I am not suggesting mechanical enthusiasts should use sugar as antifreeze in their engines!
Just kidding! What I mean is that many of us use sugar daily in numerous preparations but have no idea of its importance in the balancing of products that are commonly served at negative temperatures.
The amount of sugar we use in semifreddi, iced mousse cakes and ice-cream recipes does not only make our products more or less sweet, but it is an essential parameter of the dessert structure.
Sugar (or, better said, sugars) is the element that prevents water from freezing:
to put it simply, a higher content of sugar prevents freezing.
If we try and put in a freezer a thick syrup with a high sugar concentration we notice it remains liquid even at temperatures below zero, because ice crystals cannot form.
The most used sugar is sucrose, a.k.a. table sugar, that is also called granulated sugar.
All recipes simply call for “sugar”, except those that require a combination of glucosides (sugars).
Creams and fillings
These recipes call for “sucrose” to avoid confusion with other sugars such as glucose, dextrose, fructose, honey, isomalt, etc.
All sugars have a sweetening power as well as an anti-freezing power.
Sucrose is taken as a standard of 1 to establish the sweetening power; as we can see, sweetness varies among them all:
Dextrose 42 DE 0.7
Invert Sugar 1.2
Aspartame 200 times sweeter than sucrose
Stevia 300 times sweeter than sucrose
Sucralose 650 times sweeter than sucrose
Table sugar – or sucrose – is taken as a standard of 1 for antifreezing power, too:
Invert sugar 1.9
The concept I’d like you to understand here is that respecting balance in frozen desserts and ice cream is really crucial.
With ice creams and semifreddi we cannot rely on approximate amounts, because adding or removing 5 or 10 g can totally affect the success of our dessert.
At the same time we must check the dessert structure at negative temperatures:
if our ice cream is too soft, tends to collapse and looks very shiny the balancing mistake is an excessive amount of sugars.
Conversely, if the ice cream is too hard, almost rocky and impossible to scoop, this can be caused by low sugar content.
The problem, though, is that adding too much sugar to our dessert can make it nauseating:
for this reason sugars like dextrose are used, since they have an anti-freezing power similar to sucrose but a lower sweetening power.
Remember that pastry making is an exact science where there is no room for carelessness!
Have a nice dessert!