On this episode of Food Lab we're
investigating the basic chemistry that
is baking. Now baking is one of those
inexact food sciences but there is some
simple chemistry that will help explain
many of the issues we have when we bake.
Well then the law of conservation of
matter says that matter is neither
created nor destroyed but just changed
from one form into another. So if you
think of baking you have flour, you have
butter, you have eggs, you have sugar,
you're making a cake. Put them all in the
mixture, you're going to end up with
flour, sugar, egg, and butter at the end.
You may have some water evaporating
during the process as a gas but the same
ingredients will be present just in a
slightly different form. In that law of
conservation of matter why do we use
word equations to help explain that?
Equations are good because they show us
what's happening in a straight line,
they're really visually appealing and
they can see what's been put into the
reaction and what's eventuated out of
the reaction, so it's a good way of
looking at it. You mentioned baking
powder and there are other I guess
raising agents. How do raising agents work
to one, make a cake rise, and then hold
it in that position. There's a range of
different raising agents available, so
ultimately they're trying to trap air
into the cake or produce carbon dioxide
gas as a result of chemical reactions. So,
for example, baking powder it's a
combination of sodium bicarbonate and an
acid of some sort and we know that when
you combine a base, which is the
sodium bicarbonate and acid, you get a
reaction that produces carbon dioxide
and water and a salt. So it helps it to
rise that way. So rises, it forms, it
bubbles ... why doesn't it then, and I've
had this happen to some of my cakes, why
doesn't it collapse? Ah, that's a really
interesting question. So, there's a
protein in the flower called gluten, so
gluten in Latin means glue so the gluten
actually helps the cake to stay together
but it also coats the air bubbles and
helps when to stay in place. So what
happens is there's two components to
gluten, so there's glutenin and gliadin.
The gluten is the stretchy one, so it
helps the cake expanmd in a stretchy
way while incorporating air,
and the gliadin gives it viscosity and
texture. Generally you're told when
you're baking if you're making a cake or
pikelets or something like that, not
to overwork the dough. For something like
bread you want to work it quite a bit, but
I've always been told that it activates
gluten, is that true? That's absolutely
right, so the more you work the dough, the
more gluten you're going to have
activated. So, if you would like a fluffy
sponge cake you really shouldn't be
touching that at all, so you should be
folding it very lightly, maybe with a
knife or just very, very lightly, and you
would have whipped some air into the
egg that's in that sponge so they usually
have a lot of egg in them to incorporate
air into the mixture and you don't
want that large gluten development
because it will be quite chewy. So we don't
want a chewy flat sponge, but certainly
with Fred we want the bread to rise,
you'd use a higher protein flour which
refers to the gluten, if you're making a
bread so that you get more air pockets
forming and better rising. Now that we've
had our little chemistry lesson, let's head
to the Sofitel Brisbane Central and see
how they use the law of conservation of
matter and matter and leavening agents to bake one of
their signature cakes. Pastry chefs
aren't renowned for being super clean in
the kitchen. Yeah, that's true, and because also
we work hard. Very good!
The Sofitel Brisbane Central is renowned for
its French baked treats, so it's the perfect
place to learn a little more about the
uses of rising ages in baking. Standing
in the pastry kitchen of the Sofitel in
Brisbane with the executive pastry chef,
Joel - how do I pronounce your last night name?
Hey-let. Hey-let? Okay. Joel Helot. What are we
making chef? So today we're making the
King cake. It's basically like
a fruit cake, with the same sort of ingredients.
What I like straight off is there's not many
ingredients there. There's not many ingredients, yeah.
That makes it taste fantastic. Yeah, which is
... food is about the taste. Yes, that's it.
It has to taste good. That's it. That's the end of the
story. They don't have to be complicated.
So what do we doing for this one?
So for this one we've got one, two,
three, four, five, six, seven, eight
ingredients. So one, two, three, four go
inside here, mix all together. We hide
everything inside and one, two, three, four
, that's for the top of the cake. And all the
equipment we need is here? Yes.
As baking and pastry becomes more
complicated you need more and more
equipment, which makes it, I think, more
expensive for everyone to do at home. Yes.
And more complicated, this is a
whisker, bowl and baking tray. Yeah, and
even so you can use even, you know, your
typical team, to put this mix
inside of it. Exact same mixture? Exactly
right, the same finish, the same result.
So basically you don't have to buy
some expensive mould, you can put in
your own. Exactly right. Alright, let's go.
Okay first. So first, we put
the butter. This is quite soft. Yes, a little bit soft
at room temperature. But you can
use the microwave in 10 seconds.
Sugar. Sugar, the start of
every good cake. Butter and sugar, just mixed together.
Slowly, like that. Eggs.
One by one, because if you
put too many it doesn't mix together.
I've always wondered.
It's getting softer and softer, but it
look very smooth. Yeah. So
one more.
That's enough. I've got my flour and my sugar.. So you've got your flour and
what else is in with your flour? Bi-carb. Bi-carb soda?
Yes. Okay, so that's ... what's
the bi-carb do. The cake will rise.
So that's the leavening agent. That's it, if you
don't have this the cake is going to be
heavy and it's going to be flat.
Yeah, yep. As soon as you make this
ingredient we should, we start to kick and
as soon as you put the recipes in the oven
you see it again.
So you almost get two leavening stages out of it. Yes.
And also, we need to stick with the ratio. Yeah.
You know what I mean? It is five grams,
it's five grams. If you put too much
everything's going to bubble and the mixture
is going to split. So
I've got plain flour.
And so for this part of the mixture are you just want to
bring it together or are you going to
beat it quiet? Because if you mix too
much the mix beginning to take even more,
so we want something light but
not too light because we got the baking
powder, is getting too thick anyway.
So that's how you know if you do it by hand,
you're not getting to be crazy, you
know ... like the machine. With the motor.
Yep just until it comes together. Exactly right.
And this is a good base cake mixture
for anything really, isn't it. Yes.
you can add any flavour that you want to
that. And even so you can use that as
a sponge base. It's a little bit
more heavy but it's much easier. Yep. So,
up to this point it's really versatile,
add whatever flavours you want. Exactly right.
So what I'm going to do, I'm going to
use a piping bag, or if you don't have a
piping bag you can use a spoon.
I think piping bags are fantastic to have in
the kitchen at home because it
helps you control everything, keeps you
clean. Yeah. Pastry chefs aren't renowned for
being super clean in the kitchen, they're a little
bit messy. Yes, that's true but because also
we work hard. Hahaha. Very good.I'm
going to spray this, a little bit.. So
I'm going to pipe the mix half way just
like this.
Look at how smooth and silky that cake
mix is with no machine. That's it. And at room
temperature for that. That's it.
I think the real key. Yeah, so hopefully.
And the same if you were using a big cake tin.
Just go halfway. Yes, halfway. So, I've
got some almond flakes here, simple things.
You don't have to be precise. You don't have
to push them in, the cake will rise around it?
Exactly right, so it will look good visual-wise.
So then I'm guessing they go in the
over, chef? Yes, For half an hour and for
180 degrees.
And we're in the hotel where these go. Each guest who comes into Sofitel has a little gift and
that's what we do for them for this
month. So when I arrive in my room I
should find one of these?
You should find that. We have plenty left, so have as many as you want.
I'll shout out for you, send up some more cake.
From the simplest of French cakes to a cake that all
bakers would have had issues with
over time. Up next I will show you how to
make a perfect sponge, and just to make it
a little more interesting we'll be
cooking outdoors in a pot on an
induction plate. You're going to think it's magic
but it's not. The magic of
television but this is done live.
Chemistry is one of those fields of
science that's really prevalent whenever
you're in the kitchen but none more so
than when you're baking i'm going to
show you the role that chemistry plays
in baking and show you how to cheat your
way around a good sponge. Now, you
wouldn't think you can make a sponge outside
but I'm going to show you how you can do
it in a pot and we're also going to make
a pizza in a fry pan. So you don't need
to take an oven with you and you still
get some baked goods when you're
outdoors. So the easiest way to basically
make a sponge if you're going to make it
at home is cheat a little bit and use
cornflour. My grandmother would kill me
for doing this but when you're cooking
outside and we're cooking in a saucepan
on an induction it's the best way to go.
There's still a lot of chemistry
involved in this time, so the first thing I
have to do is slip my eggs. Eggs are
really, really, really important in
cooking and probably more so again in
baking. Eggs made up of two very, very
different things - the yolk and the white,
so I want to split them apart. I want
whites in one bowl, yolks in the other,
because they react very, very differently.
So ... whites in this bowl, yokes in my other
bowl and then I'm going to whisk the
whites to try and get ... a sponge is meant
to be light and fluffy so the idea is
get as much air or as much air bubbles
as you as you can into the sponge and the
best way to do that is every chance you
get incorporate air. So you can see how
that's changed, we've got what looks like
a lot more egg white in there, what's
happened is our eggs, the protein in the eggs
has denatured and then bonded with other
proteins and started to form this
lattice structure which grows the
egg white in size and it traps air
bubbles in that structure. So now we've
got it to a soft peak, I'm going to rein
in my caster sugar and keep on going
through a stiff peak, and this could take five
minutes. I want it to be nice and glossy.
That is my egg white done and as I've been
going I've been checking to make sure
that the sugar is dissolved, once the ... you
can pinch it between your fingers, you
know, feel any granules of sugar, it's
basically done. So yolks, I don't mind that there's
still a little bit of egg white in there,
that's fine. Some vanilla in there. About
a teaspoon of vanilla. And then
again, I'm just trying to incorporate as
much air as I can into every component.
And that's my eggs, then you see
obviously they're not going to react the
same way the wires we've got some
bubbles in there which is really all I
was after. So we've got cornflour here, one
and a third cups of cornflour, and about
two tablespoons of regular flour. I want
to bring all my dry ingredients together,
so again I'm sifting to get as much air
in as I possibly can, so my plain flour
goes in and then as a raising agent i'm
going to use baking powder. You heard
Olivia talk about you've got a base and
an acid, when bases and acids come
together they react and they give off
carbon dioxide. They need some sort of
water or moisture to do that we've
popped two teaspoons of our baking
powder in and when we add our moist
ingredients which is our egg yolks and
our egg whites to that it will start to
react and it will give off those little
bubbles of carbon dioxide and they will
get trapped in the structure of the cake
and again we're working on getting a
nice light fluffy cake. So now we have to
bring these three things together gently,
you want to fold it really, really gently.
You don't want to knock out any of the
air that you've worked really really
hard on getting in there so these will
come together in one big bowl and then
we tip it into our saucepan which has
been lined with some butter and then
just dusted with some cornflour. Onto a
really, really low heat so I've got this
set at the second lowest temperature I
can possibly get and we're using
bessemer cookware which creates an
oven, you've got a little dome at the top
and this brings in another completely
different field of science which is
physics and we learn about how heat
moves, so as we add energy to the bottom
of our pan, we excite the particles, they
bump into each other and they move heat
all the way up the outside of the pot to
the top of the pot
and then heat starts to circulate like
it would in a normal oven. So we get an
oven atmosphere inside the pot and bessemer
is built specifically for that, they've
got this nice rounded dome on top, they've
got the little collar which lets the
steam out so you can create the oven, so
it's perfect for baking you when you
don't have an oven with you. Once it's
done I'm going to turn it out and allow
it to cool for again half an hour, 45
minutes, and I'm going to dress it with a
little bit of icing sugar, some cream and
some strawberries just like the Victoria sponge
Science is important because it helps us understand the world around us.
I've teamed up with the University of
Queensland, the place where I discovered
my love for science. To help you understand and
engage with the scientific world in a
fun and entertaining way through cooking, my
other love. To find out more about Food Lab and the
exclusive content, check out the online
series we've made. Take this egg. If I were
to drop it. And learn how science is happening
all around you.
Our sponge is done, it's been put aside to cool down, this is
going to blow your mind. I'm going to make
a pizza outdoors in a deep pan, deep pan
pizza, with no oven. So again we're using
the lid to create that
oven inside. So I'll take my pan down, put
here, everything gets mixed in it and as
I said you're going to think this is
magic but it's not. You know, it's the
magic of television, but this is done
live. Flour, one and a half cups of
self-raising flour, now it's important to
get self-raising flour. Every cup of
self-raising flour has about a teaspoon
of baking powder already mixed in it, so
once we add moisture to that it's going
to start to do what the sponge did, we
get a reaction, start to form bubbles,
and you're going to get a nice deep pan pizza. Flour in,
give that a mix. One nice pinch of salt in
there with my flour. Some warm water and
a cup of warm water. Hopefully I'll leave
some of it back just in case I need to
add some more and about a tablespoon of
oil. Normally a pizza dough has yeast in
it, you have to let it sit for that yeast
to activate and start to bubble. The
baking powder sort of does the
fermentation or creates the reaction that
the yeast would. So mix all this together,
it's going to form a claggy dough and
it's going to look like you're just
making a mess but you're not. And the
first time I ever made this I thought to
myself, "this is just going to end up with
me cleaning up a really big mess", but it
doesn't. I just want to get to the point
where all of our flour and water is
mixed together. This is all due to the
technology that goes into bessemer,
so it's a really good non-stick surface,
so this cooks out and slides out really
easily and we can create that oven when
we put the lid back on it. So I just want
to spread this out to the edges like
so. If you don't want as deep a pan don't
add as much flour and water to mixture,
but I like a nice big deep pan pizza. Tomato
paste, put it on and then just spread that
tomato paste over the top of the dough
and then it's just your favorite pizza
fillings on top or pizza toppings on
top, whatever you like I've got a nice
little assortment of the things that I
like, so some mushrooms, first spread that
out, some green capsicum, onion, try and
have things cut reasonably thin because
it only takes 15 to 20 minutes to cook
this so stuff needs to be able to cook
quickly. Some olives.
A few oregano leaves. A little sprinkle of
smoked paprika, some chorizo, bacon and
finally our cheese, I'm using a shredded
mozzarella. Now for the magic. Onto our
induction, heat on, I want a nice medium
high heat to begin with for about 10
minutes. And we're going to let that medium high
heat start to get a lot of temperature
in the oven then i'll turn it down for
the last 10 minutes. Lid on. 10 minutes at
180 then turn it down to about 120 for
the last 10 minutes and then you're done.
I guarantee you're going to think it's
magic until you try it at home but
something as simple as baking a sponge
and a pizza uses two really complex areas
of science in chemistry and physics but in
the end all they'll just taste good. One thing
we're probably not aware of is all our
grandmas were actually physicists and
chemists. On the next episode of Food Lab
we're going to take our first look at
pure food science and how innovation plays
a huge role in the food we eat today.
With molecular gastronomy. This is my
white chocolate popping candy and
raspberry gravel. Oh my goodness, that's the thing!
For recipes and extra Food Lab
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channels and website.
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