Technical Note #007: Why is serving temperature so important?

PAC (Antifreezing Power) is probably one of the best-known indicators when it comes to balancing an ice cream recipe.

It helps assess, in particular, the influence of sugars on the freezing of the aqueous phase.

But PAC remains a formulation indicator.

For the professional, the final question is different:

What will happen to my ice cream at the temperature at which I will actually serve it?

This is where serving temperature and the freezing curve become particularly important.

From PAC to the actual behaviour of ice cream

PAC characterizes the overall antifreeze effect of the sugars present in a recipe.

But ice cream cannot be defined simply by a PAC value.

At a given temperature, part of the water is frozen while another part remains liquid. As the temperature changes, this proportion continuously changes.

Knowing the PAC of a recipe is therefore not enough to accurately describe its behaviour at a given serving temperature.

PAC is therefore a way of calculating the behaviour of the aqueous phase, not a complete description of that behaviour.

The essential question: how much water is frozen?

Consider an ice cream intended to be served at −12.5 °C.

At this temperature, not all of the water in the recipe is obviously in the form of ice.

Some of it remains unfrozen, influenced in particular by the dissolved solids, especially sugars.

The proportion of frozen water directly affects:

• hardness;

• softness;

• ease of serving;

• perceived texture.

And this is where Gelato Pro Software goes further

In Gelato Pro Software, PAC is not displayed as an indicator in the formulation results.

The PAC values associated with individual sugars are entered in the ingredient management section. They are then used in the model calculations, together with the other formulation data, to determine the physical behaviour of the ice cream.

The model provides data that are directly useful to the professional:

• serving temperature;

• freezing curve;

• percentage of frozen water;

• viscosity of the unfrozen phase;

• hardness curve.

  
  

These data help assess not only the hardness of the ice cream at its serving temperature, but also the viscosity of its unfrozen phase, a parameter that contributes to its behaviour and texture.

In other words:

PAC is part of the calculation. The result the professional is looking for is the behaviour of the ice cream.

This is an important distinction.

The professional does not necessarily need to know only that a recipe has a particular PAC value.

What matters is understanding how that recipe will behave when it is actually served.

From formulation to physics

This is the philosophy behind Gelato Pro Software: formulation is not an end in itself.

Formulation calculations allow us to go further and translate the composition of a recipe into physical behaviour.

Instead of asking: “What is my PAC?”

we can go as far as: “At my serving temperature, what proportion of the water is frozen, and how will my ice cream behave?”

This transition from formulation calculations to the actual physics of ice cream is what makes the Gelato Pro Software thermal model valuable.

Gelato Pro Software

Gelato Pro Software uses formulation data to analyse the thermal behaviour of your recipes and visualise their freezing curve, serving temperature, hardness profile and the viscosity of the unfrozen phase.