are slightly puffier than before.
13:32They'll still grow much, much larger,
13:34but first the balls will say goodbye to being balls.
13:39So your dough ball comes through the top,
13:43it goes through a series of four rollers,
13:46that flattens it out into a nice long sausage
13:48and cuts it into four pieces.
13:50It gets chopped here, and then what happens over there?
13:53It just turns the dough pieces around.
13:55Each of the four pieces gets flipped by a degree.
13:57Yep.
13:58All this squishing, rolling, cutting and folding is not random.
14:03That's actually precise sandwich bread engineering,
14:07altering the internal structure of the dough.
14:09Makes the slice of bread stronger,
14:11and when you go to spread your margarine or your butter on there,
14:14stops it from tearing,
14:15because you've got a stronger cell structure.
14:17Peter says I'll be able to test this out later down the line,
14:21but for now this lumpy proto bread has some more rising to do.
14:28Are they actually going to rise all the way to the top?
14:30They're going to rise to the top.
14:31You're kidding.
14:32The yeast is now growing, it's moving.
14:34And inside the proving machine
14:36is a tropical moist paradise for the yeast to multiply.
14:41The temperature set about 40 degrees.
14:43Yeah.
14:44And the humidity is about 80%.
14:46Wow, like the wet seeds in Darwin.
14:48Yeah, absolutely.
14:49And how long is the proving time like?
14:5075 minutes.
14:52Luckily, there's an earlier batch just coming out,
14:55and it's risen all the way to the top of the tin.
14:59Very soft and full of gas, full of air.
15:02Then it goes into the oven,
15:04so when the bread goes in,
15:05the lid comes down on the top of the loaf to make it square.
15:12When the bread goes in the oven,
15:14at 60 degrees it kills the yeast off.
15:16So you mean that my new best friend forever, the yeast,
15:19by the time they get to the end of the line they'll be dead?
15:23Absolutely.
15:24They're dying for us so that we can live.
15:25They'll die in the baking process.
15:27Thank you, Eugene, for your service.
15:29And here's the yeast's gift to humanity.
15:32Do you like that smell?
15:33I love that smell.
15:42Oh, that's warm, isn't it?
15:43The bread temperature is about 96 degrees internally
15:45when it comes out of the oven.
15:47Now that's too hot to handle.
15:49So a machine called a D-panner
15:52uses precise jets of compressed air
15:55aimed at the sides of the tin
15:57and it unsticks the bread from the pan in one go.
16:00And then low-pressure suction caps
16:02gently carry the loaf onto a conveyor belt.
16:05And now we've got a loaf of baked bread.
16:13It's warm.
16:14Warm.
16:15Quite hot.
16:16And I can see the four sections
16:17which I've never noticed before.
16:18And then it goes down these conveyors
16:21into the cooler.
16:22Why do you have to cool it down?
16:24So you can slice it.
16:25Well, we can't slice it now,
16:27but we can do this.
16:29Oh my God, you're perfect in all the seeds.
16:31We broke it in the middle on one of the four-piece lines.
16:33You can see how nice and white and fluffy it is.
16:39Oh, it sort of vanishes in my mouth.
16:42It's too hot.
16:43Right, so it has to cool down.
16:45Yeah.
16:46For your slicing machine.
16:47Still, there's nothing like warm bread.
16:50I remember when I was a kid
16:51my mother sent me down to the corner shop
16:53to buy some bread.
16:54It was so delicious that by the time I...
16:56You ate the middle out of it.
16:57I ate the middle out of it.
16:58Oh, I got in trouble.
17:00I was so bad.
17:02Anyway, to cool this bread,
17:04the facility uses a massive double spiral cooler tower.
17:08It blows cold air to bring the loaves
17:11to a slice-friendly 30 degrees Celsius.
17:17It goes up 10 metres or something.
17:19About 10 metres high.
17:20And what's the total length of all that?
17:22There's two and a half kilometres of belt in there.
17:25How long have you stayed in there for?
17:2675 minutes.
17:29And, yes, 75 minutes later,
17:31the cool loaves are ready for slicing and packaging
17:34under the watchful eye of my new guide, John.
17:37This is a bandsaw slicer.
17:41You might see bandsaws around for cutting metal.
17:44This is a very similar process.
17:46Inside, you can see the fingers.
17:49Those fingers move in and out
17:51so that you can adjust the slice thickness of the product.
17:54How thick can the slicer be?
17:57From about one centimetre to about one inch thickness.
18:02I can just barely see it, but they are sliced.
18:05Is that me?
18:06Yes.
18:07I broke the light barrier.
18:08I was bad.
18:09Sorry.
18:10Yes, there is a light fence around the slicer.
18:13It'll safely stop it from slicing
18:15if any naughty fingers cross the beams.
18:18So, after the bread has gone through the slicer,
18:21it travels into the bagger system.
18:23As you can hear the air burst,
18:25that is inflating a bag and putting it over the loaf.
18:30When the machine misses a loaf,
18:33it takes a human about 12 seconds
18:35to get the bread into a bag,
18:37including putting on a clip
18:39the bag closed and the bread fresh.
18:42But using robots and compressed air,
18:44the whole operation usually takes about a second,
18:47including adding the little clip thingy.
18:50The bread clip was invented in the 1950s
18:53when Mr. Floyd G. Paxton, on a plane flight,
18:57carved one using an old credit card and a pen knife
19:00to reseal his free bag of peanuts.
19:03Today's version is exactly the same,
19:06but made of recycled cardboard.
19:09Now, how do we know if this bread is sandwich grade?
19:14Ah, g'day. Hi, I'm Carl.
19:16Hi. Hi, I'm Amy.
19:18Technical manager Amy at Quality Control has the answers.
19:22Yep, so this is what we do day to day.
19:24So we get the bread off the line, take the slice out.
19:27Ah.
19:28And put in this one.
19:31Right.
19:33And that will give you an image.
19:35Ah.
19:36OK, so I'm pretty sure that's not a multicoloured cushion.
19:39This machine reveals the hidden structural engineering of a slice.
19:43OK, and what are we looking at?
19:45Colour, dimension, shape, cell size and elongation.
19:50Cells are the tiny bubbles that make up the spongy structure of the bread.
19:54And these cells got formed because of the creation of carbon dioxide by the yeast?
19:58Yes.
19:59Right.
20:00And with the sandwich bread we want to understand if our crumb structure is open.
20:05And crumb just means the white parts.
20:08If there are too many big holes, that's a sign of a weaker bread.
20:14Testing the firmness of the bread.
20:16The firmness?
20:17Yes.
20:18And we want to understand how resilient it is.
20:19Resilience is like elasticity.
20:20Yeah, so when you touch it and it bounce back.
20:23Can I do that?
20:24Yes.
20:27We want a bit of Brazilian because when you've got a margarine on it, it just breaks.
20:33We don't want that to happen.
20:34So the bread has to have some structural integrity so it won't tear apart.
20:37Yes.
20:38And you say margarine rather than butter, why is that?
20:42Because I eat margarine.
20:43You don't eat butter?
20:44I do sometimes.
20:45And back at the slicing station, Amy has a practical way to show me what the scanner sees in the lab.
20:54Yeah, just watch this.
20:56OK.
20:57And I'm going to do it this way.
20:58Oh!
20:59Oh!
21:00When we will see at the end.
21:05Oh my God!
21:06Can you count it long ways?
21:07Yeah?
21:08And that change alone turns a strong resilient slice into a fragile soft one.
21:15This one is tighter from structure.
21:17This is what we would look for.
21:19And that one, we've got some holes in more open.
21:22The cells are definitely bigger, aren't they?
21:24Yeah.
21:25When they come this way than this way.
21:26Yeah.
21:27I had no idea that the physicality of making bread was so important.
21:30It is, yes.
21:31But this massive operation got me thinking about bigger things.
21:35I'm very aware that the more loaves we produce, the more we potentially end up wasting.
21:42But there's something brewing in Melbourne, in Victoria.
21:51In the wee hours, away from public eyes, a group of men wipe clean a whole supermarket worth of bread.
22:07Once a month we go to supermarkets around the area and collect bread.
22:14All sanctioned, of course.
22:16So it's on the shelves, goes unsold after a few days and they have to rotate it out.
22:22And at the moment, you know, it's typically going to landfill or stock feed.
22:29And that's about 100,000 tonnes in Australia per year.
22:34That's roughly 314 million loaves each year.
22:39There's so much bread that's in surplus.
22:43But we can use it in our beers.
22:46And here in Clifton Hill at Local Brewing Co.
22:50Another delivery.
22:51Yeah.
22:52Is where founders Paddy and Nick learned how to transform bread into beer.
22:58Ready for another batch?
23:01We can use any bread, but we're just focusing on white bread.
23:05It's the most wasted type of bread.
23:08We grind it up and we process it into a brewing ingredient that we then put into our beers.
23:15To do so, Brewing Wizard Andrew carefully combines selected enzymes with the breadcrumbs.
23:23These enzymes will break the starches down into sugars that the yeast can consume.
23:30Hello yeast, my old friend, we meet again.
23:33Except this time, it's brewer's yeast.
23:37Which is great at turning sugars, in this case this bread extract, into alcohol.
23:44Typically beer is made out of 100% malted barley.
23:52What we're looking at doing is replacing 20% of this with our extract, which is made out of reclaimed bread.
24:01And once the yeast joins the barley and liquid bread, it'll turn the mix into beer.
24:07And that would be around one loaf per case of beer.
24:12Then when it's ready, keg up the taps and we can serve it.
24:17Over the past year, more than 500 kilos of surplus bread were sneakily recycled into beer.
24:24All thanks to some clever science.
24:27We're finding it's actually easier to hide it in like a bigger, hoppier ale, than it is to hide inside a simple, clean lager.
24:34But as we get better at it, we'll be able to use it in many different beers.
24:41And here, at the bread factory, they're also doing their part.
24:46So this is a return truck, which returns bread, which is not sold in a store and past it's used by date.
24:52And you don't want to just chuck it in a bin. So what do you do with it? I'm hoping something good?
24:56Recycle it and to pig feed or cattle feed.
24:59Right. Well, at least getting reused.
25:03One thing is for certain, fresh bread is what everybody wants, but the window between fresh bread and stale bread is a short one.
25:13So John wants to show me how they move a never-ending stream of bread onto market shelves as quickly as possible.
25:20John, this is an Aladdin's cave of wonders.
25:26This gantry can hold roughly 85,000 units of bread.
25:31That's enormous. How does this whole gantry system work?
25:33So every crate that enters this gantry system or leaves it is assigned a unique identification code.
25:41It works out what stores ordered that product.
25:45How many different stores would you send it to?
25:47500-plus stores a day.
25:50The machinery and the team gather each load, and the stacks are ready for the road.
25:56We just push these straight onto the truck.
25:59Push them straight into the truck there, yeah?
26:01Each truck is designed to be able to fit two dollies side by side.
26:07And then what about the space between there and the ceiling?
26:10This floor, once fully loaded, will be lifted right up so that we can fit another row of these ten high underneath.
26:17How clever.
26:20You're going out to people ranging from a little corner store up to the big megaplexes.
26:25Roughly what distance would you trucks deliver in coverage week?
26:28Across Australia, we would travel of the equivalent to the moon each week.
26:34Wow, that's like 380,000 kilometres.
26:37That is such a huge distance.
26:39It shows how important bread is, that we have to cover that distance.
26:44Wow.
26:48On one hand, the story of bread starts with ancient agriculture,
26:53takes us through to the humble yeast, and finishes with a golden loaf.
26:58But bread is more than just a mixture of tradition and science.
27:03Bread is food.
27:05In each slice of bread, you have a mixture of agriculture, biology and community.
27:12It's a simple snapshot of our entire civilisation.
27:16Next time, we step into the making of a timeless trendsetter.
27:20What?
27:21The question is, how do they make...
27:24...boots?
27:29You can stream all of Dr Karl's How Things Work now on ABC iview.
27:34Or up next in Human, discover how our ancestors pioneered new ways to control nature.
27:39Now.
27:43I know that the росys.
27:45The
Comments