Why is ice cream not rock hard?

Most of us will have tried to make our own ice cream when we were kids. And most of us will have been disappointed by the result. It’s not that easy to make good ice cream. But there are a few secrets to getting it right.

When you take a steak out of the freezer, it’s usually frozen solid. Ice cream isn’t. Why is that? It’s obvious, isn’t it? Ice cream is more than just frozen water, and it’s also been churned. Or something like that, right? Right! But there’s more to it than that. The main ingredients of ice cream are cream and sugar – and not only because that’s a delicious combination. Let’s talk about salt for a moment.

In winter, when you want to make sure your driveway doesn’t get icy, you use salt. This is because salt reduces the temperature at which water freezes. So instead of your driveway getting icy at zero degrees centigrade, it will stay ice-free for much longer. 

Sugar is like salt 

The same principle is at work in ice cream, but we use sugar instead of salt because it’s much tastier. As the ice cream mixture is cooled down, some of the water freezes and forms ice crystals. The concentration of sugar increases in the rest of the water, lowering the freezing point of the sugar-water solution – just like the salt in the example above. As a result, the ice cream stays soft. 

But that’s not all there is to it. The way the ice cream is frozen matters too. We do this in horizontal cylinders which are cooled from the outside. During the freezing process, the ice crystals are scraped from the cylinder walls. This stops the ice crystals from growing too big and giving the ice cream a sand-like texture. We can also whip in extra air, which makes the ice cream even lighter and creamier. 

By the way, Ice cream produced by Emmi keeps for quite a long time if stored at –18°C. However, most freezer compartments in fridges cannot maintain such a low temperature. This causes ice crystals to grow, which you can not only feel with your tongue when eating the ice cream, but also see on the surface of the ice cream.  

Pierrot is back 

Many will remember the colourful harlequin from the 1980s. The iconic ice lollies are making a comeback: made according the original recipe and in the same design, the four varieties Tom, Pierino, Magic and Croquant are now available again: www.pierrot-glace.ch 

Questions on nutrition?

We are happy to advise you on nutritional matters relating to Emmi products on Thursdays between 1 p.m. and 3 p.m.

+41 58 227 52 55