Air in ice cream
Air is an essential ingredient for ice creams and more particularly for milk-based ice creams. Without air, our ice creams would look more like ice cubes and would not have this creamy consistency. In pastry world, incorporating air into a preparation is called overrun. But how to incoporate it, how much air should be added ? Ice Ice Daddy .com tells you more about overrun.
A well balanced recipe
A recipe not balanced will limit the incorporation of air. It is therefore essential to have the best recipe. For example, dextrose is very useful but will tend to limit the overrun.
When ?
The overrun will be mainly done during the creaming phase in your ice-cream maker.
How much ?
It is possible to incororate more or less air in your preparation. And so much air can be incorporated that it has been necessary to impose some limits to manufacturers. The more air the ice cream contains, the smaller the weight is. For French regulation, one liter of ice cream must weight more than 450g (and sometimes more depending on the recipe). For American regulation, one liter of ice cream must weight more than 490g (4.5 pounds to the gallon).
As air is a free ingredient, you now understand that cheaper products will tend to contain more air. But no easy to check it because to compare two products, the compositions must be identical. Let us make a small demonstration with two ice creams sold in France.
| Vanilla ice cream | |
|---|---|
| Low cost trade mark | 1000 ml - 500 g so 500g/liter |
| National trade mark | 900 ml - 472 g so 524g/liter |
To have a high quality ice cream, the practice in artisanal ice cream is to obtain a 35% overrun rate. American ice creams made by Haagen Dasz are known to have an overrun rate about 25%.
Advantages and disadvantages ?
With a low overrun rate, the ice cream will be heavy. With an high overrun rate, it will have no taste and no consistencyin mouth.
Is there an advantage for an ice cream with an high overrun ? If the taste will be more or less lost, it will also reduce the calorie intake. Let's take again the example of vanilla ice cream.
| For 100 g of | Energy |
|---|---|
| Low price vanilla ice cream 8% fat | 190 kcal |
| Standard vanilla ice cream 8% fat | 184 kcal |
| Super premium vanilla american ice cream 17% fat | 251 kcal |
When eating ice cream, the portion consumed must be evaluated by volume and not by weight. We eat two scoops of ice cream and not 100 g of ice cream.
| For 2 scoops (100 ml) of | Weight of ice cream | Calorie intake |
|---|---|---|
| Low price vanilla ice cream 8% fat | 50 g | 95 kcal |
| Standard vanilla ice cream 8% fat | 52,4 g | 96 kcal |
| Super premium vanilla american ice cream 17% fat | 86 g | 215 kcal |
Let us forget the case of american ice cream, very rich and heavy because with a low overrun. Low price vanilla ice cream is in theory more caloric than standard vanilla ice cream. But as overrun is higher, at an equivalent portion (2 scoops), we will actually eat less ice cream and more air so the calorie intake of these two products will be the same.
Controlling the overrun
In professional environment, the use of a continuous freezer will allow to control overrun rate very precisely because the quantity of injected air will be measured. An ice-cream machine will allow less precision because the incorporated air is the ambient air.
At home with an ice-cream maker, it will be difficult to control this overrun rate.
We can therefore get an idea thanks to the capacity of the ice cream maker. Another possibility would be to pause the creaming phase, measure the overrun rate to check if we must stop or continue the process. Ice Ice Daddy .com will tell you soon more about this subject.