Welcome to HowToCookThat, today we’re going
to make this amazingly smooth strawberry icecream with fresh strawberries in it and dippin’
dots over the top using liquid nitrogen. And to help us with that we’re going to meet a
scientist Kiri from N2 in Sydney and we’re going to smash stuff too.
I’m Ann Reardon and this is The Sweetest Thing. When I was studying Nutrition and Food Science
at University, we use to do these labs that just went for hours. They were food science
labs and we’d all these different experiments. And I remember one of them we did literally
hours of testing egg whites to see which ones were more stable and which ones whipped better,
whether they were fresher ones or older ones and we just filled out tables of data on them.
And I remember thinking when am I ever going to need this level of detail when I’m working
as a dietitian. And it was true for the next few years when I had patients that I was working
with who had had open heart surgery or had been diagnosed with diabetes or had part of
their stomach removed from cancer, how long an egg white stayed whipped for or how to
temper chocolate is pretty irrelevant to what they needed to know. But fast forward to today
and I do use everything that I learnt in those labs when I’m developing recipes. And the
crazy thing is I have a couple of million followers on YouTube that are following all
the recipes that I’m making and asking technical questions every single week in the comments
about different ingredients and I wouldn’t be able to answer them if I hadn’t done all
those labs. And I love it when that happens. I couldn’t have planned or even imagined that
I’d be here today doing this. But everything just seems to work together and have a purpose.
Kiri from N2 is actually a chemical engineer, but like me he’s now using his science degree
to make people smile by making crazy desserts. These look delicious, nice fresh strawberries
and you’ve got big tanks of liquid nitrogen, what are we going to make today?
I’m going to make a strawberry and cream gelato. I love those little dippin’ dots that you’ve
got on top there, what ingredients do we need for this part.
I’ve got some nice fresh milk here, pouring cream, sugar, there’s some skim milk powder
here, this is a thickener that we use but you can xantham at home, some vanilla extract
and these are some nice fresh strawberries. I’ll put all of the recipe quantities on the
howtocookthat.net website in grams, ounces and cups and I’ll add a link to that below.
So we’re going to mix these all in together in the saucepan. Then I’ll get the cream and
pour it in. How many icecreams do you make in a day for
the store, how many would you sell in a day? On a weekday, probably about 500 and on weekends
we go up to about 1000 though. So you don’t do these for each icecream though?
No So how do you make these here in store?
We have a big pasteurizer it basically can cook up to 180 litres at a time. We put all
ingredients in just like we’re doing here but it’s much bigger and heats up, cools down
and then we just extract it into bottles. Right so it’s doing this exact process just
on a mass scale, you wouldn’t want to stir a pot for 1000 icecreams. Do you want the
vanilla in now. Yes put it in now.
And we’ll just whisk that up and you’re just looking for when it starts to bubble.
When it starts to bubble, it starts to get to boiling. You want to make sure it doesn’t
catch on the bottom, so whisking is good. Do you want these strawberries finely chopped?
Just as finely as you can do. When they’re in the gelato it will be nicely spread out
throughout the mixture and so each bite you have will have a bit of strawberry in it.
You’re just putting them in fresh. Yes because the way we freeze the icecream,
it’s so fresh so you can just put whatever you want in. It’s starting to boil now.
So we’re pouring it in. Start it mixing.
You have so many flavours up on your board, I can see vegan deconstructed chocolate lava,
salt-and-pepper calamari. These are crazy flavours, who comes up with all of these?
We have a bit of a creative team, between me the shop in Melbourne we all work together
and we come up with the flavours every week and plan them out.
Now to turn them into icecream you use these big tanks of liquid nitrogen and pour in a
little bit at a time. Just turn it off, scrape down the sides.
We’ll just add a bit more nitrogen and then once it’s a bit harder we’re going to add
the strawberries and then we’re going to let it harden up again so we can scoop it.
So what’s happening on a molecular level here, if we were to look at it under a microscope,
this icecream compared to if I make it at home in my icecream machine?
So what’s happening is the water in the mixture is freezing a lot faster, making smaller ice
crystals. The smaller the particles the smoother it
is on your tongue. Yes exactly.
If you can put the strawberries in now it’s got a bit of texture there. Now it’s in we’re
going to add some more nitrogen and let it harden up a bit.
And as you can see now that it’s getting harder the strawberry chunks are starting to break
up. It’s a big change from being a chemical engineer
to being a mad scientist flavour-creator for N2, how did you find that came about.
I did engineering, my boss Minh he was an solvency accountant so he would be sending
people bankrupt every day and we decided we wanted to do a job where we make people smile
every day rather than you know make spreadsheets or send people bankrupt.
I think icecream would make people smile all day.
It was a pretty nice change. It’s looking good.
So nice a flat. Yum
So we are going to use some whipped cream, give it a good shake.
Look at that. Okay so we’ve just got some freeze dried cherries
here. Can I have a look.
They’re nice and crunchy so I’m just going to sprinkle a little on top.
And they’re quite bitter so they’ll contrast a bit with the sweetness.
Yes exactly and just got a nice look to it. Now I was thinking today we could do dippin’
dots. That sounds like great fun.
So what have we got in here, what’s this green stuff?
This is a matcha gelato, matcha is like a Japanese green tea so we’re going to fill
up these syringes and dip it into nitrogen. These are just going to freeze instantly when
they hit the cold that’s the idea? Yeah so hopefully we’ll get some nice little
spheres of matcha gelato. Have you done this before?
No I haven’t actually. Ha you’re a true mad scientist doing experiments.
You know we’ve got a motto here, will it work? There’s only one way to find out. You have
to try it. How do we get them out?
Whoa. Look at that, okay shall we sprinkle them on top.
They taste good too. Very good. And there it’s ready.
Yum, can we eat it? Hmm that is so super smooth, that is really
good. Now if we don’t have liquid nitrogen at home
I guess we could just put it in an icecream machine just use the same recipe.
Yes you can do that, you can also use dry ice as well. Just crush it up in a bag, put
it in and an icecream machine works as well. My kids tried to make a thickshake with dry
ice and it shot the lid off. Oh no.
And went everywhere, so don’t put it in a blender.
Do you reckon we can do some experiments with the liquid nitrogen, do you know any cool
stuff we can do with it? Look we can try and smash some fruit if you
like. Awesome let’s smash some stuff.
Thankyou so much for having me today Kiri and for teaching me the secret behind your
N2 icecream and for being a good sport and doing dippin’ dots and smashing stuff.
You’re so welcome thanks for coming. Subscribe to HowToCookThat for more cakes,
chocolates and desserts. Click here for the recipe, here for my YouTube channel and here
for more of The Sweetest Thing. Make it a great week and I’ll see you all